From 95ca90726ea6c9444c752ea370e35ec7b6776434 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Wed, 16 Dec 2020 12:55:27 +0100 Subject: selinux: handle MPTCP consistently with TCP The MPTCP protocol uses a specific protocol value, even if it's an extension to TCP. Additionally, MPTCP sockets could 'fall-back' to TCP at run-time, depending on peer MPTCP support and available resources. As a consequence of the specific protocol number, selinux applies the raw_socket class to MPTCP sockets. Existing TCP application converted to MPTCP - or forced to use MPTCP socket with user-space hacks - will need an updated policy to run successfully. This change lets selinux attach the TCP socket class to MPTCP sockets, too, so that no policy changes are needed in the above scenario. Note that the MPTCP is setting, propagating and updating the security context on all the subflows and related request socket. Link: https://lore.kernel.org/linux-security-module/CAHC9VhTaK3xx0hEGByD2zxfF7fadyPP1kb-WeWH_YCyq9X-sRg@mail.gmail.com/T/#t Signed-off-by: Paolo Abeni [PM: tweaked subject's prefix] Signed-off-by: Paul Moore --- security/selinux/hooks.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 644b17ec9e63..75e7568cf607 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1120,7 +1120,8 @@ static inline u16 inode_mode_to_security_class(umode_t mode) static inline int default_protocol_stream(int protocol) { - return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); + return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || + protocol == IPPROTO_MPTCP); } static inline int default_protocol_dgram(int protocol) -- cgit From a9ffe682c58aaff643764547f5420e978b6e0830 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Sat, 19 Dec 2020 12:05:27 +0200 Subject: selinux: fix inconsistency between inode_getxattr and inode_listsecurity When inode has no listxattr op of its own (e.g. squashfs) vfs_listxattr calls the LSM inode_listsecurity hooks to list the xattrs that LSMs will intercept in inode_getxattr hooks. When selinux LSM is installed but not initialized, it will list the security.selinux xattr in inode_listsecurity, but will not intercept it in inode_getxattr. This results in -ENODATA for a getxattr call for an xattr returned by listxattr. This situation was manifested as overlayfs failure to copy up lower files from squashfs when selinux is built-in but not initialized, because ovl_copy_xattr() iterates the lower inode xattrs by vfs_listxattr() and vfs_getxattr(). Match the logic of inode_listsecurity to that of inode_getxattr and do not list the security.selinux xattr if selinux is not initialized. Reported-by: Michael Labriola Tested-by: Michael Labriola Link: https://lore.kernel.org/linux-unionfs/2nv9d47zt7.fsf@aldarion.sourceruckus.org/ Fixes: c8e222616c7e ("selinux: allow reading labels before policy is loaded") Cc: stable@vger.kernel.org#v5.9+ Signed-off-by: Amir Goldstein Reviewed-by: Ondrej Mosnacek Signed-off-by: Paul Moore --- security/selinux/hooks.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 75e7568cf607..7fb7ff03eaa9 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3414,6 +3414,10 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name, static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) { const int len = sizeof(XATTR_NAME_SELINUX); + + if (!selinux_initialized(&selinux_state)) + return 0; + if (buffer && len <= buffer_size) memcpy(buffer, XATTR_NAME_SELINUX, len); return len; -- cgit From 08abe46b2cfcf5f815cd4961b1bf9e10b1714c6d Mon Sep 17 00:00:00 2001 From: Ondrej Mosnacek Date: Wed, 13 Jan 2021 13:38:02 +0100 Subject: selinux: fall back to SECURITY_FS_USE_GENFS if no xattr support When a superblock is assigned the SECURITY_FS_USE_XATTR behavior by the policy yet it lacks xattr support, try to fall back to genfs rather than rejecting the mount. If a genfscon rule is found for the filesystem, then change the behavior to SECURITY_FS_USE_GENFS, otherwise reject the mount as before. A similar fallback is already done in security_fs_use() if no behavior specification is found for the given filesystem. This is needed e.g. for virtiofs, which may or may not support xattrs depending on the backing host filesystem. Example: # seinfo --genfs | grep ' ramfs' genfscon ramfs / system_u:object_r:ramfs_t:s0 # echo '(fsuse xattr ramfs (system_u object_r fs_t ((s0) (s0))))' >ramfs_xattr.cil # semodule -i ramfs_xattr.cil # mount -t ramfs none /mnt Before: mount: /mnt: mount(2) system call failed: Operation not supported. After: (mount succeeds) # ls -Zd /mnt system_u:object_r:ramfs_t:s0 /mnt See also: https://lore.kernel.org/selinux/20210105142148.GA3200@redhat.com/T/ https://github.com/fedora-selinux/selinux-policy/pull/478 Cc: Vivek Goyal Signed-off-by: Ondrej Mosnacek Signed-off-by: Paul Moore --- security/selinux/hooks.c | 77 ++++++++++++++++++++++++++++++++---------------- 1 file changed, 52 insertions(+), 25 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 7fb7ff03eaa9..f2b272c9eaf3 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -484,6 +484,55 @@ static int selinux_is_sblabel_mnt(struct super_block *sb) } } +static int sb_check_xattr_support(struct super_block *sb) +{ + struct superblock_security_struct *sbsec = sb->s_security; + struct dentry *root = sb->s_root; + struct inode *root_inode = d_backing_inode(root); + u32 sid; + int rc; + + /* + * Make sure that the xattr handler exists and that no + * error other than -ENODATA is returned by getxattr on + * the root directory. -ENODATA is ok, as this may be + * the first boot of the SELinux kernel before we have + * assigned xattr values to the filesystem. + */ + if (!(root_inode->i_opflags & IOP_XATTR)) { + pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", + sb->s_id, sb->s_type->name); + goto fallback; + } + + rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); + if (rc < 0 && rc != -ENODATA) { + if (rc == -EOPNOTSUPP) { + pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", + sb->s_id, sb->s_type->name); + goto fallback; + } else { + pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", + sb->s_id, sb->s_type->name, -rc); + return rc; + } + } + return 0; + +fallback: + /* No xattr support - try to fallback to genfs if possible. */ + rc = security_genfs_sid(&selinux_state, sb->s_type->name, "/", + SECCLASS_DIR, &sid); + if (rc) + return -EOPNOTSUPP; + + pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", + sb->s_id, sb->s_type->name); + sbsec->behavior = SECURITY_FS_USE_GENFS; + sbsec->sid = sid; + return 0; +} + static int sb_finish_set_opts(struct super_block *sb) { struct superblock_security_struct *sbsec = sb->s_security; @@ -492,30 +541,9 @@ static int sb_finish_set_opts(struct super_block *sb) int rc = 0; if (sbsec->behavior == SECURITY_FS_USE_XATTR) { - /* Make sure that the xattr handler exists and that no - error other than -ENODATA is returned by getxattr on - the root directory. -ENODATA is ok, as this may be - the first boot of the SELinux kernel before we have - assigned xattr values to the filesystem. */ - if (!(root_inode->i_opflags & IOP_XATTR)) { - pr_warn("SELinux: (dev %s, type %s) has no " - "xattr support\n", sb->s_id, sb->s_type->name); - rc = -EOPNOTSUPP; - goto out; - } - - rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); - if (rc < 0 && rc != -ENODATA) { - if (rc == -EOPNOTSUPP) - pr_warn("SELinux: (dev %s, type " - "%s) has no security xattr handler\n", - sb->s_id, sb->s_type->name); - else - pr_warn("SELinux: (dev %s, type " - "%s) getxattr errno %d\n", sb->s_id, - sb->s_type->name, -rc); - goto out; - } + rc = sb_check_xattr_support(sb); + if (rc) + return rc; } sbsec->flags |= SE_SBINITIALIZED; @@ -554,7 +582,6 @@ static int sb_finish_set_opts(struct super_block *sb) spin_lock(&sbsec->isec_lock); } spin_unlock(&sbsec->isec_lock); -out: return rc; } -- cgit From 29cd6591ab6fee3125ea5c1bf350f5013bc615e1 Mon Sep 17 00:00:00 2001 From: Daniel Colascione Date: Fri, 8 Jan 2021 14:22:22 -0800 Subject: selinux: teach SELinux about anonymous inodes This change uses the anon_inodes and LSM infrastructure introduced in the previous patches to give SELinux the ability to control anonymous-inode files that are created using the new anon_inode_getfd_secure() function. A SELinux policy author detects and controls these anonymous inodes by adding a name-based type_transition rule that assigns a new security type to anonymous-inode files created in some domain. The name used for the name-based transition is the name associated with the anonymous inode for file listings --- e.g., "[userfaultfd]" or "[perf_event]". Example: type uffd_t; type_transition sysadm_t sysadm_t : anon_inode uffd_t "[userfaultfd]"; allow sysadm_t uffd_t:anon_inode { create }; (The next patch in this series is necessary for making userfaultfd support this new interface. The example above is just for exposition.) Signed-off-by: Daniel Colascione Signed-off-by: Lokesh Gidra Signed-off-by: Paul Moore --- security/selinux/hooks.c | 57 +++++++++++++++++++++++++++++++++++++ security/selinux/include/classmap.h | 2 ++ 2 files changed, 59 insertions(+) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index f2b272c9eaf3..af2994adf9dd 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2962,6 +2962,62 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir, return 0; } +static int selinux_inode_init_security_anon(struct inode *inode, + const struct qstr *name, + const struct inode *context_inode) +{ + const struct task_security_struct *tsec = selinux_cred(current_cred()); + struct common_audit_data ad; + struct inode_security_struct *isec; + int rc; + + if (unlikely(!selinux_initialized(&selinux_state))) + return 0; + + isec = selinux_inode(inode); + + /* + * We only get here once per ephemeral inode. The inode has + * been initialized via inode_alloc_security but is otherwise + * untouched. + */ + + if (context_inode) { + struct inode_security_struct *context_isec = + selinux_inode(context_inode); + if (context_isec->initialized != LABEL_INITIALIZED) { + pr_err("SELinux: context_inode is not initialized"); + return -EACCES; + } + + isec->sclass = context_isec->sclass; + isec->sid = context_isec->sid; + } else { + isec->sclass = SECCLASS_ANON_INODE; + rc = security_transition_sid( + &selinux_state, tsec->sid, tsec->sid, + isec->sclass, name, &isec->sid); + if (rc) + return rc; + } + + isec->initialized = LABEL_INITIALIZED; + /* + * Now that we've initialized security, check whether we're + * allowed to actually create this type of anonymous inode. + */ + + ad.type = LSM_AUDIT_DATA_INODE; + ad.u.inode = inode; + + return avc_has_perm(&selinux_state, + tsec->sid, + isec->sid, + isec->sclass, + FILE__CREATE, + &ad); +} + static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) { return may_create(dir, dentry, SECCLASS_FILE); @@ -7032,6 +7088,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), + LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), LSM_HOOK_INIT(inode_create, selinux_inode_create), LSM_HOOK_INIT(inode_link, selinux_inode_link), LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h index 40cebde62856..ba2e01a6955c 100644 --- a/security/selinux/include/classmap.h +++ b/security/selinux/include/classmap.h @@ -249,6 +249,8 @@ struct security_class_mapping secclass_map[] = { {"open", "cpu", "kernel", "tracepoint", "read", "write"} }, { "lockdown", { "integrity", "confidentiality", NULL } }, + { "anon_inode", + { COMMON_FILE_PERMS, NULL } }, { NULL } }; -- cgit From 21cb47be6fb9ece7e6ee63f6780986faa384a77c Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 21 Jan 2021 14:19:25 +0100 Subject: inode: make init and permission helpers idmapped mount aware The inode_owner_or_capable() helper determines whether the caller is the owner of the inode or is capable with respect to that inode. Allow it to handle idmapped mounts. If the inode is accessed through an idmapped mount it according to the mount's user namespace. Afterwards the checks are identical to non-idmapped mounts. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Similarly, allow the inode_init_owner() helper to handle idmapped mounts. It initializes a new inode on idmapped mounts by mapping the fsuid and fsgid of the caller from the mount's user namespace. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-7-christian.brauner@ubuntu.com Cc: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig Reviewed-by: James Morris Signed-off-by: Christian Brauner --- fs/9p/acl.c | 2 +- fs/9p/vfs_inode.c | 2 +- fs/attr.c | 6 +++--- fs/bfs/dir.c | 2 +- fs/btrfs/inode.c | 2 +- fs/btrfs/ioctl.c | 10 +++++----- fs/btrfs/tests/btrfs-tests.c | 2 +- fs/crypto/policy.c | 2 +- fs/efivarfs/file.c | 2 +- fs/ext2/ialloc.c | 2 +- fs/ext2/ioctl.c | 6 +++--- fs/ext4/ialloc.c | 2 +- fs/ext4/ioctl.c | 15 ++++++++------- fs/f2fs/file.c | 14 +++++++------- fs/f2fs/namei.c | 2 +- fs/f2fs/xattr.c | 2 +- fs/fcntl.c | 2 +- fs/gfs2/file.c | 2 +- fs/hfsplus/inode.c | 2 +- fs/hfsplus/ioctl.c | 2 +- fs/hugetlbfs/inode.c | 2 +- fs/inode.c | 36 ++++++++++++++++++++++++++---------- fs/jfs/ioctl.c | 2 +- fs/jfs/jfs_inode.c | 2 +- fs/minix/bitmap.c | 2 +- fs/namei.c | 5 +++-- fs/nilfs2/inode.c | 2 +- fs/nilfs2/ioctl.c | 2 +- fs/ocfs2/dlmfs/dlmfs.c | 4 ++-- fs/ocfs2/ioctl.c | 2 +- fs/ocfs2/namei.c | 2 +- fs/omfs/inode.c | 2 +- fs/overlayfs/dir.c | 2 +- fs/overlayfs/file.c | 4 ++-- fs/overlayfs/super.c | 2 +- fs/overlayfs/util.c | 2 +- fs/posix_acl.c | 2 +- fs/ramfs/inode.c | 2 +- fs/reiserfs/ioctl.c | 4 ++-- fs/reiserfs/namei.c | 2 +- fs/sysv/ialloc.c | 2 +- fs/ubifs/dir.c | 2 +- fs/ubifs/ioctl.c | 2 +- fs/udf/ialloc.c | 2 +- fs/ufs/ialloc.c | 2 +- fs/xattr.c | 3 ++- fs/xfs/xfs_ioctl.c | 2 +- fs/zonefs/super.c | 2 +- include/linux/fs.h | 8 ++++---- kernel/bpf/inode.c | 2 +- mm/madvise.c | 3 ++- mm/mincore.c | 3 ++- mm/shmem.c | 2 +- security/selinux/hooks.c | 4 ++-- 54 files changed, 112 insertions(+), 91 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/fs/9p/acl.c b/fs/9p/acl.c index 6261719f6f2a..d77b28e8d57a 100644 --- a/fs/9p/acl.c +++ b/fs/9p/acl.c @@ -258,7 +258,7 @@ static int v9fs_xattr_set_acl(const struct xattr_handler *handler, if (S_ISLNK(inode->i_mode)) return -EOPNOTSUPP; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; if (value) { /* update the cached acl value */ diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 4a937fac1acb..f66eb3c12c8a 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -251,7 +251,7 @@ int v9fs_init_inode(struct v9fs_session_info *v9ses, { int err = 0; - inode_init_owner(inode, NULL, mode); + inode_init_owner(&init_user_ns,inode, NULL, mode); inode->i_blocks = 0; inode->i_rdev = rdev; inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); diff --git a/fs/attr.c b/fs/attr.c index c9e29e589cec..00ae0b000146 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -87,7 +87,7 @@ int setattr_prepare(struct dentry *dentry, struct iattr *attr) /* Make sure a caller can chmod. */ if (ia_valid & ATTR_MODE) { - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; /* Also check the setgid bit! */ if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid : @@ -98,7 +98,7 @@ int setattr_prepare(struct dentry *dentry, struct iattr *attr) /* Check for setting the inode time. */ if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) { - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; } @@ -243,7 +243,7 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de if (IS_IMMUTABLE(inode)) return -EPERM; - if (!inode_owner_or_capable(inode)) { + if (!inode_owner_or_capable(&init_user_ns, inode)) { error = inode_permission(&init_user_ns, inode, MAY_WRITE); if (error) diff --git a/fs/bfs/dir.c b/fs/bfs/dir.c index d8dfe3a0cb39..be1335a8d25b 100644 --- a/fs/bfs/dir.c +++ b/fs/bfs/dir.c @@ -96,7 +96,7 @@ static int bfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, } set_bit(ino, info->si_imap); info->si_freei--; - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); inode->i_blocks = 0; inode->i_op = &bfs_file_inops; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 512ee2650bbb..07fe8b2f3bab 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -6190,7 +6190,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, if (ret != 0) goto fail_unlock; - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode_set_bytes(inode, 0); inode->i_mtime = current_time(inode); diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 8ced6dfefee4..1f763c60415b 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -213,7 +213,7 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg) const char *comp = NULL; u32 binode_flags; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; if (btrfs_root_readonly(root)) @@ -429,7 +429,7 @@ static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg) unsigned old_i_flags; int ret = 0; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; if (btrfs_root_readonly(root)) @@ -1862,7 +1862,7 @@ static noinline int __btrfs_ioctl_snap_create(struct file *file, btrfs_info(BTRFS_I(file_inode(file))->root->fs_info, "Snapshot src from another FS"); ret = -EXDEV; - } else if (!inode_owner_or_capable(src_inode)) { + } else if (!inode_owner_or_capable(&init_user_ns, src_inode)) { /* * Subvolume creation is not restricted, but snapshots * are limited to own subvolumes only @@ -1982,7 +1982,7 @@ static noinline int btrfs_ioctl_subvol_setflags(struct file *file, u64 flags; int ret = 0; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; ret = mnt_want_write_file(file); @@ -4453,7 +4453,7 @@ static long _btrfs_ioctl_set_received_subvol(struct file *file, int ret = 0; int received_uuid_changed; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; ret = mnt_want_write_file(file); diff --git a/fs/btrfs/tests/btrfs-tests.c b/fs/btrfs/tests/btrfs-tests.c index 6bd97bd4cb37..3a4099a2bf05 100644 --- a/fs/btrfs/tests/btrfs-tests.c +++ b/fs/btrfs/tests/btrfs-tests.c @@ -62,7 +62,7 @@ struct inode *btrfs_new_test_inode(void) BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY; BTRFS_I(inode)->location.objectid = BTRFS_FIRST_FREE_OBJECTID; BTRFS_I(inode)->location.offset = 0; - inode_init_owner(inode, NULL, S_IFREG); + inode_init_owner(&init_user_ns, inode, NULL, S_IFREG); return inode; } diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c index a51cef6bd27f..ed3d623724cd 100644 --- a/fs/crypto/policy.c +++ b/fs/crypto/policy.c @@ -465,7 +465,7 @@ int fscrypt_ioctl_set_policy(struct file *filp, const void __user *arg) return -EFAULT; policy.version = version; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; ret = mnt_want_write_file(filp); diff --git a/fs/efivarfs/file.c b/fs/efivarfs/file.c index feaa5e182b7b..e6bc0302643b 100644 --- a/fs/efivarfs/file.c +++ b/fs/efivarfs/file.c @@ -137,7 +137,7 @@ efivarfs_ioc_setxflags(struct file *file, void __user *arg) unsigned int oldflags = efivarfs_getflags(inode); int error; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; if (copy_from_user(&flags, arg, sizeof(flags))) diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c index 432c3febea6d..df14e750e9fe 100644 --- a/fs/ext2/ialloc.c +++ b/fs/ext2/ialloc.c @@ -551,7 +551,7 @@ got: inode->i_uid = current_fsuid(); inode->i_gid = dir->i_gid; } else - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode->i_ino = ino; inode->i_blocks = 0; diff --git a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c index 32a8d10b579d..b399cbb7022d 100644 --- a/fs/ext2/ioctl.c +++ b/fs/ext2/ioctl.c @@ -39,7 +39,7 @@ long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) if (ret) return ret; - if (!inode_owner_or_capable(inode)) { + if (!inode_owner_or_capable(&init_user_ns, inode)) { ret = -EACCES; goto setflags_out; } @@ -84,7 +84,7 @@ setflags_out: case EXT2_IOC_SETVERSION: { __u32 generation; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; ret = mnt_want_write_file(filp); if (ret) @@ -117,7 +117,7 @@ setversion_out: if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode)) return -ENOTTY; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; if (get_user(rsv_window_size, (int __user *)arg)) diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index b215c564bc31..00c1ec6eee16 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -972,7 +972,7 @@ struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir, inode->i_uid = current_fsuid(); inode->i_gid = dir->i_gid; } else - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); if (ext4_has_feature_project(sb) && ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index d9665d2f82db..ab80e2493fdc 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -139,7 +139,8 @@ static long swap_inode_boot_loader(struct super_block *sb, } if (IS_RDONLY(inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) || - !inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN)) { + !inode_owner_or_capable(&init_user_ns, inode) || + !capable(CAP_SYS_ADMIN)) { err = -EPERM; goto journal_err_out; } @@ -829,7 +830,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) case FS_IOC_SETFLAGS: { int err; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; if (get_user(flags, (int __user *) arg)) @@ -871,7 +872,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) __u32 generation; int err; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; if (ext4_has_metadata_csum(inode->i_sb)) { @@ -1010,7 +1011,7 @@ mext_out: case EXT4_IOC_MIGRATE: { int err; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; err = mnt_want_write_file(filp); @@ -1032,7 +1033,7 @@ mext_out: case EXT4_IOC_ALLOC_DA_BLKS: { int err; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; err = mnt_want_write_file(filp); @@ -1217,7 +1218,7 @@ resizefs_out: case EXT4_IOC_CLEAR_ES_CACHE: { - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; ext4_clear_inode_es(inode); return 0; @@ -1263,7 +1264,7 @@ resizefs_out: return -EFAULT; /* Make sure caller has proper permission */ - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; if (fa.fsx_xflags & ~EXT4_SUPPORTED_FS_XFLAGS) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index f585545277d7..5fc0ff28b5dd 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1961,7 +1961,7 @@ static int f2fs_ioc_setflags(struct file *filp, unsigned long arg) u32 iflags; int ret; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; if (get_user(fsflags, (int __user *)arg)) @@ -2008,7 +2008,7 @@ static int f2fs_ioc_start_atomic_write(struct file *filp) struct f2fs_sb_info *sbi = F2FS_I_SB(inode); int ret; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; if (!S_ISREG(inode->i_mode)) @@ -2075,7 +2075,7 @@ static int f2fs_ioc_commit_atomic_write(struct file *filp) struct inode *inode = file_inode(filp); int ret; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; ret = mnt_want_write_file(filp); @@ -2117,7 +2117,7 @@ static int f2fs_ioc_start_volatile_write(struct file *filp) struct inode *inode = file_inode(filp); int ret; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; if (!S_ISREG(inode->i_mode)) @@ -2152,7 +2152,7 @@ static int f2fs_ioc_release_volatile_write(struct file *filp) struct inode *inode = file_inode(filp); int ret; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; ret = mnt_want_write_file(filp); @@ -2181,7 +2181,7 @@ static int f2fs_ioc_abort_volatile_write(struct file *filp) struct inode *inode = file_inode(filp); int ret; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; ret = mnt_want_write_file(filp); @@ -3158,7 +3158,7 @@ static int f2fs_ioc_fssetxattr(struct file *filp, unsigned long arg) return -EFAULT; /* Make sure caller has proper permission */ - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; if (fa.fsx_xflags & ~F2FS_SUPPORTED_XFLAGS) diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c index 6edb1ab579a1..ad98926bacac 100644 --- a/fs/f2fs/namei.c +++ b/fs/f2fs/namei.c @@ -46,7 +46,7 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode) nid_free = true; - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode->i_ino = ino; inode->i_blocks = 0; diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c index 65afcc3cc68a..d772bf13a814 100644 --- a/fs/f2fs/xattr.c +++ b/fs/f2fs/xattr.c @@ -114,7 +114,7 @@ static int f2fs_xattr_advise_set(const struct xattr_handler *handler, unsigned char old_advise = F2FS_I(inode)->i_advise; unsigned char new_advise; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; if (value == NULL) return -EINVAL; diff --git a/fs/fcntl.c b/fs/fcntl.c index 05b36b28f2e8..74d99731fd43 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -46,7 +46,7 @@ static int setfl(int fd, struct file * filp, unsigned long arg) /* O_NOATIME can only be set by the owner or superuser */ if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME)) - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; /* required for strict SunOS emulation */ diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index b39b339feddc..1d994bdfffaa 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -238,7 +238,7 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask, goto out; error = -EACCES; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) goto out; error = 0; diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c index e3da9e96b835..21357046b039 100644 --- a/fs/hfsplus/inode.c +++ b/fs/hfsplus/inode.c @@ -376,7 +376,7 @@ struct inode *hfsplus_new_inode(struct super_block *sb, struct inode *dir, return NULL; inode->i_ino = sbi->next_cnid++; - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); set_nlink(inode, 1); inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); diff --git a/fs/hfsplus/ioctl.c b/fs/hfsplus/ioctl.c index ce15b9496b77..3edb1926d127 100644 --- a/fs/hfsplus/ioctl.c +++ b/fs/hfsplus/ioctl.c @@ -91,7 +91,7 @@ static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags) if (err) goto out; - if (!inode_owner_or_capable(inode)) { + if (!inode_owner_or_capable(&init_user_ns, inode)) { err = -EACCES; goto out_drop_write; } diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index b5c109703daa..6737929e443c 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -836,7 +836,7 @@ static struct inode *hugetlbfs_get_inode(struct super_block *sb, struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode); inode->i_ino = get_next_ino(); - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); lockdep_set_class(&inode->i_mapping->i_mmap_rwsem, &hugetlbfs_i_mmap_rwsem_key); inode->i_mapping->a_ops = &hugetlbfs_aops; diff --git a/fs/inode.c b/fs/inode.c index cd40cbf87ce4..a9ac97a27784 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -2130,14 +2130,21 @@ EXPORT_SYMBOL(init_special_inode); /** * inode_init_owner - Init uid,gid,mode for new inode according to posix standards + * @mnt_userns: User namespace of the mount the inode was created from * @inode: New inode * @dir: Directory inode * @mode: mode of the new inode + * + * If the inode has been created through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then take + * care to map the inode according to @mnt_userns before checking permissions + * and initializing i_uid and i_gid. On non-idmapped mounts or if permission + * checking is to be performed on the raw inode simply passs init_user_ns. */ -void inode_init_owner(struct inode *inode, const struct inode *dir, - umode_t mode) +void inode_init_owner(struct user_namespace *mnt_userns, struct inode *inode, + const struct inode *dir, umode_t mode) { - inode->i_uid = current_fsuid(); + inode->i_uid = fsuid_into_mnt(mnt_userns); if (dir && dir->i_mode & S_ISGID) { inode->i_gid = dir->i_gid; @@ -2145,32 +2152,41 @@ void inode_init_owner(struct inode *inode, const struct inode *dir, if (S_ISDIR(mode)) mode |= S_ISGID; else if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP) && - !in_group_p(inode->i_gid) && - !capable_wrt_inode_uidgid(&init_user_ns, dir, - CAP_FSETID)) + !in_group_p(i_gid_into_mnt(mnt_userns, dir)) && + !capable_wrt_inode_uidgid(mnt_userns, dir, CAP_FSETID)) mode &= ~S_ISGID; } else - inode->i_gid = current_fsgid(); + inode->i_gid = fsgid_into_mnt(mnt_userns); inode->i_mode = mode; } EXPORT_SYMBOL(inode_init_owner); /** * inode_owner_or_capable - check current task permissions to inode + * @mnt_userns: user namespace of the mount the inode was found from * @inode: inode being checked * * Return true if current either has CAP_FOWNER in a namespace with the * inode owner uid mapped, or owns the file. + * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then take + * care to map the inode according to @mnt_userns before checking permissions. + * On non-idmapped mounts or if permission checking is to be performed on the + * raw inode simply passs init_user_ns. */ -bool inode_owner_or_capable(const struct inode *inode) +bool inode_owner_or_capable(struct user_namespace *mnt_userns, + const struct inode *inode) { + kuid_t i_uid; struct user_namespace *ns; - if (uid_eq(current_fsuid(), inode->i_uid)) + i_uid = i_uid_into_mnt(mnt_userns, inode); + if (uid_eq(current_fsuid(), i_uid)) return true; ns = current_user_ns(); - if (kuid_has_mapping(ns, inode->i_uid) && ns_capable(ns, CAP_FOWNER)) + if (kuid_has_mapping(ns, i_uid) && ns_capable(ns, CAP_FOWNER)) return true; return false; } diff --git a/fs/jfs/ioctl.c b/fs/jfs/ioctl.c index 10ee0ecca1a8..2581d4db58ff 100644 --- a/fs/jfs/ioctl.c +++ b/fs/jfs/ioctl.c @@ -76,7 +76,7 @@ long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) if (err) return err; - if (!inode_owner_or_capable(inode)) { + if (!inode_owner_or_capable(&init_user_ns, inode)) { err = -EACCES; goto setflags_out; } diff --git a/fs/jfs/jfs_inode.c b/fs/jfs/jfs_inode.c index 4cef170630db..59379089e939 100644 --- a/fs/jfs/jfs_inode.c +++ b/fs/jfs/jfs_inode.c @@ -64,7 +64,7 @@ struct inode *ialloc(struct inode *parent, umode_t mode) goto fail_put; } - inode_init_owner(inode, parent, mode); + inode_init_owner(&init_user_ns, inode, parent, mode); /* * New inodes need to save sane values on disk when * uid & gid mount options are used diff --git a/fs/minix/bitmap.c b/fs/minix/bitmap.c index f4e5e5181a14..9115948c624e 100644 --- a/fs/minix/bitmap.c +++ b/fs/minix/bitmap.c @@ -252,7 +252,7 @@ struct inode *minix_new_inode(const struct inode *dir, umode_t mode, int *error) iput(inode); return NULL; } - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode->i_ino = j; inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); inode->i_blocks = 0; diff --git a/fs/namei.c b/fs/namei.c index d78d74f5f5af..04b001ddade3 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1088,7 +1088,8 @@ int may_linkat(struct path *link) /* Source inode owner (or CAP_FOWNER) can hardlink all they like, * otherwise, it must be a safe source. */ - if (safe_hardlink_source(inode) || inode_owner_or_capable(inode)) + if (safe_hardlink_source(inode) || + inode_owner_or_capable(&init_user_ns, inode)) return 0; audit_log_path_denied(AUDIT_ANOM_LINK, "linkat"); @@ -2940,7 +2941,7 @@ static int may_open(const struct path *path, int acc_mode, int flag) } /* O_NOATIME can only be set by the owner or superuser */ - if (flag & O_NOATIME && !inode_owner_or_capable(inode)) + if (flag & O_NOATIME && !inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; return 0; diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c index b6517220cad5..11225a659736 100644 --- a/fs/nilfs2/inode.c +++ b/fs/nilfs2/inode.c @@ -348,7 +348,7 @@ struct inode *nilfs_new_inode(struct inode *dir, umode_t mode) /* reference count of i_bh inherits from nilfs_mdt_read_block() */ atomic64_inc(&root->inodes_count); - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode->i_ino = ino; inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c index 07d26f61f22a..b053b40315bf 100644 --- a/fs/nilfs2/ioctl.c +++ b/fs/nilfs2/ioctl.c @@ -132,7 +132,7 @@ static int nilfs_ioctl_setflags(struct inode *inode, struct file *filp, unsigned int flags, oldflags; int ret; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; if (get_user(flags, (int __user *)argp)) diff --git a/fs/ocfs2/dlmfs/dlmfs.c b/fs/ocfs2/dlmfs/dlmfs.c index 583820ec63e2..37c7d03a6284 100644 --- a/fs/ocfs2/dlmfs/dlmfs.c +++ b/fs/ocfs2/dlmfs/dlmfs.c @@ -329,7 +329,7 @@ static struct inode *dlmfs_get_root_inode(struct super_block *sb) if (inode) { inode->i_ino = get_next_ino(); - inode_init_owner(inode, NULL, mode); + inode_init_owner(&init_user_ns, inode, NULL, mode); inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); inc_nlink(inode); @@ -352,7 +352,7 @@ static struct inode *dlmfs_get_inode(struct inode *parent, return NULL; inode->i_ino = get_next_ino(); - inode_init_owner(inode, parent, mode); + inode_init_owner(&init_user_ns, inode, parent, mode); inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); ip = DLMFS_I(inode); diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c index 89984172fc4a..50c9b30ee9f6 100644 --- a/fs/ocfs2/ioctl.c +++ b/fs/ocfs2/ioctl.c @@ -96,7 +96,7 @@ static int ocfs2_set_inode_attr(struct inode *inode, unsigned flags, } status = -EACCES; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) goto bail_unlock; if (!S_ISDIR(inode->i_mode)) diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c index 2a237ab00453..908b79e1082b 100644 --- a/fs/ocfs2/namei.c +++ b/fs/ocfs2/namei.c @@ -198,7 +198,7 @@ static struct inode *ocfs2_get_init_inode(struct inode *dir, umode_t mode) * callers. */ if (S_ISDIR(mode)) set_nlink(inode, 2); - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); status = dquot_initialize(inode); if (status) return ERR_PTR(status); diff --git a/fs/omfs/inode.c b/fs/omfs/inode.c index ce93ccca8639..2a0e83236c01 100644 --- a/fs/omfs/inode.c +++ b/fs/omfs/inode.c @@ -48,7 +48,7 @@ struct inode *omfs_new_inode(struct inode *dir, umode_t mode) goto fail; inode->i_ino = new_block; - inode_init_owner(inode, NULL, mode); + inode_init_owner(&init_user_ns, inode, NULL, mode); inode->i_mapping->a_ops = &omfs_aops; inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index 28a075b5f5b2..98a23353b19a 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -636,7 +636,7 @@ static int ovl_create_object(struct dentry *dentry, int mode, dev_t rdev, inode->i_state |= I_CREATING; spin_unlock(&inode->i_lock); - inode_init_owner(inode, dentry->d_parent->d_inode, mode); + inode_init_owner(&init_user_ns, inode, dentry->d_parent->d_inode, mode); attr.mode = inode->i_mode; err = ovl_create_or_link(dentry, inode, &attr, false); diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index b2948e7b3210..7d8b84c715b3 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -54,7 +54,7 @@ static struct file *ovl_open_realfile(const struct file *file, if (err) { realfile = ERR_PTR(err); } else { - if (!inode_owner_or_capable(realinode)) + if (!inode_owner_or_capable(&init_user_ns, realinode)) flags &= ~O_NOATIME; realfile = open_with_fake_path(&file->f_path, flags, realinode, @@ -520,7 +520,7 @@ static long ovl_ioctl_set_flags(struct file *file, unsigned int cmd, long ret; struct inode *inode = file_inode(file); - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; ret = mnt_want_write_file(file); diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 88d877787770..3e925deaa19a 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -1005,7 +1005,7 @@ ovl_posix_acl_xattr_set(const struct xattr_handler *handler, goto out_acl_release; } err = -EPERM; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) goto out_acl_release; posix_acl_release(acl); diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c index de5c2047a0e9..06013b7b1e87 100644 --- a/fs/overlayfs/util.c +++ b/fs/overlayfs/util.c @@ -484,7 +484,7 @@ struct file *ovl_path_open(struct path *path, int flags) return ERR_PTR(err); /* O_NOATIME is an optimization, don't fail if not permitted */ - if (inode_owner_or_capable(inode)) + if (inode_owner_or_capable(&init_user_ns, inode)) flags |= O_NOATIME; return dentry_open(path, flags, current_cred()); diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 5d9fe2fb2953..9ce8214bfdac 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -874,7 +874,7 @@ set_posix_acl(struct inode *inode, int type, struct posix_acl *acl) if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode)) return acl ? -EACCES : 0; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; if (acl) { diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c index ee179a81b3da..3fd4326f36b5 100644 --- a/fs/ramfs/inode.c +++ b/fs/ramfs/inode.c @@ -67,7 +67,7 @@ struct inode *ramfs_get_inode(struct super_block *sb, if (inode) { inode->i_ino = get_next_ino(); - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode->i_mapping->a_ops = &ramfs_aops; mapping_set_gfp_mask(inode->i_mapping, GFP_HIGHUSER); mapping_set_unevictable(inode->i_mapping); diff --git a/fs/reiserfs/ioctl.c b/fs/reiserfs/ioctl.c index adb21bea3d60..4f1cbd930179 100644 --- a/fs/reiserfs/ioctl.c +++ b/fs/reiserfs/ioctl.c @@ -59,7 +59,7 @@ long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) if (err) break; - if (!inode_owner_or_capable(inode)) { + if (!inode_owner_or_capable(&init_user_ns, inode)) { err = -EPERM; goto setflags_out; } @@ -101,7 +101,7 @@ setflags_out: err = put_user(inode->i_generation, (int __user *)arg); break; case REISERFS_IOC_SETVERSION: - if (!inode_owner_or_capable(inode)) { + if (!inode_owner_or_capable(&init_user_ns, inode)) { err = -EPERM; break; } diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c index 1594687582f0..a67a7d371725 100644 --- a/fs/reiserfs/namei.c +++ b/fs/reiserfs/namei.c @@ -615,7 +615,7 @@ static int new_inode_init(struct inode *inode, struct inode *dir, umode_t mode) * the quota init calls have to know who to charge the quota to, so * we have to set uid and gid here */ - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); return dquot_initialize(inode); } diff --git a/fs/sysv/ialloc.c b/fs/sysv/ialloc.c index 6c9801986af6..50df794a3c1f 100644 --- a/fs/sysv/ialloc.c +++ b/fs/sysv/ialloc.c @@ -163,7 +163,7 @@ struct inode * sysv_new_inode(const struct inode * dir, umode_t mode) *sbi->s_sb_fic_count = cpu_to_fs16(sbi, count); fs16_add(sbi, sbi->s_sb_total_free_inodes, -1); dirty_sb(sb); - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode->i_ino = fs16_to_cpu(sbi, ino); inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); inode->i_blocks = 0; diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c index 9a6b8660425a..694e7714545b 100644 --- a/fs/ubifs/dir.c +++ b/fs/ubifs/dir.c @@ -94,7 +94,7 @@ struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir, */ inode->i_flags |= S_NOCMTIME; - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); inode->i_mapping->nrpages = 0; diff --git a/fs/ubifs/ioctl.c b/fs/ubifs/ioctl.c index 4363d85a3fd4..2326d5122beb 100644 --- a/fs/ubifs/ioctl.c +++ b/fs/ubifs/ioctl.c @@ -155,7 +155,7 @@ long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) if (IS_RDONLY(inode)) return -EROFS; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EACCES; if (get_user(flags, (int __user *) arg)) diff --git a/fs/udf/ialloc.c b/fs/udf/ialloc.c index 84ed23edebfd..2ecf0e87660e 100644 --- a/fs/udf/ialloc.c +++ b/fs/udf/ialloc.c @@ -103,7 +103,7 @@ struct inode *udf_new_inode(struct inode *dir, umode_t mode) mutex_unlock(&sbi->s_alloc_mutex); } - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET)) inode->i_uid = sbi->s_uid; if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET)) diff --git a/fs/ufs/ialloc.c b/fs/ufs/ialloc.c index 969fd60436d3..7e3e08c0166f 100644 --- a/fs/ufs/ialloc.c +++ b/fs/ufs/ialloc.c @@ -289,7 +289,7 @@ cg_found: ufs_mark_sb_dirty(sb); inode->i_ino = cg * uspi->s_ipg + bit; - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode->i_blocks = 0; inode->i_generation = 0; inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); diff --git a/fs/xattr.c b/fs/xattr.c index 56151bd9e642..c669922e1bde 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -127,7 +127,8 @@ xattr_permission(struct inode *inode, const char *name, int mask) if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode)) return (mask & MAY_WRITE) ? -EPERM : -ENODATA; if (S_ISDIR(inode->i_mode) && (inode->i_mode & S_ISVTX) && - (mask & MAY_WRITE) && !inode_owner_or_capable(inode)) + (mask & MAY_WRITE) && + !inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; } diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 97bd29fc8c43..218e80afc859 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -1300,7 +1300,7 @@ xfs_ioctl_setattr_get_trans( * The user ID of the calling process must be equal to the file owner * ID, except in cases where the CAP_FSETID capability is applicable. */ - if (!inode_owner_or_capable(VFS_I(ip))) { + if (!inode_owner_or_capable(&init_user_ns, VFS_I(ip))) { error = -EPERM; goto out_cancel; } diff --git a/fs/zonefs/super.c b/fs/zonefs/super.c index bec47f2d074b..569525ee8f69 100644 --- a/fs/zonefs/super.c +++ b/fs/zonefs/super.c @@ -1223,7 +1223,7 @@ static void zonefs_init_dir_inode(struct inode *parent, struct inode *inode, struct super_block *sb = parent->i_sb; inode->i_ino = blkdev_nr_zones(sb->s_bdev->bd_disk) + type + 1; - inode_init_owner(inode, parent, S_IFDIR | 0555); + inode_init_owner(&init_user_ns, inode, parent, S_IFDIR | 0555); inode->i_op = &zonefs_dir_inode_operations; inode->i_fop = &simple_dir_operations; set_nlink(inode, 2); diff --git a/include/linux/fs.h b/include/linux/fs.h index a85dfe6962df..2a9d4af6a64d 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1762,8 +1762,8 @@ static inline bool sb_start_intwrite_trylock(struct super_block *sb) return __sb_start_write_trylock(sb, SB_FREEZE_FS); } - -extern bool inode_owner_or_capable(const struct inode *inode); +bool inode_owner_or_capable(struct user_namespace *mnt_userns, + const struct inode *inode); /* * VFS helper functions.. @@ -1805,8 +1805,8 @@ extern long compat_ptr_ioctl(struct file *file, unsigned int cmd, /* * VFS file helper functions. */ -extern void inode_init_owner(struct inode *inode, const struct inode *dir, - umode_t mode); +void inode_init_owner(struct user_namespace *mnt_userns, struct inode *inode, + const struct inode *dir, umode_t mode); extern bool may_open_dev(const struct path *path); /* diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c index e3226b65f5dc..05b1f51d15e0 100644 --- a/kernel/bpf/inode.c +++ b/kernel/bpf/inode.c @@ -122,7 +122,7 @@ static struct inode *bpf_get_inode(struct super_block *sb, inode->i_mtime = inode->i_atime; inode->i_ctime = inode->i_atime; - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); return inode; } diff --git a/mm/madvise.c b/mm/madvise.c index 175c5582d8a9..d4f5eece9d56 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -539,7 +539,8 @@ static inline bool can_do_pageout(struct vm_area_struct *vma) * otherwise we'd be including shared non-exclusive mappings, which * opens a side channel. */ - return inode_owner_or_capable(file_inode(vma->vm_file)) || + return inode_owner_or_capable(&init_user_ns, + file_inode(vma->vm_file)) || file_permission(vma->vm_file, MAY_WRITE) == 0; } diff --git a/mm/mincore.c b/mm/mincore.c index 7bdb4673f776..9122676b54d6 100644 --- a/mm/mincore.c +++ b/mm/mincore.c @@ -166,7 +166,8 @@ static inline bool can_do_mincore(struct vm_area_struct *vma) * for writing; otherwise we'd be including shared non-exclusive * mappings, which opens a side channel. */ - return inode_owner_or_capable(file_inode(vma->vm_file)) || + return inode_owner_or_capable(&init_user_ns, + file_inode(vma->vm_file)) || file_permission(vma->vm_file, MAY_WRITE) == 0; } diff --git a/mm/shmem.c b/mm/shmem.c index 7c6b6d8f6c39..1c68c9edba5e 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2303,7 +2303,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode inode = new_inode(sb); if (inode) { inode->i_ino = ino; - inode_init_owner(inode, dir, mode); + inode_init_owner(&init_user_ns, inode, dir, mode); inode->i_blocks = 0; inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); inode->i_generation = prandom_u32(); diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 644b17ec9e63..9d6d3da2caf2 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3140,13 +3140,13 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name, } if (!selinux_initialized(&selinux_state)) - return (inode_owner_or_capable(inode) ? 0 : -EPERM); + return (inode_owner_or_capable(&init_user_ns, inode) ? 0 : -EPERM); sbsec = inode->i_sb->s_security; if (!(sbsec->flags & SBLABEL_MNT)) return -EOPNOTSUPP; - if (!inode_owner_or_capable(inode)) + if (!inode_owner_or_capable(&init_user_ns, inode)) return -EPERM; ad.type = LSM_AUDIT_DATA_DENTRY; -- cgit From c7c7a1a18af4c3bb7749d33e3df3acdf0a95bbb5 Mon Sep 17 00:00:00 2001 From: Tycho Andersen Date: Thu, 21 Jan 2021 14:19:28 +0100 Subject: xattr: handle idmapped mounts When interacting with extended attributes the vfs verifies that the caller is privileged over the inode with which the extended attribute is associated. For posix access and posix default extended attributes a uid or gid can be stored on-disk. Let the functions handle posix extended attributes on idmapped mounts. If the inode is accessed through an idmapped mount we need to map it according to the mount's user namespace. Afterwards the checks are identical to non-idmapped mounts. This has no effect for e.g. security xattrs since they don't store uids or gids and don't perform permission checks on them like posix acls do. Link: https://lore.kernel.org/r/20210121131959.646623-10-christian.brauner@ubuntu.com Cc: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig Reviewed-by: James Morris Signed-off-by: Tycho Andersen Signed-off-by: Christian Brauner --- fs/cachefiles/xattr.c | 29 ++++---- fs/ecryptfs/crypto.c | 4 +- fs/ecryptfs/inode.c | 5 +- fs/ecryptfs/mmap.c | 4 +- fs/nfsd/vfs.c | 14 ++-- fs/overlayfs/copy_up.c | 14 ++-- fs/overlayfs/dir.c | 2 +- fs/overlayfs/inode.c | 9 +-- fs/overlayfs/overlayfs.h | 6 +- fs/overlayfs/super.c | 6 +- fs/xattr.c | 120 +++++++++++++++++++--------------- include/linux/xattr.h | 27 +++++--- security/apparmor/domain.c | 4 +- security/commoncap.c | 6 +- security/integrity/evm/evm_crypto.c | 11 ++-- security/integrity/evm/evm_main.c | 4 +- security/integrity/ima/ima_appraise.c | 8 +-- security/selinux/hooks.c | 3 +- security/smack/smack_lsm.c | 8 ++- 19 files changed, 160 insertions(+), 124 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c index 72e42438f3d7..a591b5e09637 100644 --- a/fs/cachefiles/xattr.c +++ b/fs/cachefiles/xattr.c @@ -39,8 +39,8 @@ int cachefiles_check_object_type(struct cachefiles_object *object) _enter("%p{%s}", object, type); /* attempt to install a type label directly */ - ret = vfs_setxattr(dentry, cachefiles_xattr_cache, type, 2, - XATTR_CREATE); + ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache, type, + 2, XATTR_CREATE); if (ret == 0) { _debug("SET"); /* we succeeded */ goto error; @@ -54,7 +54,8 @@ int cachefiles_check_object_type(struct cachefiles_object *object) } /* read the current type label */ - ret = vfs_getxattr(dentry, cachefiles_xattr_cache, xtype, 3); + ret = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache, xtype, + 3); if (ret < 0) { if (ret == -ERANGE) goto bad_type_length; @@ -110,9 +111,8 @@ int cachefiles_set_object_xattr(struct cachefiles_object *object, _debug("SET #%u", auxdata->len); clear_bit(FSCACHE_COOKIE_AUX_UPDATED, &object->fscache.cookie->flags); - ret = vfs_setxattr(dentry, cachefiles_xattr_cache, - &auxdata->type, auxdata->len, - XATTR_CREATE); + ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache, + &auxdata->type, auxdata->len, XATTR_CREATE); if (ret < 0 && ret != -ENOMEM) cachefiles_io_error_obj( object, @@ -140,9 +140,8 @@ int cachefiles_update_object_xattr(struct cachefiles_object *object, _debug("SET #%u", auxdata->len); clear_bit(FSCACHE_COOKIE_AUX_UPDATED, &object->fscache.cookie->flags); - ret = vfs_setxattr(dentry, cachefiles_xattr_cache, - &auxdata->type, auxdata->len, - XATTR_REPLACE); + ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache, + &auxdata->type, auxdata->len, XATTR_REPLACE); if (ret < 0 && ret != -ENOMEM) cachefiles_io_error_obj( object, @@ -171,7 +170,7 @@ int cachefiles_check_auxdata(struct cachefiles_object *object) if (!auxbuf) return -ENOMEM; - xlen = vfs_getxattr(dentry, cachefiles_xattr_cache, + xlen = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache, &auxbuf->type, 512 + 1); ret = -ESTALE; if (xlen < 1 || @@ -213,7 +212,7 @@ int cachefiles_check_object_xattr(struct cachefiles_object *object, } /* read the current type label */ - ret = vfs_getxattr(dentry, cachefiles_xattr_cache, + ret = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache, &auxbuf->type, 512 + 1); if (ret < 0) { if (ret == -ENODATA) @@ -270,9 +269,9 @@ int cachefiles_check_object_xattr(struct cachefiles_object *object, } /* update the current label */ - ret = vfs_setxattr(dentry, cachefiles_xattr_cache, - &auxdata->type, auxdata->len, - XATTR_REPLACE); + ret = vfs_setxattr(&init_user_ns, dentry, + cachefiles_xattr_cache, &auxdata->type, + auxdata->len, XATTR_REPLACE); if (ret < 0) { cachefiles_io_error_obj(object, "Can't update xattr on %lu" @@ -309,7 +308,7 @@ int cachefiles_remove_object_xattr(struct cachefiles_cache *cache, { int ret; - ret = vfs_removexattr(dentry, cachefiles_xattr_cache); + ret = vfs_removexattr(&init_user_ns, dentry, cachefiles_xattr_cache); if (ret < 0) { if (ret == -ENOENT || ret == -ENODATA) ret = 0; diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c index 0681540c48d9..943e523f4c9d 100644 --- a/fs/ecryptfs/crypto.c +++ b/fs/ecryptfs/crypto.c @@ -1110,8 +1110,8 @@ ecryptfs_write_metadata_to_xattr(struct dentry *ecryptfs_dentry, } inode_lock(lower_inode); - rc = __vfs_setxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME, - page_virt, size, 0); + rc = __vfs_setxattr(&init_user_ns, lower_dentry, lower_inode, + ECRYPTFS_XATTR_NAME, page_virt, size, 0); if (!rc && ecryptfs_inode) fsstack_copy_attr_all(ecryptfs_inode, lower_inode); inode_unlock(lower_inode); diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index ac6472a82567..b9ccc4085d46 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -1024,7 +1024,8 @@ ecryptfs_setxattr(struct dentry *dentry, struct inode *inode, rc = -EOPNOTSUPP; goto out; } - rc = vfs_setxattr(lower_dentry, name, value, size, flags); + rc = vfs_setxattr(&init_user_ns, lower_dentry, name, value, size, + flags); if (!rc && inode) fsstack_copy_attr_all(inode, d_inode(lower_dentry)); out: @@ -1089,7 +1090,7 @@ static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode, goto out; } inode_lock(lower_inode); - rc = __vfs_removexattr(lower_dentry, name); + rc = __vfs_removexattr(&init_user_ns, lower_dentry, name); inode_unlock(lower_inode); out: return rc; diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c index 019572c6b39a..2f333a40ff4d 100644 --- a/fs/ecryptfs/mmap.c +++ b/fs/ecryptfs/mmap.c @@ -426,8 +426,8 @@ static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode) if (size < 0) size = 8; put_unaligned_be64(i_size_read(ecryptfs_inode), xattr_virt); - rc = __vfs_setxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME, - xattr_virt, size, 0); + rc = __vfs_setxattr(&init_user_ns, lower_dentry, lower_inode, + ECRYPTFS_XATTR_NAME, xattr_virt, size, 0); inode_unlock(lower_inode); if (rc) printk(KERN_ERR "Error whilst attempting to write inode size " diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 1905b39be1c2..37d85046b4d6 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -499,7 +499,8 @@ int nfsd4_is_junction(struct dentry *dentry) return 0; if (!(inode->i_mode & S_ISVTX)) return 0; - if (vfs_getxattr(dentry, NFSD_JUNCTION_XATTR_NAME, NULL, 0) <= 0) + if (vfs_getxattr(&init_user_ns, dentry, NFSD_JUNCTION_XATTR_NAME, + NULL, 0) <= 0) return 0; return 1; } @@ -2149,7 +2150,7 @@ nfsd_getxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name, inode_lock_shared(inode); - len = vfs_getxattr(dentry, name, NULL, 0); + len = vfs_getxattr(&init_user_ns, dentry, name, NULL, 0); /* * Zero-length attribute, just return. @@ -2176,7 +2177,7 @@ nfsd_getxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name, goto out; } - len = vfs_getxattr(dentry, name, buf, len); + len = vfs_getxattr(&init_user_ns, dentry, name, buf, len); if (len <= 0) { kvfree(buf); buf = NULL; @@ -2283,7 +2284,8 @@ nfsd_removexattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name) fh_lock(fhp); - ret = __vfs_removexattr_locked(fhp->fh_dentry, name, NULL); + ret = __vfs_removexattr_locked(&init_user_ns, fhp->fh_dentry, + name, NULL); fh_unlock(fhp); fh_drop_write(fhp); @@ -2307,8 +2309,8 @@ nfsd_setxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name, return nfserrno(ret); fh_lock(fhp); - ret = __vfs_setxattr_locked(fhp->fh_dentry, name, buf, len, flags, - NULL); + ret = __vfs_setxattr_locked(&init_user_ns, fhp->fh_dentry, name, buf, + len, flags, NULL); fh_unlock(fhp); fh_drop_write(fhp); diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index 3e9957ae19fa..f81b836c2256 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -85,9 +85,9 @@ int ovl_copy_xattr(struct super_block *sb, struct dentry *old, if (ovl_is_private_xattr(sb, name)) continue; retry: - size = vfs_getxattr(old, name, value, value_size); + size = vfs_getxattr(&init_user_ns, old, name, value, value_size); if (size == -ERANGE) - size = vfs_getxattr(old, name, NULL, 0); + size = vfs_getxattr(&init_user_ns, old, name, NULL, 0); if (size < 0) { error = size; @@ -114,7 +114,7 @@ retry: error = 0; continue; /* Discard */ } - error = vfs_setxattr(new, name, value, size, 0); + error = vfs_setxattr(&init_user_ns, new, name, value, size, 0); if (error) { if (error != -EOPNOTSUPP || ovl_must_copy_xattr(name)) break; @@ -795,7 +795,7 @@ static ssize_t ovl_getxattr(struct dentry *dentry, char *name, char **value) ssize_t res; char *buf; - res = vfs_getxattr(dentry, name, NULL, 0); + res = vfs_getxattr(&init_user_ns, dentry, name, NULL, 0); if (res == -ENODATA || res == -EOPNOTSUPP) res = 0; @@ -804,7 +804,7 @@ static ssize_t ovl_getxattr(struct dentry *dentry, char *name, char **value) if (!buf) return -ENOMEM; - res = vfs_getxattr(dentry, name, buf, res); + res = vfs_getxattr(&init_user_ns, dentry, name, buf, res); if (res < 0) kfree(buf); else @@ -846,8 +846,8 @@ static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c) * don't want that to happen for normal copy-up operation. */ if (capability) { - err = vfs_setxattr(upperpath.dentry, XATTR_NAME_CAPS, - capability, cap_size, 0); + err = vfs_setxattr(&init_user_ns, upperpath.dentry, + XATTR_NAME_CAPS, capability, cap_size, 0); if (err) goto out_free; } diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index 29840820a46c..d75c96cb18c3 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -449,7 +449,7 @@ static int ovl_set_upper_acl(struct dentry *upperdentry, const char *name, if (err < 0) goto out_free; - err = vfs_setxattr(upperdentry, name, buffer, size, XATTR_CREATE); + err = vfs_setxattr(&init_user_ns, upperdentry, name, buffer, size, XATTR_CREATE); out_free: kfree(buffer); return err; diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 5aa66881dbd7..023fde466e3a 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -352,7 +352,7 @@ int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name, goto out; if (!value && !upperdentry) { - err = vfs_getxattr(realdentry, name, NULL, 0); + err = vfs_getxattr(&init_user_ns, realdentry, name, NULL, 0); if (err < 0) goto out_drop_write; } @@ -367,10 +367,11 @@ int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name, old_cred = ovl_override_creds(dentry->d_sb); if (value) - err = vfs_setxattr(realdentry, name, value, size, flags); + err = vfs_setxattr(&init_user_ns, realdentry, name, value, size, + flags); else { WARN_ON(flags != XATTR_REPLACE); - err = vfs_removexattr(realdentry, name); + err = vfs_removexattr(&init_user_ns, realdentry, name); } revert_creds(old_cred); @@ -392,7 +393,7 @@ int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name, ovl_i_dentry_upper(inode) ?: ovl_dentry_lower(dentry); old_cred = ovl_override_creds(dentry->d_sb); - res = vfs_getxattr(realdentry, name, value, size); + res = vfs_getxattr(&init_user_ns, realdentry, name, value, size); revert_creds(old_cred); return res; } diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index b487e48c7fd4..0002834f664a 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -186,7 +186,7 @@ static inline ssize_t ovl_do_getxattr(struct ovl_fs *ofs, struct dentry *dentry, size_t size) { const char *name = ovl_xattr(ofs, ox); - return vfs_getxattr(dentry, name, value, size); + return vfs_getxattr(&init_user_ns, dentry, name, value, size); } static inline int ovl_do_setxattr(struct ovl_fs *ofs, struct dentry *dentry, @@ -194,7 +194,7 @@ static inline int ovl_do_setxattr(struct ovl_fs *ofs, struct dentry *dentry, size_t size) { const char *name = ovl_xattr(ofs, ox); - int err = vfs_setxattr(dentry, name, value, size, 0); + int err = vfs_setxattr(&init_user_ns, dentry, name, value, size, 0); pr_debug("setxattr(%pd2, \"%s\", \"%*pE\", %zu, 0) = %i\n", dentry, name, min((int)size, 48), value, size, err); return err; @@ -204,7 +204,7 @@ static inline int ovl_do_removexattr(struct ovl_fs *ofs, struct dentry *dentry, enum ovl_xattr ox) { const char *name = ovl_xattr(ofs, ox); - int err = vfs_removexattr(dentry, name); + int err = vfs_removexattr(&init_user_ns, dentry, name); pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry, name, err); return err; } diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index e24c995c5fd4..8168ab2dda11 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -794,11 +794,13 @@ retry: * allowed as upper are limited to "normal" ones, where checking * for the above two errors is sufficient. */ - err = vfs_removexattr(work, XATTR_NAME_POSIX_ACL_DEFAULT); + err = vfs_removexattr(&init_user_ns, work, + XATTR_NAME_POSIX_ACL_DEFAULT); if (err && err != -ENODATA && err != -EOPNOTSUPP) goto out_dput; - err = vfs_removexattr(work, XATTR_NAME_POSIX_ACL_ACCESS); + err = vfs_removexattr(&init_user_ns, work, + XATTR_NAME_POSIX_ACL_ACCESS); if (err && err != -ENODATA && err != -EOPNOTSUPP) goto out_dput; diff --git a/fs/xattr.c b/fs/xattr.c index d777025121e0..a49541713b11 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -83,7 +83,8 @@ xattr_resolve_name(struct inode *inode, const char **name) * because different namespaces have very different rules. */ static int -xattr_permission(struct inode *inode, const char *name, int mask) +xattr_permission(struct user_namespace *mnt_userns, struct inode *inode, + const char *name, int mask) { /* * We can never set or remove an extended attribute on a read-only @@ -128,11 +129,11 @@ xattr_permission(struct inode *inode, const char *name, int mask) return (mask & MAY_WRITE) ? -EPERM : -ENODATA; if (S_ISDIR(inode->i_mode) && (inode->i_mode & S_ISVTX) && (mask & MAY_WRITE) && - !inode_owner_or_capable(&init_user_ns, inode)) + !inode_owner_or_capable(mnt_userns, inode)) return -EPERM; } - return inode_permission(&init_user_ns, inode, mask); + return inode_permission(mnt_userns, inode, mask); } /* @@ -163,8 +164,9 @@ xattr_supported_namespace(struct inode *inode, const char *prefix) EXPORT_SYMBOL(xattr_supported_namespace); int -__vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name, - const void *value, size_t size, int flags) +__vfs_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, + struct inode *inode, const char *name, const void *value, + size_t size, int flags) { const struct xattr_handler *handler; @@ -175,7 +177,7 @@ __vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name, return -EOPNOTSUPP; if (size == 0) value = ""; /* empty EA, do not remove */ - return handler->set(handler, &init_user_ns, dentry, inode, name, value, + return handler->set(handler, mnt_userns, dentry, inode, name, value, size, flags); } EXPORT_SYMBOL(__vfs_setxattr); @@ -184,6 +186,7 @@ EXPORT_SYMBOL(__vfs_setxattr); * __vfs_setxattr_noperm - perform setxattr operation without performing * permission checks. * + * @mnt_userns - user namespace of the mount the inode was found from * @dentry - object to perform setxattr on * @name - xattr name to set * @value - value to set @name to @@ -196,8 +199,9 @@ EXPORT_SYMBOL(__vfs_setxattr); * is executed. It also assumes that the caller will make the appropriate * permission checks. */ -int __vfs_setxattr_noperm(struct dentry *dentry, const char *name, - const void *value, size_t size, int flags) +int __vfs_setxattr_noperm(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name, + const void *value, size_t size, int flags) { struct inode *inode = dentry->d_inode; int error = -EAGAIN; @@ -207,7 +211,8 @@ int __vfs_setxattr_noperm(struct dentry *dentry, const char *name, if (issec) inode->i_flags &= ~S_NOSEC; if (inode->i_opflags & IOP_XATTR) { - error = __vfs_setxattr(dentry, inode, name, value, size, flags); + error = __vfs_setxattr(mnt_userns, dentry, inode, name, value, + size, flags); if (!error) { fsnotify_xattr(dentry); security_inode_post_setxattr(dentry, name, value, @@ -246,14 +251,14 @@ int __vfs_setxattr_noperm(struct dentry *dentry, const char *name, * a delegation was broken on, NULL if none. */ int -__vfs_setxattr_locked(struct dentry *dentry, const char *name, - const void *value, size_t size, int flags, - struct inode **delegated_inode) +__vfs_setxattr_locked(struct user_namespace *mnt_userns, struct dentry *dentry, + const char *name, const void *value, size_t size, + int flags, struct inode **delegated_inode) { struct inode *inode = dentry->d_inode; int error; - error = xattr_permission(inode, name, MAY_WRITE); + error = xattr_permission(mnt_userns, inode, name, MAY_WRITE); if (error) return error; @@ -265,7 +270,8 @@ __vfs_setxattr_locked(struct dentry *dentry, const char *name, if (error) goto out; - error = __vfs_setxattr_noperm(dentry, name, value, size, flags); + error = __vfs_setxattr_noperm(mnt_userns, dentry, name, value, + size, flags); out: return error; @@ -273,8 +279,8 @@ out: EXPORT_SYMBOL_GPL(__vfs_setxattr_locked); int -vfs_setxattr(struct dentry *dentry, const char *name, const void *value, - size_t size, int flags) +vfs_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, + const char *name, const void *value, size_t size, int flags) { struct inode *inode = dentry->d_inode; struct inode *delegated_inode = NULL; @@ -282,7 +288,7 @@ vfs_setxattr(struct dentry *dentry, const char *name, const void *value, int error; if (size && strcmp(name, XATTR_NAME_CAPS) == 0) { - error = cap_convert_nscap(&init_user_ns, dentry, &value, size); + error = cap_convert_nscap(mnt_userns, dentry, &value, size); if (error < 0) return error; size = error; @@ -290,8 +296,8 @@ vfs_setxattr(struct dentry *dentry, const char *name, const void *value, retry_deleg: inode_lock(inode); - error = __vfs_setxattr_locked(dentry, name, value, size, flags, - &delegated_inode); + error = __vfs_setxattr_locked(mnt_userns, dentry, name, value, size, + flags, &delegated_inode); inode_unlock(inode); if (delegated_inode) { @@ -341,15 +347,16 @@ out_noalloc: * Returns the result of alloc, if failed, or the getxattr operation. */ ssize_t -vfs_getxattr_alloc(struct dentry *dentry, const char *name, char **xattr_value, - size_t xattr_size, gfp_t flags) +vfs_getxattr_alloc(struct user_namespace *mnt_userns, struct dentry *dentry, + const char *name, char **xattr_value, size_t xattr_size, + gfp_t flags) { const struct xattr_handler *handler; struct inode *inode = dentry->d_inode; char *value = *xattr_value; int error; - error = xattr_permission(inode, name, MAY_READ); + error = xattr_permission(mnt_userns, inode, name, MAY_READ); if (error) return error; @@ -390,12 +397,13 @@ __vfs_getxattr(struct dentry *dentry, struct inode *inode, const char *name, EXPORT_SYMBOL(__vfs_getxattr); ssize_t -vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size) +vfs_getxattr(struct user_namespace *mnt_userns, struct dentry *dentry, + const char *name, void *value, size_t size) { struct inode *inode = dentry->d_inode; int error; - error = xattr_permission(inode, name, MAY_READ); + error = xattr_permission(mnt_userns, inode, name, MAY_READ); if (error) return error; @@ -441,7 +449,8 @@ vfs_listxattr(struct dentry *dentry, char *list, size_t size) EXPORT_SYMBOL_GPL(vfs_listxattr); int -__vfs_removexattr(struct dentry *dentry, const char *name) +__vfs_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry, + const char *name) { struct inode *inode = d_inode(dentry); const struct xattr_handler *handler; @@ -451,8 +460,8 @@ __vfs_removexattr(struct dentry *dentry, const char *name) return PTR_ERR(handler); if (!handler->set) return -EOPNOTSUPP; - return handler->set(handler, &init_user_ns, dentry, inode, name, NULL, - 0, XATTR_REPLACE); + return handler->set(handler, mnt_userns, dentry, inode, name, NULL, 0, + XATTR_REPLACE); } EXPORT_SYMBOL(__vfs_removexattr); @@ -466,13 +475,14 @@ EXPORT_SYMBOL(__vfs_removexattr); * a delegation was broken on, NULL if none. */ int -__vfs_removexattr_locked(struct dentry *dentry, const char *name, - struct inode **delegated_inode) +__vfs_removexattr_locked(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name, + struct inode **delegated_inode) { struct inode *inode = dentry->d_inode; int error; - error = xattr_permission(inode, name, MAY_WRITE); + error = xattr_permission(mnt_userns, inode, name, MAY_WRITE); if (error) return error; @@ -484,7 +494,7 @@ __vfs_removexattr_locked(struct dentry *dentry, const char *name, if (error) goto out; - error = __vfs_removexattr(dentry, name); + error = __vfs_removexattr(mnt_userns, dentry, name); if (!error) { fsnotify_xattr(dentry); @@ -497,7 +507,8 @@ out: EXPORT_SYMBOL_GPL(__vfs_removexattr_locked); int -vfs_removexattr(struct dentry *dentry, const char *name) +vfs_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry, + const char *name) { struct inode *inode = dentry->d_inode; struct inode *delegated_inode = NULL; @@ -505,7 +516,8 @@ vfs_removexattr(struct dentry *dentry, const char *name) retry_deleg: inode_lock(inode); - error = __vfs_removexattr_locked(dentry, name, &delegated_inode); + error = __vfs_removexattr_locked(mnt_userns, dentry, + name, &delegated_inode); inode_unlock(inode); if (delegated_inode) { @@ -522,8 +534,9 @@ EXPORT_SYMBOL_GPL(vfs_removexattr); * Extended attribute SET operations */ static long -setxattr(struct dentry *d, const char __user *name, const void __user *value, - size_t size, int flags) +setxattr(struct user_namespace *mnt_userns, struct dentry *d, + const char __user *name, const void __user *value, size_t size, + int flags) { int error; void *kvalue = NULL; @@ -550,11 +563,10 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value, } if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) || (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0)) - posix_acl_fix_xattr_from_user(&init_user_ns, kvalue, - size); + posix_acl_fix_xattr_from_user(mnt_userns, kvalue, size); } - error = vfs_setxattr(d, kname, kvalue, size, flags); + error = vfs_setxattr(mnt_userns, d, kname, kvalue, size, flags); out: kvfree(kvalue); @@ -567,13 +579,15 @@ static int path_setxattr(const char __user *pathname, { struct path path; int error; + retry: error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); if (error) return error; error = mnt_want_write(path.mnt); if (!error) { - error = setxattr(path.dentry, name, value, size, flags); + error = setxattr(mnt_user_ns(path.mnt), path.dentry, name, + value, size, flags); mnt_drop_write(path.mnt); } path_put(&path); @@ -609,7 +623,9 @@ SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name, audit_file(f.file); error = mnt_want_write_file(f.file); if (!error) { - error = setxattr(f.file->f_path.dentry, name, value, size, flags); + error = setxattr(file_mnt_user_ns(f.file), + f.file->f_path.dentry, name, + value, size, flags); mnt_drop_write_file(f.file); } fdput(f); @@ -620,8 +636,8 @@ SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name, * Extended attribute GET operations */ static ssize_t -getxattr(struct dentry *d, const char __user *name, void __user *value, - size_t size) +getxattr(struct user_namespace *mnt_userns, struct dentry *d, + const char __user *name, void __user *value, size_t size) { ssize_t error; void *kvalue = NULL; @@ -641,12 +657,11 @@ getxattr(struct dentry *d, const char __user *name, void __user *value, return -ENOMEM; } - error = vfs_getxattr(d, kname, kvalue, size); + error = vfs_getxattr(mnt_userns, d, kname, kvalue, size); if (error > 0) { if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) || (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0)) - posix_acl_fix_xattr_to_user(&init_user_ns, kvalue, - error); + posix_acl_fix_xattr_to_user(mnt_userns, kvalue, error); if (size && copy_to_user(value, kvalue, error)) error = -EFAULT; } else if (error == -ERANGE && size >= XATTR_SIZE_MAX) { @@ -670,7 +685,7 @@ retry: error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); if (error) return error; - error = getxattr(path.dentry, name, value, size); + error = getxattr(mnt_user_ns(path.mnt), path.dentry, name, value, size); path_put(&path); if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; @@ -700,7 +715,8 @@ SYSCALL_DEFINE4(fgetxattr, int, fd, const char __user *, name, if (!f.file) return error; audit_file(f.file); - error = getxattr(f.file->f_path.dentry, name, value, size); + error = getxattr(file_mnt_user_ns(f.file), f.file->f_path.dentry, + name, value, size); fdput(f); return error; } @@ -784,7 +800,8 @@ SYSCALL_DEFINE3(flistxattr, int, fd, char __user *, list, size_t, size) * Extended attribute REMOVE operations */ static long -removexattr(struct dentry *d, const char __user *name) +removexattr(struct user_namespace *mnt_userns, struct dentry *d, + const char __user *name) { int error; char kname[XATTR_NAME_MAX + 1]; @@ -795,7 +812,7 @@ removexattr(struct dentry *d, const char __user *name) if (error < 0) return error; - return vfs_removexattr(d, kname); + return vfs_removexattr(mnt_userns, d, kname); } static int path_removexattr(const char __user *pathname, @@ -809,7 +826,7 @@ retry: return error; error = mnt_want_write(path.mnt); if (!error) { - error = removexattr(path.dentry, name); + error = removexattr(mnt_user_ns(path.mnt), path.dentry, name); mnt_drop_write(path.mnt); } path_put(&path); @@ -842,7 +859,8 @@ SYSCALL_DEFINE2(fremovexattr, int, fd, const char __user *, name) audit_file(f.file); error = mnt_want_write_file(f.file); if (!error) { - error = removexattr(f.file->f_path.dentry, name); + error = removexattr(file_mnt_user_ns(f.file), + f.file->f_path.dentry, name); mnt_drop_write_file(f.file); } fdput(f); diff --git a/include/linux/xattr.h b/include/linux/xattr.h index 260c9bcb0edb..4c379d23ec6e 100644 --- a/include/linux/xattr.h +++ b/include/linux/xattr.h @@ -16,6 +16,7 @@ #include #include #include +#include #include struct inode; @@ -49,18 +50,26 @@ struct xattr { }; ssize_t __vfs_getxattr(struct dentry *, struct inode *, const char *, void *, size_t); -ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t); +ssize_t vfs_getxattr(struct user_namespace *, struct dentry *, const char *, + void *, size_t); ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size); -int __vfs_setxattr(struct dentry *, struct inode *, const char *, const void *, size_t, int); -int __vfs_setxattr_noperm(struct dentry *, const char *, const void *, size_t, int); -int __vfs_setxattr_locked(struct dentry *, const char *, const void *, size_t, int, struct inode **); -int vfs_setxattr(struct dentry *, const char *, const void *, size_t, int); -int __vfs_removexattr(struct dentry *, const char *); -int __vfs_removexattr_locked(struct dentry *, const char *, struct inode **); -int vfs_removexattr(struct dentry *, const char *); +int __vfs_setxattr(struct user_namespace *, struct dentry *, struct inode *, + const char *, const void *, size_t, int); +int __vfs_setxattr_noperm(struct user_namespace *, struct dentry *, + const char *, const void *, size_t, int); +int __vfs_setxattr_locked(struct user_namespace *, struct dentry *, + const char *, const void *, size_t, int, + struct inode **); +int vfs_setxattr(struct user_namespace *, struct dentry *, const char *, + const void *, size_t, int); +int __vfs_removexattr(struct user_namespace *, struct dentry *, const char *); +int __vfs_removexattr_locked(struct user_namespace *, struct dentry *, + const char *, struct inode **); +int vfs_removexattr(struct user_namespace *, struct dentry *, const char *); ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size); -ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name, +ssize_t vfs_getxattr_alloc(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name, char **xattr_value, size_t size, gfp_t flags); int xattr_supported_namespace(struct inode *inode, const char *prefix); diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c index f919ebd042fd..16f184bc48de 100644 --- a/security/apparmor/domain.c +++ b/security/apparmor/domain.c @@ -324,8 +324,8 @@ static int aa_xattrs_match(const struct linux_binprm *bprm, d = bprm->file->f_path.dentry; for (i = 0; i < profile->xattr_count; i++) { - size = vfs_getxattr_alloc(d, profile->xattrs[i], &value, - value_size, GFP_KERNEL); + size = vfs_getxattr_alloc(&init_user_ns, d, profile->xattrs[i], + &value, value_size, GFP_KERNEL); if (size >= 0) { u32 perm; diff --git a/security/commoncap.c b/security/commoncap.c index c3fd9b86ea9a..745dc1f2c97f 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -313,7 +313,7 @@ int cap_inode_killpriv(struct dentry *dentry) { int error; - error = __vfs_removexattr(dentry, XATTR_NAME_CAPS); + error = __vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_CAPS); if (error == -EOPNOTSUPP) error = 0; return error; @@ -386,8 +386,8 @@ int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer, return -EINVAL; size = sizeof(struct vfs_ns_cap_data); - ret = (int) vfs_getxattr_alloc(dentry, XATTR_NAME_CAPS, - &tmpbuf, size, GFP_NOFS); + ret = (int)vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_CAPS, + &tmpbuf, size, GFP_NOFS); dput(dentry); if (ret < 0) diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c index 168c3b78ac47..f720f78cbbb1 100644 --- a/security/integrity/evm/evm_crypto.c +++ b/security/integrity/evm/evm_crypto.c @@ -222,7 +222,7 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry, ima_present = true; continue; } - size = vfs_getxattr_alloc(dentry, xattr->name, + size = vfs_getxattr_alloc(&init_user_ns, dentry, xattr->name, &xattr_value, xattr_size, GFP_NOFS); if (size == -ENOMEM) { error = -ENOMEM; @@ -275,8 +275,8 @@ static int evm_is_immutable(struct dentry *dentry, struct inode *inode) return 1; /* Do this the hard way */ - rc = vfs_getxattr_alloc(dentry, XATTR_NAME_EVM, (char **)&xattr_data, 0, - GFP_NOFS); + rc = vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_EVM, + (char **)&xattr_data, 0, GFP_NOFS); if (rc <= 0) { if (rc == -ENODATA) return 0; @@ -319,11 +319,12 @@ int evm_update_evmxattr(struct dentry *dentry, const char *xattr_name, xattr_value_len, &data); if (rc == 0) { data.hdr.xattr.sha1.type = EVM_XATTR_HMAC; - rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_EVM, + rc = __vfs_setxattr_noperm(&init_user_ns, dentry, + XATTR_NAME_EVM, &data.hdr.xattr.data[1], SHA1_DIGEST_SIZE + 1, 0); } else if (rc == -ENODATA && (inode->i_opflags & IOP_XATTR)) { - rc = __vfs_removexattr(dentry, XATTR_NAME_EVM); + rc = __vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_EVM); } return rc; } diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index 76d19146d74b..0de367aaa2d3 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -146,8 +146,8 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry, /* if status is not PASS, try to check again - against -ENOMEM */ /* first need to know the sig type */ - rc = vfs_getxattr_alloc(dentry, XATTR_NAME_EVM, (char **)&xattr_data, 0, - GFP_NOFS); + rc = vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_EVM, + (char **)&xattr_data, 0, GFP_NOFS); if (rc <= 0) { evm_status = INTEGRITY_FAIL; if (rc == -ENODATA) { diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 8361941ee0a1..70b643c41c6b 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -94,7 +94,7 @@ static int ima_fix_xattr(struct dentry *dentry, iint->ima_hash->xattr.ng.type = IMA_XATTR_DIGEST_NG; iint->ima_hash->xattr.ng.algo = algo; } - rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_IMA, + rc = __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_IMA, &iint->ima_hash->xattr.data[offset], (sizeof(iint->ima_hash->xattr) - offset) + iint->ima_hash->length, 0); @@ -215,8 +215,8 @@ int ima_read_xattr(struct dentry *dentry, { ssize_t ret; - ret = vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)xattr_value, - 0, GFP_NOFS); + ret = vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_IMA, + (char **)xattr_value, 0, GFP_NOFS); if (ret == -EOPNOTSUPP) ret = 0; return ret; @@ -520,7 +520,7 @@ void ima_inode_post_setattr(struct dentry *dentry) action = ima_must_appraise(inode, MAY_ACCESS, POST_SETATTR); if (!action) - __vfs_removexattr(dentry, XATTR_NAME_IMA); + __vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_IMA); iint = integrity_iint_find(inode); if (iint) { set_bit(IMA_CHANGE_ATTR, &iint->atomic_flags); diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 9d6d3da2caf2..2efedd7001b2 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6526,7 +6526,8 @@ static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen */ static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) { - return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); + return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SELINUX, + ctx, ctxlen, 0); } static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index f69c3dd9a0c6..746e5743accc 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -3425,7 +3425,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) */ if (isp->smk_flags & SMK_INODE_CHANGED) { isp->smk_flags &= ~SMK_INODE_CHANGED; - rc = __vfs_setxattr(dp, inode, + rc = __vfs_setxattr(&init_user_ns, dp, inode, XATTR_NAME_SMACKTRANSMUTE, TRANS_TRUE, TRANS_TRUE_SIZE, 0); @@ -4597,12 +4597,14 @@ static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) { - return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0); + return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, + ctxlen, 0); } static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) { - return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0); + return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SMACK, + ctx, ctxlen, 0); } static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) -- cgit From 71bc356f93a1c589fad13f7487258f89c417976e Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 21 Jan 2021 14:19:29 +0100 Subject: commoncap: handle idmapped mounts When interacting with user namespace and non-user namespace aware filesystem capabilities the vfs will perform various security checks to determine whether or not the filesystem capabilities can be used by the caller, whether they need to be removed and so on. The main infrastructure for this resides in the capability codepaths but they are called through the LSM security infrastructure even though they are not technically an LSM or optional. This extends the existing security hooks security_inode_removexattr(), security_inode_killpriv(), security_inode_getsecurity() to pass down the mount's user namespace and makes them aware of idmapped mounts. In order to actually get filesystem capabilities from disk the capability infrastructure exposes the get_vfs_caps_from_disk() helper. For user namespace aware filesystem capabilities a root uid is stored alongside the capabilities. In order to determine whether the caller can make use of the filesystem capability or whether it needs to be ignored it is translated according to the superblock's user namespace. If it can be translated to uid 0 according to that id mapping the caller can use the filesystem capabilities stored on disk. If we are accessing the inode that holds the filesystem capabilities through an idmapped mount we map the root uid according to the mount's user namespace. Afterwards the checks are identical to non-idmapped mounts: reading filesystem caps from disk enforces that the root uid associated with the filesystem capability must have a mapping in the superblock's user namespace and that the caller is either in the same user namespace or is a descendant of the superblock's user namespace. For filesystems that are mountable inside user namespace the caller can just mount the filesystem and won't usually need to idmap it. If they do want to idmap it they can create an idmapped mount and mark it with a user namespace they created and which is thus a descendant of s_user_ns. For filesystems that are not mountable inside user namespaces the descendant rule is trivially true because the s_user_ns will be the initial user namespace. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-11-christian.brauner@ubuntu.com Cc: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig Acked-by: James Morris Signed-off-by: Christian Brauner --- fs/attr.c | 2 +- fs/xattr.c | 18 ++++++++----- include/linux/capability.h | 4 ++- include/linux/lsm_hook_defs.h | 15 ++++++----- include/linux/lsm_hooks.h | 1 + include/linux/security.h | 54 +++++++++++++++++++++++-------------- kernel/auditsc.c | 5 ++-- security/commoncap.c | 62 ++++++++++++++++++++++++++++++++++--------- security/security.c | 25 ++++++++++------- security/selinux/hooks.c | 20 ++++++++------ security/smack/smack_lsm.c | 14 +++++----- 11 files changed, 146 insertions(+), 74 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/fs/attr.c b/fs/attr.c index f4543d2abdfb..c2d3bc0869d4 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -143,7 +143,7 @@ kill_priv: if (ia_valid & ATTR_KILL_PRIV) { int error; - error = security_inode_killpriv(dentry); + error = security_inode_killpriv(mnt_userns, dentry); if (error) return error; } diff --git a/fs/xattr.c b/fs/xattr.c index a49541713b11..79c439d31eaa 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -262,7 +262,8 @@ __vfs_setxattr_locked(struct user_namespace *mnt_userns, struct dentry *dentry, if (error) return error; - error = security_inode_setxattr(dentry, name, value, size, flags); + error = security_inode_setxattr(mnt_userns, dentry, name, value, size, + flags); if (error) goto out; @@ -313,18 +314,20 @@ retry_deleg: EXPORT_SYMBOL_GPL(vfs_setxattr); static ssize_t -xattr_getsecurity(struct inode *inode, const char *name, void *value, - size_t size) +xattr_getsecurity(struct user_namespace *mnt_userns, struct inode *inode, + const char *name, void *value, size_t size) { void *buffer = NULL; ssize_t len; if (!value || !size) { - len = security_inode_getsecurity(inode, name, &buffer, false); + len = security_inode_getsecurity(mnt_userns, inode, name, + &buffer, false); goto out_noalloc; } - len = security_inode_getsecurity(inode, name, &buffer, true); + len = security_inode_getsecurity(mnt_userns, inode, name, &buffer, + true); if (len < 0) return len; if (size < len) { @@ -414,7 +417,8 @@ vfs_getxattr(struct user_namespace *mnt_userns, struct dentry *dentry, if (!strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN)) { const char *suffix = name + XATTR_SECURITY_PREFIX_LEN; - int ret = xattr_getsecurity(inode, suffix, value, size); + int ret = xattr_getsecurity(mnt_userns, inode, suffix, value, + size); /* * Only overwrite the return value if a security module * is actually active. @@ -486,7 +490,7 @@ __vfs_removexattr_locked(struct user_namespace *mnt_userns, if (error) return error; - error = security_inode_removexattr(dentry, name); + error = security_inode_removexattr(mnt_userns, dentry, name); if (error) goto out; diff --git a/include/linux/capability.h b/include/linux/capability.h index da21ef118b04..65efb74c3585 100644 --- a/include/linux/capability.h +++ b/include/linux/capability.h @@ -271,7 +271,9 @@ static inline bool checkpoint_restore_ns_capable(struct user_namespace *ns) } /* audit system wants to get cap info from files as well */ -extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps); +int get_vfs_caps_from_disk(struct user_namespace *mnt_userns, + const struct dentry *dentry, + struct cpu_vfs_cap_data *cpu_caps); int cap_convert_nscap(struct user_namespace *mnt_userns, struct dentry *dentry, const void **ivalue, size_t size); diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 7aaa753b8608..df4cdad6681e 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -133,17 +133,20 @@ LSM_HOOK(int, 0, inode_follow_link, struct dentry *dentry, struct inode *inode, LSM_HOOK(int, 0, inode_permission, struct inode *inode, int mask) LSM_HOOK(int, 0, inode_setattr, struct dentry *dentry, struct iattr *attr) LSM_HOOK(int, 0, inode_getattr, const struct path *path) -LSM_HOOK(int, 0, inode_setxattr, struct dentry *dentry, const char *name, - const void *value, size_t size, int flags) +LSM_HOOK(int, 0, inode_setxattr, struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name, const void *value, + size_t size, int flags) LSM_HOOK(void, LSM_RET_VOID, inode_post_setxattr, struct dentry *dentry, const char *name, const void *value, size_t size, int flags) LSM_HOOK(int, 0, inode_getxattr, struct dentry *dentry, const char *name) LSM_HOOK(int, 0, inode_listxattr, struct dentry *dentry) -LSM_HOOK(int, 0, inode_removexattr, struct dentry *dentry, const char *name) +LSM_HOOK(int, 0, inode_removexattr, struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name) LSM_HOOK(int, 0, inode_need_killpriv, struct dentry *dentry) -LSM_HOOK(int, 0, inode_killpriv, struct dentry *dentry) -LSM_HOOK(int, -EOPNOTSUPP, inode_getsecurity, struct inode *inode, - const char *name, void **buffer, bool alloc) +LSM_HOOK(int, 0, inode_killpriv, struct user_namespace *mnt_userns, + struct dentry *dentry) +LSM_HOOK(int, -EOPNOTSUPP, inode_getsecurity, struct user_namespace *mnt_userns, + struct inode *inode, const char *name, void **buffer, bool alloc) LSM_HOOK(int, -EOPNOTSUPP, inode_setsecurity, struct inode *inode, const char *name, const void *value, size_t size, int flags) LSM_HOOK(int, 0, inode_listsecurity, struct inode *inode, char *buffer, diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index a19adef1f088..98a5e263aabb 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -444,6 +444,7 @@ * @inode_killpriv: * The setuid bit is being removed. Remove similar security labels. * Called with the dentry->d_inode->i_mutex held. + * @mnt_userns: user namespace of the mount * @dentry is the dentry being changed. * Return 0 on success. If error is returned, then the operation * causing setuid bit removal is failed. diff --git a/include/linux/security.h b/include/linux/security.h index c35ea0ffccd9..4e4f6c31e413 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -145,13 +145,16 @@ extern int cap_capset(struct cred *new, const struct cred *old, const kernel_cap_t *inheritable, const kernel_cap_t *permitted); extern int cap_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file); -extern int cap_inode_setxattr(struct dentry *dentry, const char *name, - const void *value, size_t size, int flags); -extern int cap_inode_removexattr(struct dentry *dentry, const char *name); -extern int cap_inode_need_killpriv(struct dentry *dentry); -extern int cap_inode_killpriv(struct dentry *dentry); -extern int cap_inode_getsecurity(struct inode *inode, const char *name, - void **buffer, bool alloc); +int cap_inode_setxattr(struct dentry *dentry, const char *name, + const void *value, size_t size, int flags); +int cap_inode_removexattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name); +int cap_inode_need_killpriv(struct dentry *dentry); +int cap_inode_killpriv(struct user_namespace *mnt_userns, + struct dentry *dentry); +int cap_inode_getsecurity(struct user_namespace *mnt_userns, + struct inode *inode, const char *name, void **buffer, + bool alloc); extern int cap_mmap_addr(unsigned long addr); extern int cap_mmap_file(struct file *file, unsigned long reqprot, unsigned long prot, unsigned long flags); @@ -345,16 +348,21 @@ int security_inode_follow_link(struct dentry *dentry, struct inode *inode, int security_inode_permission(struct inode *inode, int mask); int security_inode_setattr(struct dentry *dentry, struct iattr *attr); int security_inode_getattr(const struct path *path); -int security_inode_setxattr(struct dentry *dentry, const char *name, +int security_inode_setxattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name, const void *value, size_t size, int flags); void security_inode_post_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags); int security_inode_getxattr(struct dentry *dentry, const char *name); int security_inode_listxattr(struct dentry *dentry); -int security_inode_removexattr(struct dentry *dentry, const char *name); +int security_inode_removexattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name); int security_inode_need_killpriv(struct dentry *dentry); -int security_inode_killpriv(struct dentry *dentry); -int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc); +int security_inode_killpriv(struct user_namespace *mnt_userns, + struct dentry *dentry); +int security_inode_getsecurity(struct user_namespace *mnt_userns, + struct inode *inode, const char *name, + void **buffer, bool alloc); int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags); int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size); void security_inode_getsecid(struct inode *inode, u32 *secid); @@ -831,8 +839,9 @@ static inline int security_inode_getattr(const struct path *path) return 0; } -static inline int security_inode_setxattr(struct dentry *dentry, - const char *name, const void *value, size_t size, int flags) +static inline int security_inode_setxattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name, const void *value, + size_t size, int flags) { return cap_inode_setxattr(dentry, name, value, size, flags); } @@ -852,10 +861,11 @@ static inline int security_inode_listxattr(struct dentry *dentry) return 0; } -static inline int security_inode_removexattr(struct dentry *dentry, - const char *name) +static inline int security_inode_removexattr(struct user_namespace *mnt_userns, + struct dentry *dentry, + const char *name) { - return cap_inode_removexattr(dentry, name); + return cap_inode_removexattr(mnt_userns, dentry, name); } static inline int security_inode_need_killpriv(struct dentry *dentry) @@ -863,14 +873,18 @@ static inline int security_inode_need_killpriv(struct dentry *dentry) return cap_inode_need_killpriv(dentry); } -static inline int security_inode_killpriv(struct dentry *dentry) +static inline int security_inode_killpriv(struct user_namespace *mnt_userns, + struct dentry *dentry) { - return cap_inode_killpriv(dentry); + return cap_inode_killpriv(mnt_userns, dentry); } -static inline int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) +static inline int security_inode_getsecurity(struct user_namespace *mnt_userns, + struct inode *inode, + const char *name, void **buffer, + bool alloc) { - return cap_inode_getsecurity(inode, name, buffer, alloc); + return cap_inode_getsecurity(mnt_userns, inode, name, buffer, alloc); } static inline int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags) diff --git a/kernel/auditsc.c b/kernel/auditsc.c index ce8c9e2279ba..fdfdd71405ff 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1930,7 +1930,7 @@ static inline int audit_copy_fcaps(struct audit_names *name, if (!dentry) return 0; - rc = get_vfs_caps_from_disk(dentry, &caps); + rc = get_vfs_caps_from_disk(&init_user_ns, dentry, &caps); if (rc) return rc; @@ -2481,7 +2481,8 @@ int __audit_log_bprm_fcaps(struct linux_binprm *bprm, ax->d.next = context->aux; context->aux = (void *)ax; - get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps); + get_vfs_caps_from_disk(&init_user_ns, + bprm->file->f_path.dentry, &vcaps); ax->fcap.permitted = vcaps.permitted; ax->fcap.inheritable = vcaps.inheritable; diff --git a/security/commoncap.c b/security/commoncap.c index 745dc1f2c97f..234b074c2c58 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -303,17 +303,25 @@ int cap_inode_need_killpriv(struct dentry *dentry) /** * cap_inode_killpriv - Erase the security markings on an inode - * @dentry: The inode/dentry to alter + * + * @mnt_userns: user namespace of the mount the inode was found from + * @dentry: The inode/dentry to alter * * Erase the privilege-enhancing security markings on an inode. * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then + * take care to map the inode according to @mnt_userns before checking + * permissions. On non-idmapped mounts or if permission checking is to be + * performed on the raw inode simply passs init_user_ns. + * * Returns 0 if successful, -ve on error. */ -int cap_inode_killpriv(struct dentry *dentry) +int cap_inode_killpriv(struct user_namespace *mnt_userns, struct dentry *dentry) { int error; - error = __vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_CAPS); + error = __vfs_removexattr(mnt_userns, dentry, XATTR_NAME_CAPS); if (error == -EOPNOTSUPP) error = 0; return error; @@ -366,7 +374,8 @@ static bool is_v3header(size_t size, const struct vfs_cap_data *cap) * by the integrity subsystem, which really wants the unconverted values - * so that's good. */ -int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer, +int cap_inode_getsecurity(struct user_namespace *mnt_userns, + struct inode *inode, const char *name, void **buffer, bool alloc) { int size, ret; @@ -386,7 +395,7 @@ int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer, return -EINVAL; size = sizeof(struct vfs_ns_cap_data); - ret = (int)vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_CAPS, + ret = (int)vfs_getxattr_alloc(mnt_userns, dentry, XATTR_NAME_CAPS, &tmpbuf, size, GFP_NOFS); dput(dentry); @@ -412,6 +421,9 @@ int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer, root = le32_to_cpu(nscap->rootid); kroot = make_kuid(fs_ns, root); + /* If this is an idmapped mount shift the kuid. */ + kroot = kuid_into_mnt(mnt_userns, kroot); + /* If the root kuid maps to a valid uid in current ns, then return * this as a nscap. */ mappedroot = from_kuid(current_user_ns(), kroot); @@ -595,10 +607,24 @@ static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps, return *effective ? ret : 0; } -/* +/** + * get_vfs_caps_from_disk - retrieve vfs caps from disk + * + * @mnt_userns: user namespace of the mount the inode was found from + * @dentry: dentry from which @inode is retrieved + * @cpu_caps: vfs capabilities + * * Extract the on-exec-apply capability sets for an executable file. + * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then + * take care to map the inode according to @mnt_userns before checking + * permissions. On non-idmapped mounts or if permission checking is to be + * performed on the raw inode simply passs init_user_ns. */ -int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps) +int get_vfs_caps_from_disk(struct user_namespace *mnt_userns, + const struct dentry *dentry, + struct cpu_vfs_cap_data *cpu_caps) { struct inode *inode = d_backing_inode(dentry); __u32 magic_etc; @@ -654,6 +680,7 @@ int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data /* Limit the caps to the mounter of the filesystem * or the more limited uid specified in the xattr. */ + rootkuid = kuid_into_mnt(mnt_userns, rootkuid); if (!rootid_owns_currentns(rootkuid)) return -ENODATA; @@ -699,7 +726,8 @@ static int get_file_caps(struct linux_binprm *bprm, struct file *file, if (!current_in_userns(file->f_path.mnt->mnt_sb->s_user_ns)) return 0; - rc = get_vfs_caps_from_disk(file->f_path.dentry, &vcaps); + rc = get_vfs_caps_from_disk(file_mnt_user_ns(file), + file->f_path.dentry, &vcaps); if (rc < 0) { if (rc == -EINVAL) printk(KERN_NOTICE "Invalid argument reading file caps for %s\n", @@ -964,16 +992,25 @@ int cap_inode_setxattr(struct dentry *dentry, const char *name, /** * cap_inode_removexattr - Determine whether an xattr may be removed - * @dentry: The inode/dentry being altered - * @name: The name of the xattr to be changed + * + * @mnt_userns: User namespace of the mount the inode was found from + * @dentry: The inode/dentry being altered + * @name: The name of the xattr to be changed * * Determine whether an xattr may be removed from an inode, returning 0 if * permission is granted, -ve if denied. * + * If the inode has been found through an idmapped mount the user namespace of + * the vfsmount must be passed through @mnt_userns. This function will then + * take care to map the inode according to @mnt_userns before checking + * permissions. On non-idmapped mounts or if permission checking is to be + * performed on the raw inode simply passs init_user_ns. + * * This is used to make sure security xattrs don't get removed by those who * aren't privileged to remove them. */ -int cap_inode_removexattr(struct dentry *dentry, const char *name) +int cap_inode_removexattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name) { struct user_namespace *user_ns = dentry->d_sb->s_user_ns; @@ -987,8 +1024,7 @@ int cap_inode_removexattr(struct dentry *dentry, const char *name) struct inode *inode = d_backing_inode(dentry); if (!inode) return -EINVAL; - if (!capable_wrt_inode_uidgid(&init_user_ns, inode, - CAP_SETFCAP)) + if (!capable_wrt_inode_uidgid(mnt_userns, inode, CAP_SETFCAP)) return -EPERM; return 0; } diff --git a/security/security.c b/security/security.c index 7b09cfbae94f..698a9f17bad7 100644 --- a/security/security.c +++ b/security/security.c @@ -1280,7 +1280,8 @@ int security_inode_getattr(const struct path *path) return call_int_hook(inode_getattr, 0, path); } -int security_inode_setxattr(struct dentry *dentry, const char *name, +int security_inode_setxattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { int ret; @@ -1291,8 +1292,8 @@ int security_inode_setxattr(struct dentry *dentry, const char *name, * SELinux and Smack integrate the cap call, * so assume that all LSMs supplying this call do so. */ - ret = call_int_hook(inode_setxattr, 1, dentry, name, value, size, - flags); + ret = call_int_hook(inode_setxattr, 1, mnt_userns, dentry, name, value, + size, flags); if (ret == 1) ret = cap_inode_setxattr(dentry, name, value, size, flags); @@ -1327,7 +1328,8 @@ int security_inode_listxattr(struct dentry *dentry) return call_int_hook(inode_listxattr, 0, dentry); } -int security_inode_removexattr(struct dentry *dentry, const char *name) +int security_inode_removexattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name) { int ret; @@ -1337,9 +1339,9 @@ int security_inode_removexattr(struct dentry *dentry, const char *name) * SELinux and Smack integrate the cap call, * so assume that all LSMs supplying this call do so. */ - ret = call_int_hook(inode_removexattr, 1, dentry, name); + ret = call_int_hook(inode_removexattr, 1, mnt_userns, dentry, name); if (ret == 1) - ret = cap_inode_removexattr(dentry, name); + ret = cap_inode_removexattr(mnt_userns, dentry, name); if (ret) return ret; ret = ima_inode_removexattr(dentry, name); @@ -1353,12 +1355,15 @@ int security_inode_need_killpriv(struct dentry *dentry) return call_int_hook(inode_need_killpriv, 0, dentry); } -int security_inode_killpriv(struct dentry *dentry) +int security_inode_killpriv(struct user_namespace *mnt_userns, + struct dentry *dentry) { - return call_int_hook(inode_killpriv, 0, dentry); + return call_int_hook(inode_killpriv, 0, mnt_userns, dentry); } -int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) +int security_inode_getsecurity(struct user_namespace *mnt_userns, + struct inode *inode, const char *name, + void **buffer, bool alloc) { struct security_hook_list *hp; int rc; @@ -1369,7 +1374,7 @@ int security_inode_getsecurity(struct inode *inode, const char *name, void **buf * Only one module will provide an attribute with a given name. */ hlist_for_each_entry(hp, &security_hook_heads.inode_getsecurity, list) { - rc = hp->hook.inode_getsecurity(inode, name, buffer, alloc); + rc = hp->hook.inode_getsecurity(mnt_userns, inode, name, buffer, alloc); if (rc != LSM_RET_DEFAULT(inode_getsecurity)) return rc; } diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 2efedd7001b2..9719dd124221 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3119,7 +3119,8 @@ static bool has_cap_mac_admin(bool audit) return true; } -static int selinux_inode_setxattr(struct dentry *dentry, const char *name, +static int selinux_inode_setxattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { struct inode *inode = d_backing_inode(dentry); @@ -3140,13 +3141,13 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name, } if (!selinux_initialized(&selinux_state)) - return (inode_owner_or_capable(&init_user_ns, inode) ? 0 : -EPERM); + return (inode_owner_or_capable(mnt_userns, inode) ? 0 : -EPERM); sbsec = inode->i_sb->s_security; if (!(sbsec->flags & SBLABEL_MNT)) return -EOPNOTSUPP; - if (!inode_owner_or_capable(&init_user_ns, inode)) + if (!inode_owner_or_capable(mnt_userns, inode)) return -EPERM; ad.type = LSM_AUDIT_DATA_DENTRY; @@ -3267,10 +3268,11 @@ static int selinux_inode_listxattr(struct dentry *dentry) return dentry_has_perm(cred, dentry, FILE__GETATTR); } -static int selinux_inode_removexattr(struct dentry *dentry, const char *name) +static int selinux_inode_removexattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name) { if (strcmp(name, XATTR_NAME_SELINUX)) { - int rc = cap_inode_removexattr(dentry, name); + int rc = cap_inode_removexattr(mnt_userns, dentry, name); if (rc) return rc; @@ -3336,7 +3338,9 @@ static int selinux_path_notify(const struct path *path, u64 mask, * * Permission check is handled by selinux_inode_getxattr hook. */ -static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) +static int selinux_inode_getsecurity(struct user_namespace *mnt_userns, + struct inode *inode, const char *name, + void **buffer, bool alloc) { u32 size; int error; @@ -6533,8 +6537,8 @@ static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) { int len = 0; - len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, - ctx, true); + len = selinux_inode_getsecurity(&init_user_ns, inode, + XATTR_SELINUX_SUFFIX, ctx, true); if (len < 0) return len; *ctxlen = len; diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 746e5743accc..12a45e61c1a5 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -1240,7 +1240,8 @@ static int smack_inode_getattr(const struct path *path) * * Returns 0 if access is permitted, an error code otherwise */ -static int smack_inode_setxattr(struct dentry *dentry, const char *name, +static int smack_inode_setxattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { struct smk_audit_info ad; @@ -1362,7 +1363,8 @@ static int smack_inode_getxattr(struct dentry *dentry, const char *name) * * Returns 0 if access is permitted, an error code otherwise */ -static int smack_inode_removexattr(struct dentry *dentry, const char *name) +static int smack_inode_removexattr(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *name) { struct inode_smack *isp; struct smk_audit_info ad; @@ -1377,7 +1379,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name) if (!smack_privileged(CAP_MAC_ADMIN)) rc = -EPERM; } else - rc = cap_inode_removexattr(dentry, name); + rc = cap_inode_removexattr(mnt_userns, dentry, name); if (rc != 0) return rc; @@ -1420,9 +1422,9 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name) * * Returns the size of the attribute or an error code */ -static int smack_inode_getsecurity(struct inode *inode, - const char *name, void **buffer, - bool alloc) +static int smack_inode_getsecurity(struct user_namespace *mnt_userns, + struct inode *inode, const char *name, + void **buffer, bool alloc) { struct socket_smack *ssp; struct socket *sock; -- cgit