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path: root/fs/notify/fanotify/fanotify_user.c
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Diffstat (limited to 'fs/notify/fanotify/fanotify_user.c')
-rw-r--r--fs/notify/fanotify/fanotify_user.c468
1 files changed, 312 insertions, 156 deletions
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 69054886915b..56992b32c6bb 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -17,6 +17,8 @@
#include <linux/compat.h>
#include <linux/sched/signal.h>
#include <linux/memcontrol.h>
+#include <linux/statfs.h>
+#include <linux/exportfs.h>
#include <asm/ioctls.h>
@@ -47,33 +49,55 @@ struct kmem_cache *fanotify_mark_cache __read_mostly;
struct kmem_cache *fanotify_event_cachep __read_mostly;
struct kmem_cache *fanotify_perm_event_cachep __read_mostly;
+#define FANOTIFY_EVENT_ALIGN 4
+
+static int fanotify_event_info_len(struct fanotify_event *event)
+{
+ if (!fanotify_event_has_fid(event))
+ return 0;
+
+ return roundup(sizeof(struct fanotify_event_info_fid) +
+ sizeof(struct file_handle) + event->fh_len,
+ FANOTIFY_EVENT_ALIGN);
+}
+
/*
* Get an fsnotify notification event if one exists and is small
* enough to fit in "count". Return an error pointer if the count
- * is not large enough.
- *
- * Called with the group->notification_lock held.
+ * is not large enough. When permission event is dequeued, its state is
+ * updated accordingly.
*/
static struct fsnotify_event *get_one_event(struct fsnotify_group *group,
size_t count)
{
- assert_spin_locked(&group->notification_lock);
+ size_t event_size = FAN_EVENT_METADATA_LEN;
+ struct fsnotify_event *fsn_event = NULL;
pr_debug("%s: group=%p count=%zd\n", __func__, group, count);
+ spin_lock(&group->notification_lock);
if (fsnotify_notify_queue_is_empty(group))
- return NULL;
+ goto out;
- if (FAN_EVENT_METADATA_LEN > count)
- return ERR_PTR(-EINVAL);
+ if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) {
+ event_size += fanotify_event_info_len(
+ FANOTIFY_E(fsnotify_peek_first_event(group)));
+ }
- /* held the notification_lock the whole time, so this is the
- * same event we peeked above */
- return fsnotify_remove_first_event(group);
+ if (event_size > count) {
+ fsn_event = ERR_PTR(-EINVAL);
+ goto out;
+ }
+ fsn_event = fsnotify_remove_first_event(group);
+ if (fanotify_is_perm_event(FANOTIFY_E(fsn_event)->mask))
+ FANOTIFY_PE(fsn_event)->state = FAN_EVENT_REPORTED;
+out:
+ spin_unlock(&group->notification_lock);
+ return fsn_event;
}
static int create_fd(struct fsnotify_group *group,
- struct fanotify_event_info *event,
+ struct fanotify_event *event,
struct file **file)
{
int client_fd;
@@ -114,62 +138,32 @@ static int create_fd(struct fsnotify_group *group,
return client_fd;
}
-static int fill_event_metadata(struct fsnotify_group *group,
- struct fanotify_event_metadata *metadata,
- struct fsnotify_event *fsn_event,
- struct file **file)
-{
- int ret = 0;
- struct fanotify_event_info *event;
-
- pr_debug("%s: group=%p metadata=%p event=%p\n", __func__,
- group, metadata, fsn_event);
-
- *file = NULL;
- event = container_of(fsn_event, struct fanotify_event_info, fse);
- metadata->event_len = FAN_EVENT_METADATA_LEN;
- metadata->metadata_len = FAN_EVENT_METADATA_LEN;
- metadata->vers = FANOTIFY_METADATA_VERSION;
- metadata->reserved = 0;
- metadata->mask = fsn_event->mask & FAN_ALL_OUTGOING_EVENTS;
- metadata->pid = pid_vnr(event->tgid);
- if (unlikely(fsn_event->mask & FAN_Q_OVERFLOW))
- metadata->fd = FAN_NOFD;
- else {
- metadata->fd = create_fd(group, event, file);
- if (metadata->fd < 0)
- ret = metadata->fd;
- }
-
- return ret;
-}
-
-static struct fanotify_perm_event_info *dequeue_event(
- struct fsnotify_group *group, int fd)
+/*
+ * Finish processing of permission event by setting it to ANSWERED state and
+ * drop group->notification_lock.
+ */
+static void finish_permission_event(struct fsnotify_group *group,
+ struct fanotify_perm_event *event,
+ unsigned int response)
+ __releases(&group->notification_lock)
{
- struct fanotify_perm_event_info *event, *return_e = NULL;
-
- spin_lock(&group->notification_lock);
- list_for_each_entry(event, &group->fanotify_data.access_list,
- fae.fse.list) {
- if (event->fd != fd)
- continue;
+ bool destroy = false;
- list_del_init(&event->fae.fse.list);
- return_e = event;
- break;
- }
+ assert_spin_locked(&group->notification_lock);
+ event->response = response;
+ if (event->state == FAN_EVENT_CANCELED)
+ destroy = true;
+ else
+ event->state = FAN_EVENT_ANSWERED;
spin_unlock(&group->notification_lock);
-
- pr_debug("%s: found return_re=%p\n", __func__, return_e);
-
- return return_e;
+ if (destroy)
+ fsnotify_destroy_event(group, &event->fae.fse);
}
static int process_access_response(struct fsnotify_group *group,
struct fanotify_response *response_struct)
{
- struct fanotify_perm_event_info *event;
+ struct fanotify_perm_event *event;
int fd = response_struct->fd;
int response = response_struct->response;
@@ -191,45 +185,118 @@ static int process_access_response(struct fsnotify_group *group,
if (fd < 0)
return -EINVAL;
- if ((response & FAN_AUDIT) && !group->fanotify_data.audit)
+ if ((response & FAN_AUDIT) && !FAN_GROUP_FLAG(group, FAN_ENABLE_AUDIT))
return -EINVAL;
- event = dequeue_event(group, fd);
- if (!event)
- return -ENOENT;
+ spin_lock(&group->notification_lock);
+ list_for_each_entry(event, &group->fanotify_data.access_list,
+ fae.fse.list) {
+ if (event->fd != fd)
+ continue;
- event->response = response;
- wake_up(&group->fanotify_data.access_waitq);
+ list_del_init(&event->fae.fse.list);
+ finish_permission_event(group, event, response);
+ wake_up(&group->fanotify_data.access_waitq);
+ return 0;
+ }
+ spin_unlock(&group->notification_lock);
- return 0;
+ return -ENOENT;
}
-static ssize_t copy_event_to_user(struct fsnotify_group *group,
- struct fsnotify_event *event,
- char __user *buf)
+static int copy_fid_to_user(struct fanotify_event *event, char __user *buf)
{
- struct fanotify_event_metadata fanotify_event_metadata;
- struct file *f;
- int fd, ret;
+ struct fanotify_event_info_fid info = { };
+ struct file_handle handle = { };
+ size_t fh_len = event->fh_len;
+ size_t len = fanotify_event_info_len(event);
- pr_debug("%s: group=%p event=%p\n", __func__, group, event);
+ if (!len)
+ return 0;
- ret = fill_event_metadata(group, &fanotify_event_metadata, event, &f);
- if (ret < 0)
- return ret;
+ if (WARN_ON_ONCE(len < sizeof(info) + sizeof(handle) + fh_len))
+ return -EFAULT;
+
+ /* Copy event info fid header followed by vaiable sized file handle */
+ info.hdr.info_type = FAN_EVENT_INFO_TYPE_FID;
+ info.hdr.len = len;
+ info.fsid = event->fid.fsid;
+ if (copy_to_user(buf, &info, sizeof(info)))
+ return -EFAULT;
+
+ buf += sizeof(info);
+ len -= sizeof(info);
+ handle.handle_type = event->fh_type;
+ handle.handle_bytes = fh_len;
+ if (copy_to_user(buf, &handle, sizeof(handle)))
+ return -EFAULT;
+
+ buf += sizeof(handle);
+ len -= sizeof(handle);
+ if (copy_to_user(buf, fanotify_event_fh(event), fh_len))
+ return -EFAULT;
+
+ /* Pad with 0's */
+ buf += fh_len;
+ len -= fh_len;
+ WARN_ON_ONCE(len < 0 || len >= FANOTIFY_EVENT_ALIGN);
+ if (len > 0 && clear_user(buf, len))
+ return -EFAULT;
+
+ return 0;
+}
+
+static ssize_t copy_event_to_user(struct fsnotify_group *group,
+ struct fsnotify_event *fsn_event,
+ char __user *buf, size_t count)
+{
+ struct fanotify_event_metadata metadata;
+ struct fanotify_event *event;
+ struct file *f = NULL;
+ int ret, fd = FAN_NOFD;
+
+ pr_debug("%s: group=%p event=%p\n", __func__, group, fsn_event);
+
+ event = container_of(fsn_event, struct fanotify_event, fse);
+ metadata.event_len = FAN_EVENT_METADATA_LEN;
+ metadata.metadata_len = FAN_EVENT_METADATA_LEN;
+ metadata.vers = FANOTIFY_METADATA_VERSION;
+ metadata.reserved = 0;
+ metadata.mask = event->mask & FANOTIFY_OUTGOING_EVENTS;
+ metadata.pid = pid_vnr(event->pid);
+
+ if (fanotify_event_has_path(event)) {
+ fd = create_fd(group, event, &f);
+ if (fd < 0)
+ return fd;
+ } else if (fanotify_event_has_fid(event)) {
+ metadata.event_len += fanotify_event_info_len(event);
+ }
+ metadata.fd = fd;
- fd = fanotify_event_metadata.fd;
ret = -EFAULT;
- if (copy_to_user(buf, &fanotify_event_metadata,
- fanotify_event_metadata.event_len))
+ /*
+ * Sanity check copy size in case get_one_event() and
+ * fill_event_metadata() event_len sizes ever get out of sync.
+ */
+ if (WARN_ON_ONCE(metadata.event_len > count))
+ goto out_close_fd;
+
+ if (copy_to_user(buf, &metadata, FAN_EVENT_METADATA_LEN))
goto out_close_fd;
if (fanotify_is_perm_event(event->mask))
- FANOTIFY_PE(event)->fd = fd;
+ FANOTIFY_PE(fsn_event)->fd = fd;
- if (fd != FAN_NOFD)
+ if (fanotify_event_has_path(event)) {
fd_install(fd, f);
- return fanotify_event_metadata.event_len;
+ } else if (fanotify_event_has_fid(event)) {
+ ret = copy_fid_to_user(event, buf + FAN_EVENT_METADATA_LEN);
+ if (ret < 0)
+ return ret;
+ }
+
+ return metadata.event_len;
out_close_fd:
if (fd != FAN_NOFD) {
@@ -270,10 +337,7 @@ static ssize_t fanotify_read(struct file *file, char __user *buf,
add_wait_queue(&group->notification_waitq, &wait);
while (1) {
- spin_lock(&group->notification_lock);
kevent = get_one_event(group, count);
- spin_unlock(&group->notification_lock);
-
if (IS_ERR(kevent)) {
ret = PTR_ERR(kevent);
break;
@@ -295,7 +359,7 @@ static ssize_t fanotify_read(struct file *file, char __user *buf,
continue;
}
- ret = copy_event_to_user(group, kevent, buf);
+ ret = copy_event_to_user(group, kevent, buf, count);
if (unlikely(ret == -EOPENSTALE)) {
/*
* We cannot report events with stale fd so drop it.
@@ -310,11 +374,13 @@ static ssize_t fanotify_read(struct file *file, char __user *buf,
* Permission events get queued to wait for response. Other
* events can be destroyed now.
*/
- if (!fanotify_is_perm_event(kevent->mask)) {
+ if (!fanotify_is_perm_event(FANOTIFY_E(kevent)->mask)) {
fsnotify_destroy_event(group, kevent);
} else {
if (ret <= 0) {
- FANOTIFY_PE(kevent)->response = FAN_DENY;
+ spin_lock(&group->notification_lock);
+ finish_permission_event(group,
+ FANOTIFY_PE(kevent), FAN_DENY);
wake_up(&group->fanotify_data.access_waitq);
} else {
spin_lock(&group->notification_lock);
@@ -364,7 +430,7 @@ static ssize_t fanotify_write(struct file *file, const char __user *buf, size_t
static int fanotify_release(struct inode *ignored, struct file *file)
{
struct fsnotify_group *group = file->private_data;
- struct fanotify_perm_event_info *event, *next;
+ struct fanotify_perm_event *event;
struct fsnotify_event *fsn_event;
/*
@@ -379,13 +445,12 @@ static int fanotify_release(struct inode *ignored, struct file *file)
* and simulate reply from userspace.
*/
spin_lock(&group->notification_lock);
- list_for_each_entry_safe(event, next, &group->fanotify_data.access_list,
- fae.fse.list) {
- pr_debug("%s: found group=%p event=%p\n", __func__, group,
- event);
-
+ while (!list_empty(&group->fanotify_data.access_list)) {
+ event = list_first_entry(&group->fanotify_data.access_list,
+ struct fanotify_perm_event, fae.fse.list);
list_del_init(&event->fae.fse.list);
- event->response = FAN_ALLOW;
+ finish_permission_event(group, event, FAN_ALLOW);
+ spin_lock(&group->notification_lock);
}
/*
@@ -395,13 +460,14 @@ static int fanotify_release(struct inode *ignored, struct file *file)
*/
while (!fsnotify_notify_queue_is_empty(group)) {
fsn_event = fsnotify_remove_first_event(group);
- if (!(fsn_event->mask & FAN_ALL_PERM_EVENTS)) {
+ if (!(FANOTIFY_E(fsn_event)->mask & FANOTIFY_PERM_EVENTS)) {
spin_unlock(&group->notification_lock);
fsnotify_destroy_event(group, fsn_event);
- spin_lock(&group->notification_lock);
} else {
- FANOTIFY_PE(fsn_event)->response = FAN_ALLOW;
+ finish_permission_event(group, FANOTIFY_PE(fsn_event),
+ FAN_ALLOW);
}
+ spin_lock(&group->notification_lock);
}
spin_unlock(&group->notification_lock);
@@ -506,18 +572,10 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
spin_lock(&fsn_mark->lock);
if (!(flags & FAN_MARK_IGNORED_MASK)) {
- __u32 tmask = fsn_mark->mask & ~mask;
-
- if (flags & FAN_MARK_ONDIR)
- tmask &= ~FAN_ONDIR;
-
oldmask = fsn_mark->mask;
- fsn_mark->mask = tmask;
+ fsn_mark->mask &= ~mask;
} else {
- __u32 tmask = fsn_mark->ignored_mask & ~mask;
- if (flags & FAN_MARK_ONDIR)
- tmask &= ~FAN_ONDIR;
- fsn_mark->ignored_mask = tmask;
+ fsn_mark->ignored_mask &= ~mask;
}
*destroy = !(fsn_mark->mask | fsn_mark->ignored_mask);
spin_unlock(&fsn_mark->lock);
@@ -563,6 +621,13 @@ static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group,
mask, flags);
}
+static int fanotify_remove_sb_mark(struct fsnotify_group *group,
+ struct super_block *sb, __u32 mask,
+ unsigned int flags)
+{
+ return fanotify_remove_mark(group, &sb->s_fsnotify_marks, mask, flags);
+}
+
static int fanotify_remove_inode_mark(struct fsnotify_group *group,
struct inode *inode, __u32 mask,
unsigned int flags)
@@ -579,19 +644,10 @@ static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark,
spin_lock(&fsn_mark->lock);
if (!(flags & FAN_MARK_IGNORED_MASK)) {
- __u32 tmask = fsn_mark->mask | mask;
-
- if (flags & FAN_MARK_ONDIR)
- tmask |= FAN_ONDIR;
-
oldmask = fsn_mark->mask;
- fsn_mark->mask = tmask;
+ fsn_mark->mask |= mask;
} else {
- __u32 tmask = fsn_mark->ignored_mask | mask;
- if (flags & FAN_MARK_ONDIR)
- tmask |= FAN_ONDIR;
-
- fsn_mark->ignored_mask = tmask;
+ fsn_mark->ignored_mask |= mask;
if (flags & FAN_MARK_IGNORED_SURV_MODIFY)
fsn_mark->flags |= FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY;
}
@@ -602,7 +658,8 @@ static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark,
static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
fsnotify_connp_t *connp,
- unsigned int type)
+ unsigned int type,
+ __kernel_fsid_t *fsid)
{
struct fsnotify_mark *mark;
int ret;
@@ -615,7 +672,7 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
return ERR_PTR(-ENOMEM);
fsnotify_init_mark(mark, group);
- ret = fsnotify_add_mark_locked(mark, connp, type, 0);
+ ret = fsnotify_add_mark_locked(mark, connp, type, 0, fsid);
if (ret) {
fsnotify_put_mark(mark);
return ERR_PTR(ret);
@@ -627,7 +684,8 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
static int fanotify_add_mark(struct fsnotify_group *group,
fsnotify_connp_t *connp, unsigned int type,
- __u32 mask, unsigned int flags)
+ __u32 mask, unsigned int flags,
+ __kernel_fsid_t *fsid)
{
struct fsnotify_mark *fsn_mark;
__u32 added;
@@ -635,7 +693,7 @@ static int fanotify_add_mark(struct fsnotify_group *group,
mutex_lock(&group->mark_mutex);
fsn_mark = fsnotify_find_mark(connp, group);
if (!fsn_mark) {
- fsn_mark = fanotify_add_new_mark(group, connp, type);
+ fsn_mark = fanotify_add_new_mark(group, connp, type, fsid);
if (IS_ERR(fsn_mark)) {
mutex_unlock(&group->mark_mutex);
return PTR_ERR(fsn_mark);
@@ -652,15 +710,23 @@ static int fanotify_add_mark(struct fsnotify_group *group,
static int fanotify_add_vfsmount_mark(struct fsnotify_group *group,
struct vfsmount *mnt, __u32 mask,
- unsigned int flags)
+ unsigned int flags, __kernel_fsid_t *fsid)
{
return fanotify_add_mark(group, &real_mount(mnt)->mnt_fsnotify_marks,
- FSNOTIFY_OBJ_TYPE_VFSMOUNT, mask, flags);
+ FSNOTIFY_OBJ_TYPE_VFSMOUNT, mask, flags, fsid);
+}
+
+static int fanotify_add_sb_mark(struct fsnotify_group *group,
+ struct super_block *sb, __u32 mask,
+ unsigned int flags, __kernel_fsid_t *fsid)
+{
+ return fanotify_add_mark(group, &sb->s_fsnotify_marks,
+ FSNOTIFY_OBJ_TYPE_SB, mask, flags, fsid);
}
static int fanotify_add_inode_mark(struct fsnotify_group *group,
struct inode *inode, __u32 mask,
- unsigned int flags)
+ unsigned int flags, __kernel_fsid_t *fsid)
{
pr_debug("%s: group=%p inode=%p\n", __func__, group, inode);
@@ -671,11 +737,11 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group,
*/
if ((flags & FAN_MARK_IGNORED_MASK) &&
!(flags & FAN_MARK_IGNORED_SURV_MODIFY) &&
- (atomic_read(&inode->i_writecount) > 0))
+ inode_is_open_for_write(inode))
return 0;
return fanotify_add_mark(group, &inode->i_fsnotify_marks,
- FSNOTIFY_OBJ_TYPE_INODE, mask, flags);
+ FSNOTIFY_OBJ_TYPE_INODE, mask, flags, fsid);
}
/* fanotify syscalls */
@@ -684,18 +750,18 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
struct fsnotify_group *group;
int f_flags, fd;
struct user_struct *user;
- struct fanotify_event_info *oevent;
+ struct fanotify_event *oevent;
- pr_debug("%s: flags=%d event_f_flags=%d\n",
- __func__, flags, event_f_flags);
+ pr_debug("%s: flags=%x event_f_flags=%x\n",
+ __func__, flags, event_f_flags);
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
#ifdef CONFIG_AUDITSYSCALL
- if (flags & ~(FAN_ALL_INIT_FLAGS | FAN_ENABLE_AUDIT))
+ if (flags & ~(FANOTIFY_INIT_FLAGS | FAN_ENABLE_AUDIT))
#else
- if (flags & ~FAN_ALL_INIT_FLAGS)
+ if (flags & ~FANOTIFY_INIT_FLAGS)
#endif
return -EINVAL;
@@ -711,6 +777,10 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
return -EINVAL;
}
+ if ((flags & FAN_REPORT_FID) &&
+ (flags & FANOTIFY_CLASS_BITS) != FAN_CLASS_NOTIF)
+ return -EINVAL;
+
user = get_current_user();
if (atomic_read(&user->fanotify_listeners) > FANOTIFY_DEFAULT_MAX_LISTENERS) {
free_uid(user);
@@ -731,10 +801,12 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
}
group->fanotify_data.user = user;
+ group->fanotify_data.flags = flags;
atomic_inc(&user->fanotify_listeners);
group->memcg = get_mem_cgroup_from_mm(current->mm);
- oevent = fanotify_alloc_event(group, NULL, FS_Q_OVERFLOW, NULL);
+ oevent = fanotify_alloc_event(group, NULL, FS_Q_OVERFLOW, NULL,
+ FSNOTIFY_EVENT_NONE, NULL);
if (unlikely(!oevent)) {
fd = -ENOMEM;
goto out_destroy_group;
@@ -746,7 +818,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
group->fanotify_data.f_flags = event_f_flags;
init_waitqueue_head(&group->fanotify_data.access_waitq);
INIT_LIST_HEAD(&group->fanotify_data.access_list);
- switch (flags & FAN_ALL_CLASS_BITS) {
+ switch (flags & FANOTIFY_CLASS_BITS) {
case FAN_CLASS_NOTIF:
group->priority = FS_PRIO_0;
break;
@@ -783,7 +855,6 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
fd = -EPERM;
if (!capable(CAP_AUDIT_WRITE))
goto out_destroy_group;
- group->fanotify_data.audit = true;
}
fd = anon_inode_getfd("[fanotify]", &fanotify_fops, group, f_flags);
@@ -797,6 +868,48 @@ out_destroy_group:
return fd;
}
+/* Check if filesystem can encode a unique fid */
+static int fanotify_test_fid(struct path *path, __kernel_fsid_t *fsid)
+{
+ __kernel_fsid_t root_fsid;
+ int err;
+
+ /*
+ * Make sure path is not in filesystem with zero fsid (e.g. tmpfs).
+ */
+ err = vfs_get_fsid(path->dentry, fsid);
+ if (err)
+ return err;
+
+ if (!fsid->val[0] && !fsid->val[1])
+ return -ENODEV;
+
+ /*
+ * Make sure path is not inside a filesystem subvolume (e.g. btrfs)
+ * which uses a different fsid than sb root.
+ */
+ err = vfs_get_fsid(path->dentry->d_sb->s_root, &root_fsid);
+ if (err)
+ return err;
+
+ if (root_fsid.val[0] != fsid->val[0] ||
+ root_fsid.val[1] != fsid->val[1])
+ return -EXDEV;
+
+ /*
+ * We need to make sure that the file system supports at least
+ * encoding a file handle so user can use name_to_handle_at() to
+ * compare fid returned with event to the file handle of watched
+ * objects. However, name_to_handle_at() requires that the
+ * filesystem also supports decoding file handles.
+ */
+ if (!path->dentry->d_sb->s_export_op ||
+ !path->dentry->d_sb->s_export_op->fh_to_dentry)
+ return -EOPNOTSUPP;
+
+ return 0;
+}
+
static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
int dfd, const char __user *pathname)
{
@@ -805,7 +918,9 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
struct fsnotify_group *group;
struct fd f;
struct path path;
- u32 valid_mask = FAN_ALL_EVENTS | FAN_EVENT_ON_CHILD;
+ __kernel_fsid_t __fsid, *fsid = NULL;
+ u32 valid_mask = FANOTIFY_EVENTS | FANOTIFY_EVENT_FLAGS;
+ unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS;
int ret;
pr_debug("%s: fanotify_fd=%d flags=%x dfd=%d pathname=%p mask=%llx\n",
@@ -815,8 +930,18 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
if (mask & ((__u64)0xffffffff << 32))
return -EINVAL;
- if (flags & ~FAN_ALL_MARK_FLAGS)
+ if (flags & ~FANOTIFY_MARK_FLAGS)
+ return -EINVAL;
+
+ switch (mark_type) {
+ case FAN_MARK_INODE:
+ case FAN_MARK_MOUNT:
+ case FAN_MARK_FILESYSTEM:
+ break;
+ default:
return -EINVAL;
+ }
+
switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE | FAN_MARK_FLUSH)) {
case FAN_MARK_ADD: /* fallthrough */
case FAN_MARK_REMOVE:
@@ -824,20 +949,15 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
return -EINVAL;
break;
case FAN_MARK_FLUSH:
- if (flags & ~(FAN_MARK_MOUNT | FAN_MARK_FLUSH))
+ if (flags & ~(FANOTIFY_MARK_TYPE_BITS | FAN_MARK_FLUSH))
return -EINVAL;
break;
default:
return -EINVAL;
}
- if (mask & FAN_ONDIR) {
- flags |= FAN_MARK_ONDIR;
- mask &= ~FAN_ONDIR;
- }
-
if (IS_ENABLED(CONFIG_FANOTIFY_ACCESS_PERMISSIONS))
- valid_mask |= FAN_ALL_PERM_EVENTS;
+ valid_mask |= FANOTIFY_PERM_EVENTS;
if (mask & ~valid_mask)
return -EINVAL;
@@ -857,14 +977,28 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
* allowed to set permissions events.
*/
ret = -EINVAL;
- if (mask & FAN_ALL_PERM_EVENTS &&
+ if (mask & FANOTIFY_PERM_EVENTS &&
group->priority == FS_PRIO_0)
goto fput_and_out;
+ /*
+ * Events with data type inode do not carry enough information to report
+ * event->fd, so we do not allow setting a mask for inode events unless
+ * group supports reporting fid.
+ * inode events are not supported on a mount mark, because they do not
+ * carry enough information (i.e. path) to be filtered by mount point.
+ */
+ if (mask & FANOTIFY_INODE_EVENTS &&
+ (!FAN_GROUP_FLAG(group, FAN_REPORT_FID) ||
+ mark_type == FAN_MARK_MOUNT))
+ goto fput_and_out;
+
if (flags & FAN_MARK_FLUSH) {
ret = 0;
- if (flags & FAN_MARK_MOUNT)
+ if (mark_type == FAN_MARK_MOUNT)
fsnotify_clear_vfsmount_marks_by_group(group);
+ else if (mark_type == FAN_MARK_FILESYSTEM)
+ fsnotify_clear_sb_marks_by_group(group);
else
fsnotify_clear_inode_marks_by_group(group);
goto fput_and_out;
@@ -874,8 +1008,16 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
if (ret)
goto fput_and_out;
+ if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) {
+ ret = fanotify_test_fid(&path, &__fsid);
+ if (ret)
+ goto path_put_and_out;
+
+ fsid = &__fsid;
+ }
+
/* inode held in place by reference to path; group by fget on fd */
- if (!(flags & FAN_MARK_MOUNT))
+ if (mark_type == FAN_MARK_INODE)
inode = path.dentry->d_inode;
else
mnt = path.mnt;
@@ -883,21 +1025,32 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
/* create/update an inode mark */
switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE)) {
case FAN_MARK_ADD:
- if (flags & FAN_MARK_MOUNT)
- ret = fanotify_add_vfsmount_mark(group, mnt, mask, flags);
+ if (mark_type == FAN_MARK_MOUNT)
+ ret = fanotify_add_vfsmount_mark(group, mnt, mask,
+ flags, fsid);
+ else if (mark_type == FAN_MARK_FILESYSTEM)
+ ret = fanotify_add_sb_mark(group, mnt->mnt_sb, mask,
+ flags, fsid);
else
- ret = fanotify_add_inode_mark(group, inode, mask, flags);
+ ret = fanotify_add_inode_mark(group, inode, mask,
+ flags, fsid);
break;
case FAN_MARK_REMOVE:
- if (flags & FAN_MARK_MOUNT)
- ret = fanotify_remove_vfsmount_mark(group, mnt, mask, flags);
+ if (mark_type == FAN_MARK_MOUNT)
+ ret = fanotify_remove_vfsmount_mark(group, mnt, mask,
+ flags);
+ else if (mark_type == FAN_MARK_FILESYSTEM)
+ ret = fanotify_remove_sb_mark(group, mnt->mnt_sb, mask,
+ flags);
else
- ret = fanotify_remove_inode_mark(group, inode, mask, flags);
+ ret = fanotify_remove_inode_mark(group, inode, mask,
+ flags);
break;
default:
ret = -EINVAL;
}
+path_put_and_out:
path_put(&path);
fput_and_out:
fdput(f);
@@ -934,12 +1087,15 @@ COMPAT_SYSCALL_DEFINE6(fanotify_mark,
*/
static int __init fanotify_user_setup(void)
{
+ BUILD_BUG_ON(HWEIGHT32(FANOTIFY_INIT_FLAGS) != 8);
+ BUILD_BUG_ON(HWEIGHT32(FANOTIFY_MARK_FLAGS) != 9);
+
fanotify_mark_cache = KMEM_CACHE(fsnotify_mark,
SLAB_PANIC|SLAB_ACCOUNT);
- fanotify_event_cachep = KMEM_CACHE(fanotify_event_info, SLAB_PANIC);
+ fanotify_event_cachep = KMEM_CACHE(fanotify_event, SLAB_PANIC);
if (IS_ENABLED(CONFIG_FANOTIFY_ACCESS_PERMISSIONS)) {
fanotify_perm_event_cachep =
- KMEM_CACHE(fanotify_perm_event_info, SLAB_PANIC);
+ KMEM_CACHE(fanotify_perm_event, SLAB_PANIC);
}
return 0;