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2016-10-14ovl: explain error values when removing acl from workdirMiklos Szeredi1-0/+13
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-13Merge tag 'nfs-for-4.9-1' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds25-476/+1331
Pull NFS client updates from Anna Schumaker: "Highlights include: Stable bugfixes: - sunrpc: fix writ espace race causing stalls - NFS: Fix inode corruption in nfs_prime_dcache() - NFSv4: Don't report revoked delegations as valid in nfs_have_delegation() - NFSv4: nfs4_copy_delegation_stateid() must fail if the delegation is invalid - NFSv4: Open state recovery must account for file permission changes - NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic Features: - Add support for tracking multiple layout types with an ordered list - Add support for using multiple backchannel threads on the client - Add support for pNFS file layout session trunking - Delay xprtrdma use of DMA API (for device driver removal) - Add support for xprtrdma remote invalidation - Add support for larger xprtrdma inline thresholds - Use a scatter/gather list for sending xprtrdma RPC calls - Add support for the CB_NOTIFY_LOCK callback - Improve hashing sunrpc auth_creds by using both uid and gid Bugfixes: - Fix xprtrdma use of DMA API - Validate filenames before adding to the dcache - Fix corruption of xdr->nwords in xdr_copy_to_scratch - Fix setting buffer length in xdr_set_next_buffer() - Don't deadlock the state manager on the SEQUENCE status flags - Various delegation and stateid related fixes - Retry operations if an interrupted slot receives EREMOTEIO - Make nfs boot time y2038 safe" * tag 'nfs-for-4.9-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (100 commits) NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic fs: nfs: Make nfs boot time y2038 safe sunrpc: replace generic auth_cred hash with auth-specific function sunrpc: add RPCSEC_GSS hash_cred() function sunrpc: add auth_unix hash_cred() function sunrpc: add generic_auth hash_cred() function sunrpc: add hash_cred() function to rpc_authops struct Retry operation on EREMOTEIO on an interrupted slot pNFS: Fix atime updates on pNFS clients sunrpc: queue work on system_power_efficient_wq NFSv4.1: Even if the stateid is OK, we may need to recover the open modes NFSv4: If recovery failed for a specific open stateid, then don't retry NFSv4: Fix retry issues with nfs41_test/free_stateid NFSv4: Open state recovery must account for file permission changes NFSv4: Mark the lock and open stateids as invalid after freeing them NFSv4: Don't test open_stateid unless it is set NFSv4: nfs4_do_handle_exception() handle revoke/expiry of a single stateid NFS: Always call nfs_inode_find_state_and_recover() when revoking a delegation NFSv4: Fix a race when updating an open_stateid NFSv4: Fix a race in nfs_inode_reclaim_delegation() ...
2016-10-13Merge tag 'nfsd-4.9' of git://linux-nfs.org/~bfields/linuxLinus Torvalds17-53/+517
Pull nfsd updates from Bruce Fields: "Some RDMA work and some good bugfixes, and two new features that could benefit from user testing: - Anna Schumacker contributed a simple NFSv4.2 COPY implementation. COPY is already supported on the client side, so a call to copy_file_range() on a recent client should now result in a server-side copy that doesn't require all the data to make a round trip to the client and back. - Jeff Layton implemented callbacks to notify clients when contended locks become available, which should reduce latency on workloads with contended locks" * tag 'nfsd-4.9' of git://linux-nfs.org/~bfields/linux: NFSD: Implement the COPY call nfsd: handle EUCLEAN nfsd: only WARN once on unmapped errors exportfs: be careful to only return expected errors. nfsd4: setclientid_confirm with unmatched verifier should fail nfsd: randomize SETCLIENTID reply to help distinguish servers nfsd: set the MAY_NOTIFY_LOCK flag in OPEN replies nfs: add a new NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK constant nfsd: add a LRU list for blocked locks nfsd: have nfsd4_lock use blocking locks for v4.1+ locks nfsd: plumb in a CB_NOTIFY_LOCK operation NFSD: fix corruption in notifier registration svcrdma: support Remote Invalidation svcrdma: Server-side support for rpcrdma_connect_private rpcrdma: RDMA/CM private message data structure svcrdma: Skip put_page() when send_reply() fails svcrdma: Tail iovec leaves an orphaned DMA mapping nfsd: fix dprintk in nfsd4_encode_getdeviceinfo nfsd: eliminate cb_minorversion field nfsd: don't set a FL_LAYOUT lease for flexfiles layouts
2016-10-13Merge tag 'xfs-reflink-for-linus-4.9-rc1' of ↵Linus Torvalds73-308/+10557
git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs < XFS has gained super CoW powers! > ---------------------------------- \ ^__^ \ (oo)\_______ (__)\ )\/\ ||----w | || || Pull XFS support for shared data extents from Dave Chinner: "This is the second part of the XFS updates for this merge cycle. This pullreq contains the new shared data extents feature for XFS. Given the complexity and size of this change I am expecting - like the addition of reverse mapping last cycle - that there will be some follow-up bug fixes and cleanups around the -rc3 stage for issues that I'm sure will show up once the code hits a wider userbase. What it is: At the most basic level we are simply adding shared data extents to XFS - i.e. a single extent on disk can now have multiple owners. To do this we have to add new on-disk features to both track the shared extents and the number of times they've been shared. This is done by the new "refcount" btree that sits in every allocation group. When we share or unshare an extent, this tree gets updated. Along with this new tree, the reverse mapping tree needs to be updated to track each owner or a shared extent. This also needs to be updated ever share/unshare operation. These interactions at extent allocation and freeing time have complex ordering and recovery constraints, so there's a significant amount of new intent-based transaction code to ensure that operations are performed atomically from both the runtime and integrity/crash recovery perspectives. We also need to break sharing when writes hit a shared extent - this is where the new copy-on-write implementation comes in. We allocate new storage and copy the original data along with the overwrite data into the new location. We only do this for data as we don't share metadata at all - each inode has it's own metadata that tracks the shared data extents, the extents undergoing CoW and it's own private extents. Of course, being XFS, nothing is simple - we use delayed allocation for CoW similar to how we use it for normal writes. ENOSPC is a significant issue here - we build on the reservation code added in 4.8-rc1 with the reverse mapping feature to ensure we don't get spurious ENOSPC issues part way through a CoW operation. These mechanisms also help minimise fragmentation due to repeated CoW operations. To further reduce fragmentation overhead, we've also introduced a CoW extent size hint, which indicates how large a region we should allocate when we execute a CoW operation. With all this functionality in place, we can hook up .copy_file_range, .clone_file_range and .dedupe_file_range and we gain all the capabilities of reflink and other vfs provided functionality that enable manipulation to shared extents. We also added a fallocate mode that explicitly unshares a range of a file, which we implemented as an explicit CoW of all the shared extents in a file. As such, it's a huge chunk of new functionality with new on-disk format features and internal infrastructure. It warns at mount time as an experimental feature and that it may eat data (as we do with all new on-disk features until they stabilise). We have not released userspace suport for it yet - userspace support currently requires download from Darrick's xfsprogs repo and build from source, so the access to this feature is really developer/tester only at this point. Initial userspace support will be released at the same time the kernel with this code in it is released. The new code causes 5-6 new failures with xfstests - these aren't serious functional failures but things the output of tests changing slightly due to perturbations in layouts, space usage, etc. OTOH, we've added 150+ new tests to xfstests that specifically exercise this new functionality so it's got far better test coverage than any functionality we've previously added to XFS. Darrick has done a pretty amazing job getting us to this stage, and special mention also needs to go to Christoph (review, testing, improvements and bug fixes) and Brian (caught several intricate bugs during review) for the effort they've also put in. Summary: - unshare range (FALLOC_FL_UNSHARE) support for fallocate - copy-on-write extent size hints (FS_XFLAG_COWEXTSIZE) for fsxattr interface - shared extent support for XFS - copy-on-write support for shared extents - copy_file_range support - clone_file_range support (implements reflink) - dedupe_file_range support - defrag support for reverse mapping enabled filesystems" * tag 'xfs-reflink-for-linus-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (71 commits) xfs: convert COW blocks to real blocks before unwritten extent conversion xfs: rework refcount cow recovery error handling xfs: clear reflink flag if setting realtime flag xfs: fix error initialization xfs: fix label inaccuracies xfs: remove isize check from unshare operation xfs: reduce stack usage of _reflink_clear_inode_flag xfs: check inode reflink flag before calling reflink functions xfs: implement swapext for rmap filesystems xfs: refactor swapext code xfs: various swapext cleanups xfs: recognize the reflink feature bit xfs: simulate per-AG reservations being critically low xfs: don't mix reflink and DAX mode for now xfs: check for invalid inode reflink flags xfs: set a default CoW extent size of 32 blocks xfs: convert unwritten status of reverse mappings for shared files xfs: use interval query for rmap alloc operations on shared files xfs: add shared rmap map/unmap/convert log item types xfs: increase log reservations for reflink ...
2016-10-13CIFS: Reset read oplock to NONE if we have mandatory locks after reopenPavel Shilovsky1-0/+9
We are already doing the same thing for an ordinary open case: we can't keep read oplock on a file if we have mandatory byte-range locks because pagereading can conflict with these locks on a server. Fix it by setting oplock level to NONE. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <smfrench@gmail.com>
2016-10-13CIFS: Fix persistent handles re-opening on reconnectPavel Shilovsky2-5/+18
openFileList of tcon can be changed while cifs_reopen_file() is called that can lead to an unexpected behavior when we return to the loop. Fix this by introducing a temp list for keeping all file handles that need to be reopen. Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <smfrench@gmail.com>
2016-10-13SMB2: Separate RawNTLMSSP authentication from SMB2_sess_setupSachin Prabhu1-199/+162
We split the rawntlmssp authentication into negotiate and authencate parts. We also clean up the code and add helpers. Signed-off-by: Sachin Prabhu <sprabhu@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2016-10-13SMB2: Separate Kerberos authentication from SMB2_sess_setupSachin Prabhu1-46/+230
Add helper functions and split Kerberos authentication off SMB2_sess_setup. Signed-off-by: Sachin Prabhu <sprabhu@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2016-10-13Expose cifs module parameters in sysfsGermano Percossi1-3/+3
/sys/module/cifs/parameters should display the three other module load time configuration settings for cifs.ko Signed-off-by: Germano Percossi <germano.percossi@citrix.com> Signed-off-by: Steve French <steve.french@primarydata.com>
2016-10-13Cleanup missing frees on some ioctlsSteve French1-5/+4
Cleanup some missing mem frees on some cifs ioctls, and clarify others to make more obvious that no data is returned. CC: Stable <stable@vger.kernel.org> Signed-off-by: Steve French <smfrench@gmail.com> Acked-by: Sachin Prabhu <sprabhu@redhat.com>
2016-10-13Enable previous version supportSteve French4-2/+72
Add ioctl to query previous versions of file Allows listing snapshots on files on SMB3 mounts. Signed-off-by: Steve French <smfrench@gmail.com>
2016-10-13Do not send SMB3 SET_INFO request if nothing is changingSteve French1-0/+6
[CIFS] We had cases where we sent a SMB2/SMB3 setinfo request with all timestamp (and DOS attribute) fields marked as 0 (ie do not change) e.g. on chmod or chown. Signed-off-by: Steve French <steve.french@primarydata.com> CC: Stable <stable@vger.kernel.org>
2016-10-13Merge git://www.linux-watchdog.org/linux-watchdogLinus Torvalds1-0/+2
Pull watchdog updates from Wim Van Sebroeck: - a new watchdog pretimeout governor framework - support to upload the firmware on the ziirave_wdt - several fixes and cleanups * git://www.linux-watchdog.org/linux-watchdog: (26 commits) watchdog: imx2_wdt: add pretimeout function support watchdog: softdog: implement pretimeout support watchdog: pretimeout: add pretimeout_available_governors attribute watchdog: pretimeout: add option to select a pretimeout governor in runtime watchdog: pretimeout: add panic pretimeout governor watchdog: pretimeout: add noop pretimeout governor watchdog: add watchdog pretimeout governor framework watchdog: hpwdt: add support for iLO5 fs: compat_ioctl: add pretimeout functions for watchdogs watchdog: add pretimeout support to the core watchdog: imx2_wdt: use preferred BIT macro instead of open coded values watchdog: st_wdt: Remove support for obsolete platforms watchdog: bindings: Remove obsolete platforms from dt doc. watchdog: mt7621_wdt: Remove assignment of dev pointer watchdog: rt2880_wdt: Remove assignment of dev pointer watchdog: constify watchdog_ops structures watchdog: tegra: constify watchdog_ops structures watchdog: iTCO_wdt: constify iTCO_wdt_pm structure watchdog: cadence_wdt: Fix the suspend resume watchdog: txx9wdt: Add missing clock (un)prepare calls for CCF ...
2016-10-13pnfs/blocklayout: fix last_write_offset incorrectly set to page boundaryBenjamin Coddington1-1/+2
Commit 41963c10c47a35185e68cb9049f7a3493c94d2d7 sets the block layout's last written byte to the offset of the end of the extent rather than the end of the write which incorrectly updates the inode's size for partial-page writes. Fixes: 41963c10c47a ("pnfs/blocklayout: update last_write_offset atomically with extents") Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org # 4.8+ Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-10-13afs: call->operation_ID sometimes used as __be32 sometimes as u32David Howells3-6/+5
call->operation_ID is sometimes being used as __be32 sometimes is being used as u32. Be consistent and settle on using as u32. Signed-off-by: David Howells <dhowells@redhat.com.
2016-10-13afs: unmapping the wrong bufferDan Carpenter1-2/+2
We switched from kmap_atomic() to kmap() so the kunmap() calls need to be updated to match. Fixes: d001648ec7cf ('rxrpc: Don't expose skbs to in-kernel users [ver #2]') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-12fscrypto: make XTS tweak initialization endian-independentEric Biggers1-7/+8
The XTS tweak (or IV) was initialized differently on little endian and big endian systems. Because the ciphertext depends on the XTS tweak, it was not possible to use an encrypted filesystem created by a little endian system on a big endian system and vice versa, even if they shared the same PAGE_SIZE. Fix this by always using little endian. This will break hypothetical big endian users of ext4 or f2fs encryption. However, all users we are aware of are little endian, and it's believed that "real" big endian users are unlikely to exist yet. So this might as well be fixed now before it's too late. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
2016-10-12ext4: do not advertise encryption support when disabledEric Biggers1-0/+4
The sysfs file /sys/fs/ext4/features/encryption was present on kernels compiled with CONFIG_EXT4_FS_ENCRYPTION=n. This was misleading because such kernels do not actually support ext4 encryption. Therefore, only provide this file on kernels compiled with CONFIG_EXT4_FS_ENCRYPTION=y. Note: since the ext4 feature files are all hardcoded to have a contents of "supported", it really is the presence or absence of the file that is significant, not the contents (and this change reflects that). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
2016-10-12jbd2: fix incorrect unlock on j_list_lockTaesoo Kim1-1/+2
When 'jh->b_transaction == transaction' (asserted by below) J_ASSERT_JH(jh, (jh->b_transaction == transaction || ... 'journal->j_list_lock' will be incorrectly unlocked, since the the lock is aquired only at the end of if / else-if statements (missing the else case). Signed-off-by: Taesoo Kim <tsgatesv@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Fixes: 6e4862a5bb9d12be87e4ea5d9a60836ebed71d28 Cc: stable@vger.kernel.org # 3.14+
2016-10-12ext4: super.c: Update logging style using KERN_CONTJoe Perches1-10/+11
Recent commit require line continuing printks to use PR_CONT. Update super.c to use KERN_CONT and use vsprintf extension %pV to avoid a printk/vprintk/printk("\n") sequence as well. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
2016-10-12f2fs: fix wrong sum_page pointer in f2fs_gcJaegeuk Kim1-5/+5
This patch fixes using a wrong pointer for sum_page in f2fs_gc. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-10-12Merge branch 'fst-fixes' of ↵Chris Mason7-156/+261
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.9 Signed-off-by: Chris Mason <clm@fb.com>
2016-10-12SMB3: Add mount parameter to allow user to override max creditsSteve French5-16/+37
Add mount option "max_credits" to allow setting maximum SMB3 credits to any value from 10 to 64000 (default is 32000). This can be useful to workaround servers with problems allocating credits, or to throttle the client to use smaller amount of simultaneous i/o or to workaround server performance issues. Also adds a cap, so that even if the server granted us more than 65000 credits due to a server bug, we would not use that many. Signed-off-by: Steve French <steve.french@primarydata.com>
2016-10-12fs/cifs: reopen persistent handles on reconnectSteve French3-0/+25
Continuous Availability features like persistent handles require that clients reconnect their open files, not just the sessions, soon after the network connection comes back up, otherwise the server will throw away the state (byte range locks, leases, deny modes) on those handles after a timeout. Add code to reconnect handles when use_persistent set (e.g. Continuous Availability shares) after tree reconnect. Signed-off-by: Aurelien Aptel <aaptel@suse.com> Reviewed-by: Germano Percossi <germano.percossi@citrix.com> Signed-off-by: Steve French <smfrench@gmail.com>
2016-10-12Clarify locking of cifs file and tcon structures and make more granularSteve French7-63/+75
Remove the global file_list_lock to simplify cifs/smb3 locking and have spinlocks that more closely match the information they are protecting. Add new tcon->open_file_lock and file->file_info_lock spinlocks. Locks continue to follow a heirachy, cifs_socket --> cifs_ses --> cifs_tcon --> cifs_file where global tcp_ses_lock still protects socket and cifs_ses, while the the newer locks protect the lower level structure's information (tcon and cifs_file respectively). CC: Stable <stable@vger.kernel.org> Signed-off-by: Steve French <steve.french@primarydata.com> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Reviewed-by: Germano Percossi <germano.percossi@citrix.com>
2016-10-12Fix regression which breaks DFS mountingSachin Prabhu1-6/+8
Patch a6b5058 results in -EREMOTE returned by is_path_accessible() in cifs_mount() to be ignored which breaks DFS mounting. Signed-off-by: Sachin Prabhu <sprabhu@redhat.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com> CC: Stable <stable@vger.kernel.org> Signed-off-by: Steve French <smfrench@gmail.com>
2016-10-12fs/cifs: keep guid when assigning fid to fileinfoAurelien Aptel1-0/+1
When we open a durable handle we give a Globally Unique Identifier (GUID) to the server which we must keep for later reference e.g. when reopening persistent handles on reconnection. Without this the GUID generated for a new persistent handle was lost and 16 zero bytes were used instead on re-opening. Signed-off-by: Aurelien Aptel <aaptel@suse.com> CC: Stable <stable@vger.kernel.org> Signed-off-by: Steve French <smfrench@gmail.com>
2016-10-12SMB3: GUIDs should be constructed as random but valid uuidsSteve French4-4/+4
GUIDs although random, and 16 bytes, need to be generated as proper uuids. Signed-off-by: Steve French <steve.french@primarydata.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Reported-by: David Goebels <davidgoe@microsoft.com> CC: Stable <stable@vger.kernel.org>
2016-10-12Set previous session id correctly on SMB3 reconnectSteve French2-1/+6
Signed-off-by: Steve French <steve.french@primarydata.com> CC: Stable <stable@vger.kernel.org> Reported-by: David Goebel <davidgoe@microsoft.com>
2016-10-12cifs: Limit the overall credit acquiredRoss Lagerwall2-1/+27
The kernel client requests 2 credits for many operations even though they only use 1 credit (presumably to build up a buffer of credit). Some servers seem to give the client as much credit as is requested. In this case, the amount of credit the client has continues increasing to the point where (server->credits * MAX_BUFFER_SIZE) overflows in smb2_wait_mtu_credits(). Fix this by throttling the credit requests if an set limit is reached. For async requests where the credit charge may be > 1, request as much credit as what is charged. The limit is chosen somewhat arbitrarily. The Windows client defaults to 128 credits, the Windows server allows clients up to 512 credits (or 8192 for Windows 2016), and the NetApp server (and at least one other) does not limit clients at all. Choose a high enough value such that the client shouldn't limit performance. This behavior was seen with a NetApp filer (NetApp Release 9.0RC2). Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> CC: Stable <stable@vger.kernel.org> Signed-off-by: Steve French <smfrench@gmail.com>
2016-10-12Display number of credits availableSteve French1-0/+1
In debugging smb3, it is useful to display the number of credits available, so we can see when the server has not granted sufficient operations for the client to make progress, or alternatively the client has requested too many credits (as we saw in a recent bug) so we can compare with the number of credits the server thinks we have. Add a /proc/fs/cifs/DebugData line to display the client view on how many credits are available. Signed-off-by: Steve French <steve.french@primarydata.com> Reported-by: Germano Percossi <germano.percossi@citrix.com> CC: Stable <stable@vger.kernel.org>
2016-10-12Add way to query creation time of file via cifs xattrSteve French1-1/+27
Add parsing for new pseudo-xattr user.cifs.creationtime file attribute to allow backup and test applications to view birth time of file on cifs/smb3 mounts. Signed-off-by: Steve French <steve.french@primarydata.com>
2016-10-12Add way to query file attributes via cifs xattrSteve French1-1/+33
Add parsing for new pseudo-xattr user.cifs.dosattrib file attribute so tools can recognize what kind of file it is, and verify if common SMB3 attributes (system, hidden, archive, sparse, indexed etc.) are set. Signed-off-by: Steve French <steve.french@primarydata.com> Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
2016-10-12Btrfs: fix incremental send failure caused by balanceFilipe Manana1-0/+58
Commit 951555856b88 ("Btrfs: send, don't bug on inconsistent snapshots") removed some BUG_ON() statements (replacing them with returning errors to user space and logging error messages) when a snapshot is in an inconsistent state due to failures to update a delayed inode item (ENOMEM or ENOSPC) after adding/updating/deleting references, xattrs or file extent items. However there is a case, when no errors happen, where a file extent item can be modified without having the corresponding inode item updated. This case happens during balance under very specific timings, when relocation is in the stage where it updates data pointers and a leaf that contains file extent items is COWed. When that happens file extent items get their disk_bytenr field updated to a new value that reflects the post relocation logical address of the extent, without updating their respective inode items (as there is nothing that needs to be updated on them). This is performed at relocation.c:replace_file_extents() through relocation.c:btrfs_reloc_cow_block(). So make an incremental send deal with this case and don't do any processing for a file extent item that got its disk_bytenr field updated by relocation, since the extent's data is the same as the one pointed by the file extent item in the parent snapshot. After the recent commit mentioned above this case resulted in EIO errors returned to user space (and an error message logged to dmesg/syslog) when doing an incremental send, while before it, it resulted in hitting a BUG_ON leading to the following trace: [ 952.206705] ------------[ cut here ]------------ [ 952.206714] kernel BUG at ../fs/btrfs/send.c:5653! [ 952.206719] Internal error: Oops - BUG: 0 [#1] SMP [ 952.209854] Modules linked in: st dm_mod nls_utf8 isofs fuse nf_log_ipv6 xt_pkttype xt_physdev br_netfilter nf_log_ipv4 nf_log_common xt_LOG xt_limit ebtable_filter ebtables af_packet bridge stp llc ip6t_REJECT xt_tcpudp nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_raw ipt_REJECT iptable_raw xt_CT iptable_filter ip6table_mangle nf_conntrack_netbios_ns nf_conntrack_broadcast nf_conntrack_ipv4 nf_defrag_ipv4 ip_tables xt_conntrack nf_conntrack ip6table_filter ip6_tables x_tables xfs libcrc32c nls_iso8859_1 nls_cp437 vfat fat joydev aes_ce_blk ablk_helper cryptd snd_intel8x0 aes_ce_cipher snd_ac97_codec ac97_bus snd_pcm ghash_ce sha2_ce sha1_ce snd_timer snd virtio_net soundcore btrfs xor sr_mod cdrom hid_generic usbhid raid6_pq virtio_blk virtio_scsi bochs_drm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm virtio_mmio xhci_pci xhci_hcd usbcore usb_common virtio_pci virtio_ring virtio drm sg efivarfs [ 952.228333] Supported: Yes [ 952.228908] CPU: 0 PID: 12779 Comm: snapperd Not tainted 4.4.14-50-default #1 [ 952.230329] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 952.231683] task: ffff800058e94100 ti: ffff8000d866c000 task.ti: ffff8000d866c000 [ 952.233279] PC is at changed_cb+0x9f4/0xa48 [btrfs] [ 952.234375] LR is at changed_cb+0x58/0xa48 [btrfs] [ 952.236552] pc : [<ffff7ffffc39de7c>] lr : [<ffff7ffffc39d4e0>] pstate: 80000145 [ 952.238049] sp : ffff8000d866fa20 [ 952.238732] x29: ffff8000d866fa20 x28: 0000000000000019 [ 952.239840] x27: 00000000000028d5 x26: 00000000000024a2 [ 952.241008] x25: 0000000000000002 x24: ffff8000e66e92f0 [ 952.242131] x23: ffff8000b8c76800 x22: ffff800092879140 [ 952.243238] x21: 0000000000000002 x20: ffff8000d866fb78 [ 952.244348] x19: ffff8000b8f8c200 x18: 0000000000002710 [ 952.245607] x17: 0000ffff90d42480 x16: ffff800000237dc0 [ 952.246719] x15: 0000ffff90de7510 x14: ab000c000a2faf08 [ 952.247835] x13: 0000000000577c2b x12: ab000c000b696665 [ 952.248981] x11: 2e65726f632f6966 x10: 652d34366d72612f [ 952.250101] x9 : 32627572672f746f x8 : ab000c00092f1671 [ 952.251352] x7 : 8000000000577c2b x6 : ffff800053eadf45 [ 952.252468] x5 : 0000000000000000 x4 : ffff80005e169494 [ 952.253582] x3 : 0000000000000004 x2 : ffff8000d866fb78 [ 952.254695] x1 : 000000000003e2a3 x0 : 000000000003e2a4 [ 952.255803] [ 952.256150] Process snapperd (pid: 12779, stack limit = 0xffff8000d866c020) [ 952.257516] Stack: (0xffff8000d866fa20 to 0xffff8000d8670000) [ 952.258654] fa20: ffff8000d866fae0 ffff7ffffc308fc0 ffff800092879140 ffff8000e66e92f0 [ 952.260219] fa40: 0000000000000035 ffff800055de6000 ffff8000b8c76800 ffff8000d866fb78 [ 952.261745] fa60: 0000000000000002 00000000000024a2 00000000000028d5 0000000000000019 [ 952.263269] fa80: ffff8000d866fae0 ffff7ffffc3090f0 ffff8000d866fae0 ffff7ffffc309128 [ 952.264797] faa0: ffff800092879140 ffff8000e66e92f0 0000000000000035 ffff800055de6000 [ 952.268261] fac0: ffff8000b8c76800 ffff8000d866fb78 0000000000000002 0000000000001000 [ 952.269822] fae0: ffff8000d866fbc0 ffff7ffffc39ecfc ffff8000b8f8c200 ffff8000b8f8c368 [ 952.271368] fb00: ffff8000b8f8c378 ffff800055de6000 0000000000000001 ffff8000ecb17500 [ 952.272893] fb20: ffff8000b8c76800 ffff800092879140 ffff800062b6d000 ffff80007a9e2470 [ 952.274420] fb40: ffff8000b8f8c208 0000000005784000 ffff8000580a8000 ffff8000b8f8c200 [ 952.276088] fb60: ffff7ffffc39d488 00000002b8f8c368 0000000000000000 000000000003e2a4 [ 952.280275] fb80: 000000000000006c ffff7ffffc39ec00 000000000003e2a4 000000000000006c [ 952.283219] fba0: ffff8000b8f8c300 0000000000000100 0000000000000001 ffff8000ecb17500 [ 952.286166] fbc0: ffff8000d866fcd0 ffff7ffffc3643c0 ffff8000f8842700 0000ffff8ffe9278 [ 952.289136] fbe0: 0000000040489426 ffff800055de6000 0000ffff8ffe9278 0000000040489426 [ 952.292083] fc00: 000000000000011d 000000000000001d ffff80007a9e4598 ffff80007a9e43e8 [ 952.294959] fc20: ffff8000b8c7693f 0000000000003b24 0000000000000019 ffff8000b8f8c218 [ 952.301161] fc40: 00000001d866fc70 ffff8000b8c76800 0000000000000128 ffffffffffffff84 [ 952.305749] fc60: ffff800058e941ff 0000000000003a58 ffff8000d866fcb0 ffff8000000f7390 [ 952.308875] fc80: 000000000000012a 0000000000010290 ffff8000d866fc00 000000000000007b [ 952.311915] fca0: 0000000000010290 ffff800046c1b100 74732d7366727462 000001006d616572 [ 952.314937] fcc0: ffff8000fffc4100 cb88537fdc8ba60e ffff8000d866fe10 ffff8000002499e8 [ 952.318008] fce0: 0000000040489426 ffff8000f8842700 0000ffff8ffe9278 ffff80007a9e4598 [ 952.321321] fd00: 0000ffff8ffe9278 0000000040489426 000000000000011d 000000000000001d [ 952.324280] fd20: ffff80000072c000 ffff8000d866c000 ffff8000d866fda0 ffff8000000e997c [ 952.327156] fd40: ffff8000fffc4180 00000000000031ed ffff8000fffc4180 ffff800046c1b7d4 [ 952.329895] fd60: 0000000000000140 0000ffff907ea170 000000000000011d 00000000000000dc [ 952.334641] fd80: ffff80000072c000 ffff8000d866c000 0000000000000000 0000000000000002 [ 952.338002] fda0: ffff8000d866fdd0 ffff8000000ebacc ffff800046c1b080 ffff800046c1b7d4 [ 952.340724] fdc0: ffff8000d866fdf0 ffff8000000db67c 0000000000000040 ffff800000e69198 [ 952.343415] fde0: 0000ffff8ffea790 00000000000031ed ffff8000d866fe20 ffff800000254000 [ 952.346101] fe00: 000000000000001d 0000000000000004 ffff8000d866fe90 ffff800000249d3c [ 952.348980] fe20: ffff8000f8842700 0000000000000000 ffff8000f8842701 0000000000000008 [ 952.351696] fe40: ffff8000d866fe70 0000000000000008 ffff8000d866fe90 ffff800000249cf8 [ 952.354387] fe60: ffff8000f8842700 0000ffff8ffe9170 ffff8000f8842701 0000000000000008 [ 952.357083] fe80: 0000ffff8ffe9278 ffff80008ff85500 0000ffff8ffe90c0 ffff800000085c84 [ 952.359800] fea0: 0000000000000000 0000ffff8ffe9170 ffffffffffffffff 0000ffff90d473bc [ 952.365351] fec0: 0000000000000000 0000000000000015 0000000000000008 0000000040489426 [ 952.369550] fee0: 0000ffff8ffe9278 0000ffff907ea790 0000ffff907ea170 0000ffff907ea790 [ 952.372416] ff00: 0000ffff907ea170 0000000000000000 000000000000001d 0000000000000004 [ 952.375223] ff20: 0000ffff90a32220 00000000003d0f00 0000ffff907ea0a0 0000ffff8ffe8f30 [ 952.378099] ff40: 0000ffff9100f554 0000ffff91147000 0000ffff91117bc0 0000ffff90d473b0 [ 952.381115] ff60: 0000ffff9100f620 0000ffff880069b0 0000ffff8ffe9170 0000ffff8ffe91a0 [ 952.384003] ff80: 0000ffff8ffe9160 0000ffff8ffe9140 0000ffff88006990 0000ffff8ffe9278 [ 952.386860] ffa0: 0000ffff88008a60 0000ffff8ffe9480 0000ffff88014ca0 0000ffff8ffe90c0 [ 952.389654] ffc0: 0000ffff910be8e8 0000ffff8ffe90c0 0000ffff90d473bc 0000000000000000 [ 952.410986] ffe0: 0000000000000008 000000000000001d 6e2079747265706f 72616d223d656d61 [ 952.415497] Call trace: [ 952.417403] [<ffff7ffffc39de7c>] changed_cb+0x9f4/0xa48 [btrfs] [ 952.420023] [<ffff7ffffc308fc0>] btrfs_compare_trees+0x500/0x6b0 [btrfs] [ 952.422759] [<ffff7ffffc39ecfc>] btrfs_ioctl_send+0xb4c/0xe10 [btrfs] [ 952.425601] [<ffff7ffffc3643c0>] btrfs_ioctl+0x374/0x29a4 [btrfs] [ 952.428031] [<ffff8000002499e8>] do_vfs_ioctl+0x33c/0x600 [ 952.430360] [<ffff800000249d3c>] SyS_ioctl+0x90/0xa4 [ 952.432552] [<ffff800000085c84>] el0_svc_naked+0x38/0x3c [ 952.434803] Code: 2a1503e0 17fffdac b9404282 17ffff28 (d4210000) [ 952.437457] ---[ end trace 9afd7090c466cf15 ]--- Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-10-11Merge branch 'akpm' (patches from Andrew)Linus Torvalds16-159/+259
Merge more updates from Andrew Morton: - a few block updates that fell in my lap - lib/ updates - checkpatch - autofs - ipc - a ton of misc other things * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (100 commits) mm: split gfp_mask and mapping flags into separate fields fs: use mapping_set_error instead of opencoded set_bit treewide: remove redundant #include <linux/kconfig.h> hung_task: allow hung_task_panic when hung_task_warnings is 0 kthread: add kerneldoc for kthread_create() kthread: better support freezable kthread workers kthread: allow to modify delayed kthread work kthread: allow to cancel kthread work kthread: initial support for delayed kthread work kthread: detect when a kthread work is used by more workers kthread: add kthread_destroy_worker() kthread: add kthread_create_worker*() kthread: allow to call __kthread_create_on_node() with va_list args kthread/smpboot: do not park in kthread_create_on_cpu() kthread: kthread worker API cleanup kthread: rename probe_kthread_data() to kthread_probe_data() scripts/tags.sh: enable code completion in VIM mm: kmemleak: avoid using __va() on addresses that don't have a lowmem mapping kdump, vmcoreinfo: report memory sections virtual addresses ipc/sem.c: add cond_resched in exit_sme ...
2016-10-11fs: use mapping_set_error instead of opencoded set_bitMichal Hocko6-10/+8
The mapping_set_error() helper sets the correct AS_ flag for the mapping so there is no reason to open code it. Use the helper directly. [akpm@linux-foundation.org: be honest about conversion from -ENXIO to -EIO] Link: http://lkml.kernel.org/r/20160912111608.2588-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11treewide: remove redundant #include <linux/kconfig.h>Masahiro Yamada1-2/+0
Kernel source files need not include <linux/kconfig.h> explicitly because the top Makefile forces to include it with: -include $(srctree)/include/linux/kconfig.h This commit removes explicit includes except the following: * arch/s390/include/asm/facilities_src.h * tools/testing/radix-tree/linux/kernel.h These two are used for host programs. Link: http://lkml.kernel.org/r/1473656164-11929-1-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11pipe: cap initial pipe capacity according to pipe-max-size limitMichael Kerrisk (man-pages)1-0/+3
This is a patch that provides behavior that is more consistent, and probably less surprising to users. I consider the change optional, and welcome opinions about whether it should be applied. By default, pipes are created with a capacity of 64 kiB. However, /proc/sys/fs/pipe-max-size may be set smaller than this value. In this scenario, an unprivileged user could thus create a pipe whose initial capacity exceeds the limit. Therefore, it seems logical to cap the initial pipe capacity according to the value of pipe-max-size. The test program shown earlier in this patch series can be used to demonstrate the effect of the change brought about with this patch: # cat /proc/sys/fs/pipe-max-size 1048576 # sudo -u mtk ./test_F_SETPIPE_SZ 1 Initial pipe capacity: 65536 # echo 10000 > /proc/sys/fs/pipe-max-size # cat /proc/sys/fs/pipe-max-size 16384 # sudo -u mtk ./test_F_SETPIPE_SZ 1 Initial pipe capacity: 16384 # ./test_F_SETPIPE_SZ 1 Initial pipe capacity: 65536 The last two executions of 'test_F_SETPIPE_SZ' show that pipe-max-size caps the initial allocation for a new pipe for unprivileged users, but not for privileged users. Link: http://lkml.kernel.org/r/31dc7064-2a17-9c5b-1df1-4e3012ee992c@gmail.com Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Willy Tarreau <w@1wt.eu> Cc: <socketpair@gmail.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Jens Axboe <axboe@fb.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11pipe: make account_pipe_buffers() return a value, and use itMichael Kerrisk (man-pages)1-18/+18
This is an optional patch, to provide a small performance improvement. Alter account_pipe_buffers() so that it returns the new value in user->pipe_bufs. This means that we can refactor too_many_pipe_buffers_soft() and too_many_pipe_buffers_hard() to avoid the costs of repeated use of atomic_long_read() to get the value user->pipe_bufs. Link: http://lkml.kernel.org/r/93e5f193-1e5e-3e1f-3a20-eae79b7e1310@gmail.com Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Willy Tarreau <w@1wt.eu> Cc: <socketpair@gmail.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Jens Axboe <axboe@fb.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11pipe: fix limit checking in alloc_pipe_info()Michael Kerrisk (man-pages)1-7/+13
The limit checking in alloc_pipe_info() (used by pipe(2) and when opening a FIFO) has the following problems: (1) When checking capacity required for the new pipe, the checks against the limit in /proc/sys/fs/pipe-user-pages-{soft,hard} are made against existing consumption, and exclude the memory required for the new pipe capacity. As a consequence: (1) the memory allocation throttling provided by the soft limit does not kick in quite as early as it should, and (2) the user can overrun the hard limit. (2) As currently implemented, accounting and checking against the limits is done as follows: (a) Test whether the user has exceeded the limit. (b) Make new pipe buffer allocation. (c) Account new allocation against the limits. This is racey. Multiple processes may pass point (a) simultaneously, and then allocate pipe buffers that are accounted for only in step (c). The race means that the user's pipe buffer allocation could be pushed over the limit (by an arbitrary amount, depending on how unlucky we were in the race). [Thanks to Vegard Nossum for spotting this point, which I had missed.] This patch addresses the above problems as follows: * Alter the checks against limits to include the memory required for the new pipe. * Re-order the accounting step so that it precedes the buffer allocation. If the accounting step determines that a limit has been reached, revert the accounting and cause the operation to fail. Link: http://lkml.kernel.org/r/8ff3e9f9-23f6-510c-644f-8e70cd1c0bd9@gmail.com Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Willy Tarreau <w@1wt.eu> Cc: <socketpair@gmail.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Jens Axboe <axboe@fb.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11pipe: simplify logic in alloc_pipe_info()Michael Kerrisk (man-pages)1-22/+23
Replace an 'if' block that covers most of the code in this function with a 'goto'. This makes the code a little simpler to read, and also simplifies the next patch (fix limit checking in alloc_pipe_info()) Link: http://lkml.kernel.org/r/aef030c1-0257-98a9-4988-186efa48530c@gmail.com Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Willy Tarreau <w@1wt.eu> Cc: <socketpair@gmail.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Jens Axboe <axboe@fb.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11pipe: fix limit checking in pipe_set_size()Michael Kerrisk (man-pages)1-10/+31
The limit checking in pipe_set_size() (used by fcntl(F_SETPIPE_SZ)) has the following problems: (1) When increasing the pipe capacity, the checks against the limits in /proc/sys/fs/pipe-user-pages-{soft,hard} are made against existing consumption, and exclude the memory required for the increased pipe capacity. The new increase in pipe capacity can then push the total memory used by the user for pipes (possibly far) over a limit. This can also trigger the problem described next. (2) The limit checks are performed even when the new pipe capacity is less than the existing pipe capacity. This can lead to problems if a user sets a large pipe capacity, and then the limits are lowered, with the result that the user will no longer be able to decrease the pipe capacity. (3) As currently implemented, accounting and checking against the limits is done as follows: (a) Test whether the user has exceeded the limit. (b) Make new pipe buffer allocation. (c) Account new allocation against the limits. This is racey. Multiple processes may pass point (a) simultaneously, and then allocate pipe buffers that are accounted for only in step (c). The race means that the user's pipe buffer allocation could be pushed over the limit (by an arbitrary amount, depending on how unlucky we were in the race). [Thanks to Vegard Nossum for spotting this point, which I had missed.] This patch addresses the above problems as follows: * Perform checks against the limits only when increasing a pipe's capacity; an unprivileged user can always decrease a pipe's capacity. * Alter the checks against limits to include the memory required for the new pipe capacity. * Re-order the accounting step so that it precedes the buffer allocation. If the accounting step determines that a limit has been reached, revert the accounting and cause the operation to fail. The program below can be used to demonstrate problems 1 and 2, and the effect of the fix. The program takes one or more command-line arguments. The first argument specifies the number of pipes that the program should create. The remaining arguments are, alternately, pipe capacities that should be set using fcntl(F_SETPIPE_SZ), and sleep intervals (in seconds) between the fcntl() operations. (The sleep intervals allow the possibility to change the limits between fcntl() operations.) Problem 1 ========= Using the test program on an unpatched kernel, we first set some limits: # echo 0 > /proc/sys/fs/pipe-user-pages-soft # echo 1000000000 > /proc/sys/fs/pipe-max-size # echo 10000 > /proc/sys/fs/pipe-user-pages-hard # 40.96 MB Then show that we can set a pipe with capacity (100MB) that is over the hard limit # sudo -u mtk ./test_F_SETPIPE_SZ 1 100000000 Initial pipe capacity: 65536 Loop 1: set pipe capacity to 100000000 bytes F_SETPIPE_SZ returned 134217728 Now set the capacity to 100MB twice. The second call fails (which is probably surprising to most users, since it seems like a no-op): # sudo -u mtk ./test_F_SETPIPE_SZ 1 100000000 0 100000000 Initial pipe capacity: 65536 Loop 1: set pipe capacity to 100000000 bytes F_SETPIPE_SZ returned 134217728 Loop 2: set pipe capacity to 100000000 bytes Loop 2, pipe 0: F_SETPIPE_SZ failed: fcntl: Operation not permitted With a patched kernel, setting a capacity over the limit fails at the first attempt: # echo 0 > /proc/sys/fs/pipe-user-pages-soft # echo 1000000000 > /proc/sys/fs/pipe-max-size # echo 10000 > /proc/sys/fs/pipe-user-pages-hard # sudo -u mtk ./test_F_SETPIPE_SZ 1 100000000 Initial pipe capacity: 65536 Loop 1: set pipe capacity to 100000000 bytes Loop 1, pipe 0: F_SETPIPE_SZ failed: fcntl: Operation not permitted There is a small chance that the change to fix this problem could break user-space, since there are cases where fcntl(F_SETPIPE_SZ) calls that previously succeeded might fail. However, the chances are small, since (a) the pipe-user-pages-{soft,hard} limits are new (in 4.5), and the default soft/hard limits are high/unlimited. Therefore, it seems warranted to make these limits operate more precisely (and behave more like what users probably expect). Problem 2 ========= Running the test program on an unpatched kernel, we first set some limits: # getconf PAGESIZE 4096 # echo 0 > /proc/sys/fs/pipe-user-pages-soft # echo 1000000000 > /proc/sys/fs/pipe-max-size # echo 10000 > /proc/sys/fs/pipe-user-pages-hard # 40.96 MB Now perform two fcntl(F_SETPIPE_SZ) operations on a single pipe, first setting a pipe capacity (10MB), sleeping for a few seconds, during which time the hard limit is lowered, and then set pipe capacity to a smaller amount (5MB): # sudo -u mtk ./test_F_SETPIPE_SZ 1 10000000 15 5000000 & [1] 748 # Initial pipe capacity: 65536 Loop 1: set pipe capacity to 10000000 bytes F_SETPIPE_SZ returned 16777216 Sleeping 15 seconds # echo 1000 > /proc/sys/fs/pipe-user-pages-hard # 4.096 MB # Loop 2: set pipe capacity to 5000000 bytes Loop 2, pipe 0: F_SETPIPE_SZ failed: fcntl: Operation not permitted In this case, the user should be able to lower the limit. With a kernel that has the patch below, the second fcntl() succeeds: # echo 0 > /proc/sys/fs/pipe-user-pages-soft # echo 1000000000 > /proc/sys/fs/pipe-max-size # echo 10000 > /proc/sys/fs/pipe-user-pages-hard # sudo -u mtk ./test_F_SETPIPE_SZ 1 10000000 15 5000000 & [1] 3215 # Initial pipe capacity: 65536 # Loop 1: set pipe capacity to 10000000 bytes F_SETPIPE_SZ returned 16777216 Sleeping 15 seconds # echo 1000 > /proc/sys/fs/pipe-user-pages-hard # Loop 2: set pipe capacity to 5000000 bytes F_SETPIPE_SZ returned 8388608 8x---8x---8x---8x---8x---8x---8x---8x---8x---8x---8x---8x---8x---8x--- /* test_F_SETPIPE_SZ.c (C) 2016, Michael Kerrisk; licensed under GNU GPL version 2 or later Test operation of fcntl(F_SETPIPE_SZ) for setting pipe capacity and interactions with limits defined by /proc/sys/fs/pipe-* files. */ #define _GNU_SOURCE #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <unistd.h> int main(int argc, char *argv[]) { int (*pfd)[2]; int npipes; int pcap, rcap; int j, p, s, stime, loop; if (argc < 2) { fprintf(stderr, "Usage: %s num-pipes " "[pipe-capacity sleep-time]...\n", argv[0]); exit(EXIT_FAILURE); } npipes = atoi(argv[1]); pfd = calloc(npipes, sizeof (int [2])); if (pfd == NULL) { perror("calloc"); exit(EXIT_FAILURE); } for (j = 0; j < npipes; j++) { if (pipe(pfd[j]) == -1) { fprintf(stderr, "Loop %d: pipe() failed: ", j); perror("pipe"); exit(EXIT_FAILURE); } } printf("Initial pipe capacity: %d\n", fcntl(pfd[0][0], F_GETPIPE_SZ)); for (j = 2; j < argc; j += 2 ) { loop = j / 2; pcap = atoi(argv[j]); printf(" Loop %d: set pipe capacity to %d bytes\n", loop, pcap); for (p = 0; p < npipes; p++) { s = fcntl(pfd[p][0], F_SETPIPE_SZ, pcap); if (s == -1) { fprintf(stderr, " Loop %d, pipe %d: F_SETPIPE_SZ " "failed: ", loop, p); perror("fcntl"); exit(EXIT_FAILURE); } if (p == 0) { printf(" F_SETPIPE_SZ returned %d\n", s); rcap = s; } else { if (s != rcap) { fprintf(stderr, " Loop %d, pipe %d: F_SETPIPE_SZ " "unexpected return: %d\n", loop, p, s); exit(EXIT_FAILURE); } } stime = (j + 1 < argc) ? atoi(argv[j + 1]) : 0; if (stime > 0) { printf(" Sleeping %d seconds\n", stime); sleep(stime); } } } exit(EXIT_SUCCESS); } 8x---8x---8x---8x---8x---8x---8x---8x---8x---8x---8x---8x---8x---8x--- Patch history: v2 * Switch order of test in 'if' statement to avoid function call (to capability()) in normal path. [This is a fix to a preexisting wart in the code. Thanks to Willy Tarreau] * Perform (size > pipe_max_size) check before calling account_pipe_buffers(). [Thanks to Vegard Nossum] Quoting Vegard: The potential problem happens if the user passes a very large number which will overflow pipe->user->pipe_bufs. On 32-bit, sizeof(int) == sizeof(long), so if they pass arg = INT_MAX then round_pipe_size() returns INT_MAX. Although it's true that the accounting is done in terms of pages and not bytes, so you'd need on the order of (1 << 13) = 8192 processes hitting the limit at the same time in order to make it overflow, which seems a bit unlikely. (See https://lkml.org/lkml/2016/8/12/215 for another discussion on the limit checking) Link: http://lkml.kernel.org/r/1e464945-536b-2420-798b-e77b9c7e8593@gmail.com Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Willy Tarreau <w@1wt.eu> Cc: <socketpair@gmail.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Jens Axboe <axboe@fb.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11pipe: refactor argument for account_pipe_buffers()Michael Kerrisk (man-pages)1-5/+5
This is a preparatory patch for following work. account_pipe_buffers() performs accounting in the 'user_struct'. There is no need to pass a pointer to a 'pipe_inode_info' struct (which is then dereferenced to obtain a pointer to the 'user' field). Instead, pass a pointer directly to the 'user_struct'. This change is needed in preparation for a subsequent patch that the fixes the limit checking in alloc_pipe_info() (and the resulting code is a little more logical). Link: http://lkml.kernel.org/r/7277bf8c-a6fc-4a7d-659c-f5b145c981ab@gmail.com Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Willy Tarreau <w@1wt.eu> Cc: <socketpair@gmail.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Jens Axboe <axboe@fb.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11pipe: move limit checking logic into pipe_set_size()Michael Kerrisk (man-pages)1-23/+18
This is a preparatory patch for following work. Move the F_SETPIPE_SZ limit-checking logic from pipe_fcntl() into pipe_set_size(). This simplifies the code a little, and allows for reworking required in a later patch that fixes the limit checking in pipe_set_size() Link: http://lkml.kernel.org/r/3701b2c5-2c52-2c3e-226d-29b9deb29b50@gmail.com Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Willy Tarreau <w@1wt.eu> Cc: <socketpair@gmail.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Jens Axboe <axboe@fb.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11pipe: relocate round_pipe_size() above pipe_set_size()Michael Kerrisk (man-pages)1-12/+12
Patch series "pipe: fix limit handling", v2. When changing a pipe's capacity with fcntl(F_SETPIPE_SZ), various limits defined by /proc/sys/fs/pipe-* files are checked to see if unprivileged users are exceeding limits on memory consumption. While documenting and testing the operation of these limits I noticed that, as currently implemented, these checks have a number of problems: (1) When increasing the pipe capacity, the checks against the limits in /proc/sys/fs/pipe-user-pages-{soft,hard} are made against existing consumption, and exclude the memory required for the increased pipe capacity. The new increase in pipe capacity can then push the total memory used by the user for pipes (possibly far) over a limit. This can also trigger the problem described next. (2) The limit checks are performed even when the new pipe capacity is less than the existing pipe capacity. This can lead to problems if a user sets a large pipe capacity, and then the limits are lowered, with the result that the user will no longer be able to decrease the pipe capacity. (3) As currently implemented, accounting and checking against the limits is done as follows: (a) Test whether the user has exceeded the limit. (b) Make new pipe buffer allocation. (c) Account new allocation against the limits. This is racey. Multiple processes may pass point (a) simultaneously, and then allocate pipe buffers that are accounted for only in step (c). The race means that the user's pipe buffer allocation could be pushed over the limit (by an arbitrary amount, depending on how unlucky we were in the race). [Thanks to Vegard Nossum for spotting this point, which I had missed.] This patch series addresses these three problems. This patch (of 8): This is a minor preparatory patch. After subsequent patches, round_pipe_size() will be called from pipe_set_size(), so place round_pipe_size() above pipe_set_size(). Link: http://lkml.kernel.org/r/91a91fdb-a959-ba7f-b551-b62477cc98a1@gmail.com Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Willy Tarreau <w@1wt.eu> Cc: <socketpair@gmail.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Jens Axboe <axboe@fb.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11autofs: refactor ioctl fn vector in iookup_dev_ioctl()Tomohiro Kusumi1-33/+16
cmd part of this struct is the same as an index of itself within _ioctls[]. In fact this cmd is unused, so we can drop this part. Link: http://lkml.kernel.org/r/20160831033414.9910.66697.stgit@pluto.themaw.net Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com> Signed-off-by: Ian Kent <raven@themaw.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11autofs: remove possibly misleading /* #define DEBUG */Tomohiro Kusumi1-2/+0
Having this in autofs_i.h gives illusion that uncommenting this enables pr_debug(), but it doesn't enable all the pr_debug() in autofs because inclusion order matters. XFS has the same DEBUG macro in its core header fs/xfs/xfs.h, however XFS seems to have a rule to include this prior to other XFS headers as well as kernel headers. This is not the case with autofs, and DEBUG could be enabled via Makefile, so autofs should just get rid of this comment to make the code less confusing. It's a comment, so there is literally no functional difference. Link: http://lkml.kernel.org/r/20160831033409.9910.77067.stgit@pluto.themaw.net Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com> Signed-off-by: Ian Kent <raven@themaw.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11autofs: fix print format for ioctl warning messageTomohiro Kusumi1-1/+1
All other warnings use "cmd(0x%08x)" and this is the only one with "cmd(%d)". (below comes from my userspace debug program, but not automount daemon) [ 1139.905676] autofs4:pid:1640:check_dev_ioctl_version: ioctl control interface version mismatch: kernel(1.0), user(0.0), cmd(-1072131215) Link: http://lkml.kernel.org/r/20160812024851.12352.75458.stgit@pluto.themaw.net Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com> Signed-off-by: Ian Kent <ikent@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11autofs: add autofs_dev_ioctl_version() for AUTOFS_DEV_IOCTL_VERSION_CMDIan Kent1-8/+17
No functional changes, based on the following justification. 1. Make the code more consistent using the ioctl vector _ioctls[], rather than assigning NULL only for this ioctl command. 2. Remove goto done; for better maintainability in the long run. 3. The existing code is based on the fact that validate_dev_ioctl() sets ioctl version for any command, but AUTOFS_DEV_IOCTL_VERSION_CMD should explicitly set it regardless of the default behavior. Link: http://lkml.kernel.org/r/20160812024846.12352.9885.stgit@pluto.themaw.net Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com> Signed-off-by: Ian Kent <ikent@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11autofs: fix dev ioctl number range checkIan Kent2-2/+3
The count of miscellaneous device ioctls in fs/autofs4/autofs_i.h is wrong. The number of ioctls is the difference between AUTOFS_DEV_IOCTL_VERSION_CMD and AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD (14) not the difference between AUTOFS_IOC_COUNT and 11 (21). [kusumi.tomohiro@gmail.com: fix typo that made the count macro negative] Link: http://lkml.kernel.org/r/20160831033420.9910.16809.stgit@pluto.themaw.net Link: http://lkml.kernel.org/r/20160812024841.12352.11975.stgit@pluto.themaw.net Signed-off-by: Ian Kent <raven@themaw.net> Cc: Tomohiro Kusumi <kusumi.tomohiro@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>