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2020-07-06xfs: mark inode buffers in cacheDave Chinner
Inode buffers always have write IO callbacks, so by marking them directly we can avoid needing to attach ->b_iodone functions to them. This avoids an indirect call, and makes future modifications much simpler. While this is largely a refactor of existing functionality, we broaden the scope of the flag to beyond where inodes are explicitly attached because future changes need to know what type of log items are attached to the buffer. Adding this buffer flag may invoke the inode iodone callback in cases where it wouldn't have been previously, but this is not a functional change because the callback is identical to the normal buffer write iodone callback when inodes are not attached. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-06xfs: add an inode item lockDave Chinner
The inode log item is kind of special in that it can be aggregating new changes in memory at the same time time existing changes are being written back to disk. This means there are fields in the log item that are accessed concurrently from contexts that don't share any locking at all. e.g. updating ili_last_fields occurs at flush time under the ILOCK_EXCL and flush lock at flush time, under the flush lock at IO completion time, and is read under the ILOCK_EXCL when the inode is logged. Hence there is no actual serialisation between reading the field during logging of the inode in transactions vs clearing the field in IO completion. We currently get away with this by the fact that we are only clearing fields in IO completion, and nothing bad happens if we accidentally log more of the inode than we actually modify. Worst case is we consume a tiny bit more memory and log bandwidth. However, if we want to do more complex state manipulations on the log item that requires updates at all three of these potential locations, we need to have some mechanism of serialising those operations. To do this, introduce a spinlock into the log item to serialise internal state. This could be done via the xfs_inode i_flags_lock, but this then leads to potential lock inversion issues where inode flag updates need to occur inside locks that best nest inside the inode log item locks (e.g. marking inodes stale during inode cluster freeing). Using a separate spinlock avoids these sorts of problems and simplifies future code. This does not touch the use of ili_fields in the item formatting code - that is entirely protected by the ILOCK_EXCL at this point in time, so it remains untouched. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-06xfs: remove logged flag from inode log itemDave Chinner
This was used to track if the item had logged fields being flushed to disk. We log everything in the inode these days, so this logic is no longer needed. Remove it. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-06xfs: Don't allow logging of XFS_ISTALE inodesDave Chinner
In tracking down a problem in this patchset, I discovered we are reclaiming dirty stale inodes. This wasn't discovered until inodes were always attached to the cluster buffer and then the rcu callback that freed inodes was assert failing because the inode still had an active pointer to the cluster buffer after it had been reclaimed. Debugging the issue indicated that this was a pre-existing issue resulting from the way the inodes are handled in xfs_inactive_ifree. When we free a cluster buffer from xfs_ifree_cluster, all the inodes in cache are marked XFS_ISTALE. Those that are clean have nothing else done to them and so eventually get cleaned up by background reclaim. i.e. it is assumed we'll never dirty/relog an inode marked XFS_ISTALE. On journal commit dirty stale inodes as are handled by both buffer and inode log items to run though xfs_istale_done() and removed from the AIL (buffer log item commit) or the log item will simply unpin it because the buffer log item will clean it. What happens to any specific inode is entirely dependent on which log item wins the commit race, but the result is the same - stale inodes are clean, not attached to the cluster buffer, and not in the AIL. Hence inode reclaim can just free these inodes without further care. However, if the stale inode is relogged, it gets dirtied again and relogged into the CIL. Most of the time this isn't an issue, because relogging simply changes the inode's location in the current checkpoint. Problems arise, however, when the CIL checkpoints between two transactions in the xfs_inactive_ifree() deferops processing. This results in the XFS_ISTALE inode being redirtied and inserted into the CIL without any of the other stale cluster buffer infrastructure being in place. Hence on journal commit, it simply gets unpinned, so it remains dirty in memory. Everything in inode writeback avoids XFS_ISTALE inodes so it can't be written back, and it is not tracked in the AIL so there's not even a trigger to attempt to clean the inode. Hence the inode just sits dirty in memory until inode reclaim comes along, sees that it is XFS_ISTALE, and goes to reclaim it. This reclaiming of a dirty inode caused use after free, list corruptions and other nasty issues later in this patchset. Hence this patch addresses a violation of the "never log XFS_ISTALE inodes" caused by the deferops processing rolling a transaction and relogging a stale inode in xfs_inactive_free. It also adds a bunch of asserts to catch this problem in debug kernels so that we don't reintroduce this problem in future. Reproducer for this issue was generic/558 on a v4 filesystem. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-06xfs: remove useless definitions in xfs_linux.hYafang Shao
Remove current_pid(), current_test_flags() and current_clear_flags_nested(), because they are useless. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-06xfs: use MMAPLOCK around filemap_map_pages()Dave Chinner
The page faultround path ->map_pages is implemented in XFS via filemap_map_pages(). This function checks that pages found in page cache lookups have not raced with truncate based invalidation by checking page->mapping is correct and page->index is within EOF. However, we've known for a long time that this is not sufficient to protect against races with invalidations done by operations that do not change EOF. e.g. hole punching and other fallocate() based direct extent manipulations. The way we protect against these races is we wrap the page fault operations in a XFS_MMAPLOCK_SHARED lock so they serialise against fallocate and truncate before calling into the filemap function that processes the fault. Do the same for XFS's ->map_pages implementation to close this potential data corruption issue. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-06xfs: move helpers that lock and unlock two inodes against userspace IODarrick J. Wong
Move the double-inode locking helpers to xfs_inode.c since they're not specific to reflink. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-07-06xfs: refactor locking and unlocking two inodes against userspace IODarrick J. Wong
Refactor the two functions that we use to lock and unlock two inodes to block userspace from initiating IO against a file, whether via system calls or mmap activity. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-07-06xfs: fix xfs_reflink_remap_prep calling conventionsDarrick J. Wong
Fix the return value of xfs_reflink_remap_prep so that its return value conventions match the rest of xfs. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-07-06xfs: reflink can skip remap existing mappingsDarrick J. Wong
If the source and destination map are identical, we can skip the remap step to save some time. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-07-06xfs: only reserve quota blocks if we're mapping into a holeDarrick J. Wong
When logging quota block count updates during a reflink operation, we only log the /delta/ of the block count changes to the dquot. Since we now know ahead of time the extent type of both dmap and smap (and that they have the same length), we know that we only need to reserve quota blocks for dmap's blockcount if we're mapping it into a hole. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-07-06xfs: only reserve quota blocks for bmbt changes if we're changing the data forkDarrick J. Wong
Now that we've reworked xfs_reflink_remap_extent to remap only one extent per transaction, we actually know if the extent being removed is an allocated mapping. This means that we now know ahead of time if we're going to be touching the data fork. Since we only need blocks for a bmbt split if we're going to update the data fork, we only need to get quota reservation if we know we're going to touch the data fork. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-07-06xfs: redesign the reflink remap loop to fix blkres depletion crashDarrick J. Wong
The existing reflink remapping loop has some structural problems that need addressing: The biggest problem is that we create one transaction for each extent in the source file without accounting for the number of mappings there are for the same range in the destination file. In other words, we don't know the number of remap operations that will be necessary and we therefore cannot guess the block reservation required. On highly fragmented filesystems (e.g. ones with active dedupe) we guess wrong, run out of block reservation, and fail. The second problem is that we don't actually use the bmap intents to their full potential -- instead of calling bunmapi directly and having to deal with its backwards operation, we could call the deferred ops xfs_bmap_unmap_extent and xfs_refcount_decrease_extent instead. This makes the frontend loop much simpler. Solve all of these problems by refactoring the remapping loops so that we only perform one remapping operation per transaction, and each operation only tries to remap a single extent from source to dest. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reported-by: Edwin Török <edwin@etorok.net> Tested-by: Edwin Török <edwin@etorok.net>
2020-07-06xfs: rename xfs_bmap_is_real_extent to is_written_extentDarrick J. Wong
The name of this predicate is a little misleading -- it decides if the extent mapping is allocated and written. Change the name to be more direct, as we're going to add a new predicate in the next patch. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-07-06xfs: fix reflink quota reservation accounting errorDarrick J. Wong
Quota reservations are supposed to account for the blocks that might be allocated due to a bmap btree split. Reflink doesn't do this, so fix this to make the quota accounting more accurate before we start rearranging things. Fixes: 862bb360ef56 ("xfs: reflink extents from one file to another") Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-07-06xfs: don't eat an EIO/ENOSPC writeback error when scrubbing data forkDarrick J. Wong
The data fork scrubber calls filemap_write_and_wait to flush dirty pages and delalloc reservations out to disk prior to checking the data fork's extent mappings. Unfortunately, this means that scrub can consume the EIO/ENOSPC errors that would otherwise have stayed around in the address space until (we hope) the writer application calls fsync to persist data and collect errors. The end result is that programs that wrote to a file might never see the error code and proceed as if nothing were wrong. xfs_scrub is not in a position to notify file writers about the writeback failure, and it's only here to check metadata, not file contents. Therefore, if writeback fails, we should stuff the error code back into the address space so that an fsync by the writer application can pick that up. Fixes: 99d9d8d05da2 ("xfs: scrub inode block mappings") Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-07-06xfs: preserve rmapbt swapext block reservation from freed blocksBrian Foster
The rmapbt extent swap algorithm remaps individual extents between the source inode and the target to trigger reverse mapping metadata updates. If either inode straddles a format or other bmap allocation boundary, the individual unmap and map cycles can trigger repeated bmap block allocations and frees as the extent count bounces back and forth across the boundary. While net block usage is bound across the swap operation, this behavior can prematurely exhaust the transaction block reservation because it continuously drains as the transaction rolls. Each allocation accounts against the reservation and each free returns to global free space on transaction roll. The previous workaround to this problem attempted to detect this boundary condition and provide surplus block reservation to acommodate it. This is insufficient because more remaps can occur than implied by the extent counts; if start offset boundaries are not aligned between the two inodes, for example. To address this problem more generically and dynamically, add a transaction accounting mode that returns freed blocks to the transaction reservation instead of the superblock counters on transaction roll and use it when the rmapbt based algorithm is active. This allows the chain of remap transactions to preserve the block reservation based own its own frees and prevent premature exhaustion regardless of the remap pattern. Note that this is only safe for superblocks with lazy sb accounting, but the latter is required for v5 supers and the rmap feature depends on v5. Fixes: b3fed434822d0 ("xfs: account format bouncing into rmapbt swapext tx reservation") Root-caused-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-06xfs: Couple of typo fixes in commentsKeyur Patel
./xfs/libxfs/xfs_inode_buf.c:56: unnecssary ==> unnecessary ./xfs/libxfs/xfs_inode_buf.c:59: behavour ==> behaviour ./xfs/libxfs/xfs_inode_buf.c:206: unitialized ==> uninitialized Signed-off-by: Keyur Patel <iamkeyur96@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-07-06io_uring: briefly loose locks while reaping eventsPavel Begunkov
It's not nice to hold @uring_lock for too long io_iopoll_reap_events(). For instance, the lock is needed to publish requests to @poll_list, and that locks out tasks doing that for no good reason. Loose it occasionally. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-06io_uring: fix stopping iopoll'ing too earlyPavel Begunkov
Nobody adjusts *nr_events (number of completed requests) before calling io_iopoll_getevents(), so the passed @min shouldn't be adjusted as well. Othewise it can return less than initially asked @min without hitting need_resched(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-06io_uring: don't delay iopoll'ed req completionPavel Begunkov
->iopoll() may have completed current request, but instead of reaping it, io_do_iopoll() just continues with the next request in the list. As a result it can leave just polled and completed request in the list up until next syscall. Even outer loop in io_iopoll_getevents() doesn't help the situation. E.g. poll_list: req0 -> req1 If req0->iopoll() completed both requests, and @min<=1, then @req0 will be left behind. Check whether a req was completed after ->iopoll(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-05io_uring: fix lost cqe->flagsPavel Begunkov
Don't forget to fill cqe->flags properly in io_submit_flush_completions() Fixes: a1d7c393c4711 ("io_uring: enable READ/WRITE to use deferred completions") Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-05io_uring: keep queue_sqe()'s fail path separatelyPavel Begunkov
A preparation path, extracts error path into a separate block. It looks saner then calling req_set_fail_links() after io_put_req_find_next(), even though it have been working well. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-05io_uring: fix mis-refcounting linked timeoutsPavel Begunkov
io_prep_linked_timeout() sets REQ_F_LINK_TIMEOUT altering refcounting of the following linked request. After that someone should call io_queue_linked_timeout(), otherwise a submission reference of the linked timeout won't be ever dropped. That's what happens in io_steal_work() if io-wq decides to postpone linked request with io_wqe_enqueue(). io_queue_linked_timeout() can also be potentially called twice without synchronisation during re-submission, e.g. io_rw_resubmit(). There are the rules, whoever did io_prep_linked_timeout() must also call io_queue_linked_timeout(). To not do it twice, io_prep_linked_timeout() will return non NULL only for the first call. That's controlled by REQ_F_LINK_TIMEOUT flag. Also kill REQ_F_QUEUE_TIMEOUT. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-05io_uring: use new io_req_task_work_add() helper throughoutJens Axboe
Since we now have that in the 5.9 branch, convert the existing users of task_work_add() to use this new helper. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-05io_uring: abstract out task work runningJens Axboe
Provide a helper to run task_work instead of checking and running manually in a bunch of different spots. While doing so, also move the task run state setting where we run the task work. Then we can move it out of the callback helpers. This also helps ensure we only do this once per task_work list run, not per task_work item. Suggested-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-05Merge branch 'io_uring-5.8' into for-5.9/io_uringJens Axboe
Pull in task_work changes from the 5.8 series, as we'll need to apply the same kind of changes to other parts in the 5.9 branch. * io_uring-5.8: io_uring: fix regression with always ignoring signals in io_cqring_wait() io_uring: use signal based task_work running task_work: teach task_work_add() to do signal_wake_up()
2020-07-05Replace HTTP links with HTTPS ones: CIFSAlexander A. Klimov
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Link: https://lore.kernel.org/r/20200627103125.71828-1-grandmaster@al2klimov.de Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-07-05Merge tag 'io_uring-5.8-2020-07-05' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull io_uring fix from Jens Axboe: "Andres reported a regression with the fix that was merged earlier this week, where his setup of using signals to interrupt io_uring CQ waits no longer worked correctly. Fix this, and also limit our use of TWA_SIGNAL to the case where we need it, and continue using TWA_RESUME for task_work as before. Since the original is marked for 5.7 stable, let's flush this one out early" * tag 'io_uring-5.8-2020-07-05' of git://git.kernel.dk/linux-block: io_uring: fix regression with always ignoring signals in io_cqring_wait()
2020-07-04io_uring: fix regression with always ignoring signals in io_cqring_wait()Jens Axboe
When switching to TWA_SIGNAL for task_work notifications, we also made any signal based condition in io_cqring_wait() return -ERESTARTSYS. This breaks applications that rely on using signals to abort someone waiting for events. Check if we have a signal pending because of queued task_work, and repeat the signal check once we've run the task_work. This provides a reliable way of telling the two apart. Additionally, only use TWA_SIGNAL if we are using an eventfd. If not, we don't have the dependency situation described in the original commit, and we can get by with just using TWA_RESUME like we previously did. Fixes: ce593a6c480a ("io_uring: use signal based task_work running") Cc: stable@vger.kernel.org # v5.7 Reported-by: Andres Freund <andres@anarazel.de> Tested-by: Andres Freund <andres@anarazel.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-04exec: Remove do_execve_fileEric W. Biederman
Now that the last callser has been removed remove this code from exec. For anyone thinking of resurrecing do_execve_file please note that the code was buggy in several fundamental ways. - It did not ensure the file it was passed was read-only and that deny_write_access had been called on it. Which subtlely breaks invaniants in exec. - The caller of do_execve_file was expected to hold and put a reference to the file, but an extra reference for use by exec was not taken so that when exec put it's reference to the file an underflow occured on the file reference count. - The point of the interface was so that a pathname did not need to exist. Which breaks pathname based LSMs. Tetsuo Handa originally reported these issues[1]. While it was clear that deny_write_access was missing the fundamental incompatibility with the passed in O_RDWR filehandle was not immediately recognized. All of these issues were fixed by modifying the usermode driver code to have a path, so it did not need this hack. Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> [1] https://lore.kernel.org/linux-fsdevel/2a8775b4-1dd5-9d5c-aa42-9872445e0942@i-love.sakura.ne.jp/ v1: https://lkml.kernel.org/r/871rm2f0hi.fsf_-_@x220.int.ebiederm.org v2: https://lkml.kernel.org/r/87lfk54p0m.fsf_-_@x220.int.ebiederm.org Link: https://lkml.kernel.org/r/20200702164140.4468-10-ebiederm@xmission.com Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-07-03Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds
Pull sysctl fix from Al Viro: "Another regression fix for sysctl changes this cycle..." * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: Call sysctl_head_finish on error
2020-07-03Merge tag '5.8-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull cifs fixes from Steve French: "Eight cifs/smb3 fixes, most when specifying the multiuser mount flag. Five of the fixes are for stable" * tag '5.8-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: cifs: prevent truncation from long to int in wait_for_free_credits cifs: Fix the target file was deleted when rename failed. SMB3: Honor 'posix' flag for multiuser mounts SMB3: Honor 'handletimeout' flag for multiuser mounts SMB3: Honor lease disabling for multiuser mounts SMB3: Honor persistent/resilient handle flags for multiuser mounts SMB3: Honor 'seal' flag for multiuser mounts cifs: Display local UID details for SMB sessions in DebugData
2020-07-03Merge tag 'xfs-5.8-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull xfs fix from Darrick Wong: "Fix a use-after-free bug when the fs shuts down" * tag 'xfs-5.8-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: xfs: fix use-after-free on CIL context on shutdown
2020-07-03Merge tag 'gfs2-v5.8-rc3.fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2 Pull gfs2 fixes from Andreas Gruenbacher: "Various gfs2 fixes" * tag 'gfs2-v5.8-rc3.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: gfs2: The freeze glock should never be frozen gfs2: When freezing gfs2, use GL_EXACT and not GL_NOCACHE gfs2: read-only mounts should grab the sd_freeze_gl glock gfs2: freeze should work on read-only mounts gfs2: eliminate GIF_ORDERED in favor of list_empty gfs2: Don't sleep during glock hash walk gfs2: fix trans slab error when withdraw occurs inside log_flush gfs2: Don't return NULL from gfs2_inode_lookup
2020-07-03Call sysctl_head_finish on errorMatthew Wilcox (Oracle)
This error path returned directly instead of calling sysctl_head_finish(). Fixes: ef9d965bc8b6 ("sysctl: reject gigantic reads/write to sysctl files") Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-07-03gfs2: The freeze glock should never be frozenBob Peterson
Before this patch, some gfs2 code locked the freeze glock with LM_FLAG_NOEXP (Do not freeze) flag, and some did not. We never want to freeze the freeze glock, so this patch makes it consistently use LM_FLAG_NOEXP always. Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-07-03gfs2: When freezing gfs2, use GL_EXACT and not GL_NOCACHEBob Peterson
Before this patch, the freeze code in gfs2 specified GL_NOCACHE in several places. That's wrong because we always want to know the state of whether the file system is frozen. There was also a problem with freeze/thaw transitioning the glock from frozen (EX) to thawed (SH) because gfs2 will normally grant glocks in EX to processes that request it in SH mode, unless GL_EXACT is specified. Therefore, the freeze/thaw code, which tried to reacquire the glock in SH mode would get the glock in EX mode, and miss the transition from EX to SH. That made it think the thaw had completed normally, but since the glock was still cached in EX, other nodes could not freeze again. This patch removes the GL_NOCACHE flag to allow the freeze glock to be cached. It also adds the GL_EXACT flag so the glock is fully transitioned from EX to SH, thereby allowing future freeze operations. Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-07-03gfs2: read-only mounts should grab the sd_freeze_gl glockBob Peterson
Before this patch, only read-write mounts would grab the freeze glock in read-only mode, as part of gfs2_make_fs_rw. So the freeze glock was never initialized. That meant requests to freeze, which request the glock in EX, were granted without any state transition. That meant you could mount a gfs2 file system, which is currently frozen on a different cluster node, in read-only mode. This patch makes read-only mounts lock the freeze glock in SH mode, which will block for file systems that are frozen on another node. Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-07-03gfs2: freeze should work on read-only mountsBob Peterson
Before this patch, function freeze_go_sync, called when promoting the freeze glock, was testing for the SDF_JOURNAL_LIVE superblock flag. That's only set for read-write mounts. Read-only mounts don't use a journal, so the bit is never set, so the freeze never happened. This patch removes the check for SDF_JOURNAL_LIVE for freeze requests but still checks it when deciding whether to flush a journal. Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-07-03gfs2: eliminate GIF_ORDERED in favor of list_emptyBob Peterson
In several places, we used the GIF_ORDERED inode flag to determine if an inode was on the ordered writes list. However, since we always held the sd_ordered_lock spin_lock during the manipulation, we can just as easily check list_empty(&ip->i_ordered) instead. This allows us to keep more than one ordered writes list to make journal writing improvements. This patch eliminates GIF_ORDERED in favor of checking list_empty. Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2020-07-02Merge tag 'nfsd-5.8-1' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd fixes from Bruce Fields: "Fixes for a umask bug on exported filesystems lacking ACL support, a leak and a module unloading bug in the /proc/fs/nfsd/clients/ code, and a compile warning" * tag 'nfsd-5.8-1' of git://linux-nfs.org/~bfields/linux: SUNRPC: Add missing definition of ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE nfsd: fix nfsdfs inode reference count leak nfsd4: fix nfsdfs reference count loop nfsd: apply umask on fs without ACL support
2020-07-02Merge tag 'io_uring-5.8-2020-07-01' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull io_uring fixes from Jens Axboe: "One fix in here, for a regression in 5.7 where a task is waiting in the kernel for a condition, but that condition won't become true until task_work is run. And the task_work can't be run exactly because the task is waiting in the kernel, so we'll never make any progress. One example of that is registering an eventfd and queueing io_uring work, and then the task goes and waits in eventfd read with the expectation that it'll get woken (and read an event) when the io_uring request completes. The io_uring request is finished through task_work, which won't get run while the task is looping in eventfd read" * tag 'io_uring-5.8-2020-07-01' of git://git.kernel.dk/linux-block: io_uring: use signal based task_work running task_work: teach task_work_add() to do signal_wake_up()
2020-07-02btrfs: reset tree root pointer after error in init_tree_rootsJosef Bacik
Eric reported an issue where mounting -o recovery with a fuzzed fs resulted in a kernel panic. This is because we tried to free the tree node, except it was an error from the read. Fix this by properly resetting the tree_root->node == NULL in this case. The panic was the following BTRFS warning (device loop0): failed to read tree root BUG: kernel NULL pointer dereference, address: 000000000000001f RIP: 0010:free_extent_buffer+0xe/0x90 [btrfs] Call Trace: free_root_extent_buffers.part.0+0x11/0x30 [btrfs] free_root_pointers+0x1a/0xa2 [btrfs] open_ctree+0x1776/0x18a5 [btrfs] btrfs_mount_root.cold+0x13/0xfa [btrfs] ? selinux_fs_context_parse_param+0x37/0x80 legacy_get_tree+0x27/0x40 vfs_get_tree+0x25/0xb0 fc_mount+0xe/0x30 vfs_kern_mount.part.0+0x71/0x90 btrfs_mount+0x147/0x3e0 [btrfs] ? cred_has_capability+0x7c/0x120 ? legacy_get_tree+0x27/0x40 legacy_get_tree+0x27/0x40 vfs_get_tree+0x25/0xb0 do_mount+0x735/0xa40 __x64_sys_mount+0x8e/0xd0 do_syscall_64+0x4d/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Nik says: this is problematic only if we fail on the last iteration of the loop as this results in init_tree_roots returning err value with tree_root->node = -ERR. Subsequently the caller does: fail_tree_roots which calls free_root_pointers on the bogus value. Reported-by: Eric Sandeen <sandeen@redhat.com> Fixes: b8522a1e5f42 ("btrfs: Factor out tree roots initialization during mount") CC: stable@vger.kernel.org # 5.5+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add details how the pointer gets dereferenced ] Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-02btrfs: fix reclaim_size counter leak after stealing from global reserveFilipe Manana
Commit 7f9fe614407692 ("btrfs: improve global reserve stealing logic"), added in the 5.8 merge window, introduced another leak for the space_info's reclaim_size counter. This is very often triggered by the test cases generic/269 and generic/416 from fstests, producing a stack trace like the following during unmount: [37079.155499] ------------[ cut here ]------------ [37079.156844] WARNING: CPU: 2 PID: 2000423 at fs/btrfs/block-group.c:3422 btrfs_free_block_groups+0x2eb/0x300 [btrfs] [37079.158090] Modules linked in: dm_snapshot btrfs dm_thin_pool (...) [37079.164440] CPU: 2 PID: 2000423 Comm: umount Tainted: G W 5.7.0-rc7-btrfs-next-62 #1 [37079.165422] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), (...) [37079.167384] RIP: 0010:btrfs_free_block_groups+0x2eb/0x300 [btrfs] [37079.168375] Code: bd 58 ff ff ff 00 4c 8d (...) [37079.170199] RSP: 0018:ffffaa53875c7de0 EFLAGS: 00010206 [37079.171120] RAX: ffff98099e701cf8 RBX: ffff98099e2d4000 RCX: 0000000000000000 [37079.172057] RDX: 0000000000000001 RSI: ffffffffc0acc5b1 RDI: 00000000ffffffff [37079.173002] RBP: ffff98099e701cf8 R08: 0000000000000000 R09: 0000000000000000 [37079.173886] R10: 0000000000000000 R11: 0000000000000000 R12: ffff98099e701c00 [37079.174730] R13: ffff98099e2d5100 R14: dead000000000122 R15: dead000000000100 [37079.175578] FS: 00007f4d7d0a5840(0000) GS:ffff9809ec600000(0000) knlGS:0000000000000000 [37079.176434] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [37079.177289] CR2: 0000559224dcc000 CR3: 000000012207a004 CR4: 00000000003606e0 [37079.178152] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [37079.178935] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [37079.179675] Call Trace: [37079.180419] close_ctree+0x291/0x2d1 [btrfs] [37079.181162] generic_shutdown_super+0x6c/0x100 [37079.181898] kill_anon_super+0x14/0x30 [37079.182641] btrfs_kill_super+0x12/0x20 [btrfs] [37079.183371] deactivate_locked_super+0x31/0x70 [37079.184012] cleanup_mnt+0x100/0x160 [37079.184650] task_work_run+0x68/0xb0 [37079.185284] exit_to_usermode_loop+0xf9/0x100 [37079.185920] do_syscall_64+0x20d/0x260 [37079.186556] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [37079.187197] RIP: 0033:0x7f4d7d2d9357 [37079.187836] Code: eb 0b 00 f7 d8 64 89 01 48 (...) [37079.189180] RSP: 002b:00007ffee4e0d368 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [37079.189845] RAX: 0000000000000000 RBX: 00007f4d7d3fb224 RCX: 00007f4d7d2d9357 [37079.190515] RDX: ffffffffffffff78 RSI: 0000000000000000 RDI: 0000559224dc5c90 [37079.191173] RBP: 0000559224dc1970 R08: 0000000000000000 R09: 00007ffee4e0c0e0 [37079.191815] R10: 0000559224dc7b00 R11: 0000000000000246 R12: 0000000000000000 [37079.192451] R13: 0000559224dc5c90 R14: 0000559224dc1a80 R15: 0000559224dc1ba0 [37079.193096] irq event stamp: 0 [37079.193729] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [37079.194379] hardirqs last disabled at (0): [<ffffffff97ab8935>] copy_process+0x755/0x1ea0 [37079.195033] softirqs last enabled at (0): [<ffffffff97ab8935>] copy_process+0x755/0x1ea0 [37079.195700] softirqs last disabled at (0): [<0000000000000000>] 0x0 [37079.196318] ---[ end trace b32710d864dea887 ]--- In the past commit d611add48b717a ("btrfs: fix reclaim counter leak of space_info objects") fixed similar cases. That commit however has a date more recent (April 7 2020) then the commit mentioned before (March 13 2020), however it was merged in kernel 5.7 while the older commit, which introduces a new leak, was merged only in the 5.8 merge window. So the leak sneaked in unnoticed. Fix this by making steal_from_global_rsv() remove the ticket using the helper remove_ticket(), which decrements the reclaim_size counter of the space_info object. Fixes: 7f9fe614407692 ("btrfs: improve global reserve stealing logic") Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-02btrfs: fix fatal extent_buffer readahead vs releasepage raceBoris Burkov
Under somewhat convoluted conditions, it is possible to attempt to release an extent_buffer that is under io, which triggers a BUG_ON in btrfs_release_extent_buffer_pages. This relies on a few different factors. First, extent_buffer reads done as readahead for searching use WAIT_NONE, so they free the local extent buffer reference while the io is outstanding. However, they should still be protected by TREE_REF. However, if the system is doing signficant reclaim, and simultaneously heavily accessing the extent_buffers, it is possible for releasepage to race with two concurrent readahead attempts in a way that leaves TREE_REF unset when the readahead extent buffer is released. Essentially, if two tasks race to allocate a new extent_buffer, but the winner who attempts the first io is rebuffed by a page being locked (likely by the reclaim itself) then the loser will still go ahead with issuing the readahead. The loser's call to find_extent_buffer must also race with the reclaim task reading the extent_buffer's refcount as 1 in a way that allows the reclaim to re-clear the TREE_REF checked by find_extent_buffer. The following represents an example execution demonstrating the race: CPU0 CPU1 CPU2 reada_for_search reada_for_search readahead_tree_block readahead_tree_block find_create_tree_block find_create_tree_block alloc_extent_buffer alloc_extent_buffer find_extent_buffer // not found allocates eb lock pages associate pages to eb insert eb into radix tree set TREE_REF, refs == 2 unlock pages read_extent_buffer_pages // WAIT_NONE not uptodate (brand new eb) lock_page if !trylock_page goto unlock_exit // not an error free_extent_buffer release_extent_buffer atomic_dec_and_test refs to 1 find_extent_buffer // found try_release_extent_buffer take refs_lock reads refs == 1; no io atomic_inc_not_zero refs to 2 mark_buffer_accessed check_buffer_tree_ref // not STALE, won't take refs_lock refs == 2; TREE_REF set // no action read_extent_buffer_pages // WAIT_NONE clear TREE_REF release_extent_buffer atomic_dec_and_test refs to 1 unlock_page still not uptodate (CPU1 read failed on trylock_page) locks pages set io_pages > 0 submit io return free_extent_buffer release_extent_buffer dec refs to 0 delete from radix tree btrfs_release_extent_buffer_pages BUG_ON(io_pages > 0)!!! We observe this at a very low rate in production and were also able to reproduce it in a test environment by introducing some spurious delays and by introducing probabilistic trylock_page failures. To fix it, we apply check_tree_ref at a point where it could not possibly be unset by a competing task: after io_pages has been incremented. All the codepaths that clear TREE_REF check for io, so they would not be able to clear it after this point until the io is done. Stack trace, for reference: [1417839.424739] ------------[ cut here ]------------ [1417839.435328] kernel BUG at fs/btrfs/extent_io.c:4841! [1417839.447024] invalid opcode: 0000 [#1] SMP [1417839.502972] RIP: 0010:btrfs_release_extent_buffer_pages+0x20/0x1f0 [1417839.517008] Code: ed e9 ... [1417839.558895] RSP: 0018:ffffc90020bcf798 EFLAGS: 00010202 [1417839.570816] RAX: 0000000000000002 RBX: ffff888102d6def0 RCX: 0000000000000028 [1417839.586962] RDX: 0000000000000002 RSI: ffff8887f0296482 RDI: ffff888102d6def0 [1417839.603108] RBP: ffff88885664a000 R08: 0000000000000046 R09: 0000000000000238 [1417839.619255] R10: 0000000000000028 R11: ffff88885664af68 R12: 0000000000000000 [1417839.635402] R13: 0000000000000000 R14: ffff88875f573ad0 R15: ffff888797aafd90 [1417839.651549] FS: 00007f5a844fa700(0000) GS:ffff88885f680000(0000) knlGS:0000000000000000 [1417839.669810] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [1417839.682887] CR2: 00007f7884541fe0 CR3: 000000049f609002 CR4: 00000000003606e0 [1417839.699037] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [1417839.715187] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [1417839.731320] Call Trace: [1417839.737103] release_extent_buffer+0x39/0x90 [1417839.746913] read_block_for_search.isra.38+0x2a3/0x370 [1417839.758645] btrfs_search_slot+0x260/0x9b0 [1417839.768054] btrfs_lookup_file_extent+0x4a/0x70 [1417839.778427] btrfs_get_extent+0x15f/0x830 [1417839.787665] ? submit_extent_page+0xc4/0x1c0 [1417839.797474] ? __do_readpage+0x299/0x7a0 [1417839.806515] __do_readpage+0x33b/0x7a0 [1417839.815171] ? btrfs_releasepage+0x70/0x70 [1417839.824597] extent_readpages+0x28f/0x400 [1417839.833836] read_pages+0x6a/0x1c0 [1417839.841729] ? startup_64+0x2/0x30 [1417839.849624] __do_page_cache_readahead+0x13c/0x1a0 [1417839.860590] filemap_fault+0x6c7/0x990 [1417839.869252] ? xas_load+0x8/0x80 [1417839.876756] ? xas_find+0x150/0x190 [1417839.884839] ? filemap_map_pages+0x295/0x3b0 [1417839.894652] __do_fault+0x32/0x110 [1417839.902540] __handle_mm_fault+0xacd/0x1000 [1417839.912156] handle_mm_fault+0xaa/0x1c0 [1417839.921004] __do_page_fault+0x242/0x4b0 [1417839.930044] ? page_fault+0x8/0x30 [1417839.937933] page_fault+0x1e/0x30 [1417839.945631] RIP: 0033:0x33c4bae [1417839.952927] Code: Bad RIP value. [1417839.960411] RSP: 002b:00007f5a844f7350 EFLAGS: 00010206 [1417839.972331] RAX: 000000000000006e RBX: 1614b3ff6a50398a RCX: 0000000000000000 [1417839.988477] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002 [1417840.004626] RBP: 00007f5a844f7420 R08: 000000000000006e R09: 00007f5a94aeccb8 [1417840.020784] R10: 00007f5a844f7350 R11: 0000000000000000 R12: 00007f5a94aecc79 [1417840.036932] R13: 00007f5a94aecc78 R14: 00007f5a94aecc90 R15: 00007f5a94aecc40 CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-02btrfs: convert comments to fallthrough annotationsMarcos Paulo de Souza
Convert fall through comments to the pseudo-keyword which is now the preferred way. Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-01cifs: prevent truncation from long to int in wait_for_free_creditsRonnie Sahlberg
The wait_event_... defines evaluate to long so we should not assign it an int as this may truncate the value. Reported-by: Marshall Midden <marshallmidden@gmail.com> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2020-07-01cifs: Fix the target file was deleted when rename failed.Zhang Xiaoxu
When xfstest generic/035, we found the target file was deleted if the rename return -EACESS. In cifs_rename2, we unlink the positive target dentry if rename failed with EACESS or EEXIST, even if the target dentry is positived before rename. Then the existing file was deleted. We should just delete the target file which created during the rename. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2020-07-01SMB3: Honor 'posix' flag for multiuser mountsPaul Aurich
The flag from the primary tcon needs to be copied into the volume info so that cifs_get_tcon will try to enable extensions on the per-user tcon. At that point, since posix extensions must have already been enabled on the superblock, don't try to needlessly adjust the mount flags. Fixes: ce558b0e17f8 ("smb3: Add posix create context for smb3.11 posix mounts") Fixes: b326614ea215 ("smb3: allow "posix" mount option to enable new SMB311 protocol extensions") Signed-off-by: Paul Aurich <paul@darkrain42.org> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com>