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2019-04-17udf: fix an uninitialized read bug and remove dead codeWenwen Wang
In udf_lookup(), the pointer 'fi' is a local variable initialized by the return value of the function call udf_find_entry(). However, if the macro 'UDF_RECOVERY' is defined, this variable will become uninitialized if the else branch is not taken, which can potentially cause incorrect results in the following execution. To fix this issue, this patch drops the whole code in the ifdef 'UDF_RECOVERY' region, as it is dead code. Signed-off-by: Wenwen Wang <wang6495@umn.edu> Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-16fscrypt: use READ_ONCE() to access ->i_crypt_infoEric Biggers
->i_crypt_info starts out NULL and may later be locklessly set to a non-NULL value by the cmpxchg() in fscrypt_get_encryption_info(). But ->i_crypt_info is used directly, which technically is incorrect. It's a data race, and it doesn't include the data dependency barrier needed to safely dereference the pointer on at least one architecture. Fix this by using READ_ONCE() instead. Note: we don't need to use smp_load_acquire(), since dereferencing the pointer only requires a data dependency barrier, which is already included in READ_ONCE(). We also don't need READ_ONCE() in places where ->i_crypt_info is unconditionally dereferenced, since it must have already been checked. Also downgrade the cmpxchg() to cmpxchg_release(), since RELEASE semantics are sufficient on the write side. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-16fscrypt: remove WARN_ON_ONCE() when decryption failsEric Biggers
If decrypting a block fails, fscrypt did a WARN_ON_ONCE(). But WARN is meant for kernel bugs, which this isn't; this could be hit by fuzzers using fault injection, for example. Also, there is already a proper warning message logged in fscrypt_do_page_crypto(), so the WARN doesn't add much. Just remove the unnessary WARN. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-16fscrypt: drop inode argument from fscrypt_get_ctx()Eric Biggers
The only reason the inode is being passed to fscrypt_get_ctx() is to verify that the encryption key is available. However, all callers already ensure this because if we get as far as trying to do I/O to an encrypted file without the key, there's already a bug. Therefore, remove this unnecessary argument. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-04-16f2fs: data: fix warning Using plain integer as NULL pointerHariprasad Kelam
changed passing function argument "0 to NULL" to fix below sparse warning fs/f2fs/data.c:426:47: warning: Using plain integer as NULL pointer Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-04-16f2fs: add tracepoint for f2fs_file_write_iter()Chao Yu
This patch adds tracepoint for f2fs_file_write_iter(). Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-04-16xfs: merge adjacent io completions of the same typeDarrick J. Wong
It's possible for pagecache writeback to split up a large amount of work into smaller pieces for throttling purposes or to reduce the amount of time a writeback operation is pending. Whatever the reason, XFS can end up with a bunch of IO completions that call for the same operation to be performed on a contiguous extent mapping. Since mappings are extent based in XFS, we'd prefer to run fewer transactions when we can. When we're processing an ioend on the list of io completions, check to see if the next items on the list are both adjacent and of the same type. If so, we can merge the completions to reduce transaction overhead. On fast storage this doesn't seem to make much of a difference in performance, though the number of transactions for an overnight xfstests run seems to drop by ~5%. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-16xfs: remove unused m_data_workqueueDarrick J. Wong
Now that we're no longer using m_data_workqueue, remove it. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-16xfs: implement per-inode writeback completion queuesDarrick J. Wong
When scheduling writeback of dirty file data in the page cache, XFS uses IO completion workqueue items to ensure that filesystem metadata only updates after the write completes successfully. This is essential for converting unwritten extents to real extents at the right time and performing COW remappings. Unfortunately, XFS queues each IO completion work item to an unbounded workqueue, which means that the kernel can spawn dozens of threads to try to handle the items quickly. These threads need to take the ILOCK to update file metadata, which results in heavy ILOCK contention if a large number of the work items target a single file, which is inefficient. Worse yet, the writeback completion threads get stuck waiting for the ILOCK while holding transaction reservations, which can use up all available log reservation space. When that happens, metadata updates to other parts of the filesystem grind to a halt, even if the filesystem could otherwise have handled it. Even worse, if one of the things grinding to a halt happens to be a thread in the middle of a defer-ops finish holding the same ILOCK and trying to obtain more log reservation having exhausted the permanent reservation, we now have an ABBA deadlock - writeback completion has a transaction reserved and wants the ILOCK, and someone else has the ILOCK and wants a transaction reservation. Therefore, we create a per-inode writeback io completion queue + work item. When writeback finishes, it can add the ioend to the per-inode queue and let the single worker item process that queue. This dramatically cuts down on the number of kworkers and ILOCK contention in the system, and seems to have eliminated an occasional deadlock I was seeing while running generic/476. Testing with a program that simulates a heavy random-write workload to a single file demonstrates that the number of kworkers drops from approximately 120 threads per file to 1, without dramatically changing write bandwidth or pagecache access latency. Note that we leave the xfs-conv workqueue's max_active alone because we still want to be able to run ioend processing for as many inodes as the system can handle. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-16xfs: scrub should only cross-reference with healthy btreesDarrick J. Wong
Skip cross-referencing with a btree if the health report tells us that it's known to be bad. This should reduce the dmesg spew considerably. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-04-16xfs: scrub/repair should update filesystem metadata healthDarrick J. Wong
Now that we have the ability to track sick metadata in-core, make scrub and repair update those health assessments after doing work. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-04-16xfs: hoist the already_fixed variable to the scrub contextDarrick J. Wong
Now that we no longer memset the scrub context, we can move the already_fixed variable into the scrub context's state flags instead of passing around pointers to separate stack variables. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-04-16xfs: collapse scrub bool state flags into a single unsigned intDarrick J. Wong
Combine all the boolean state flags in struct xfs_scrub into a single unsigned int, because we're going to be adding more state flags soon. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-04-16xfs: refactor scrub context initializationDarrick J. Wong
It's a little silly how the memset in scrub context initialization forces us to declare stack variables to preserve context variables across a retry. Since the teardown functions already null out most of the ephemeral state (buffer pointers, btree cursors, etc.), just skip the memset and move the initialization as needed. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-04-16CIFS: keep FileInfo handle live during oplock breakAurelien Aptel
In the oplock break handler, writing pending changes from pages puts the FileInfo handle. If the refcount reaches zero it closes the handle and waits for any oplock break handler to return, thus causing a deadlock. To prevent this situation: * We add a wait flag to cifsFileInfo_put() to decide whether we should wait for running/pending oplock break handlers * We keep an additionnal reference of the SMB FileInfo handle so that for the rest of the handler putting the handle won't close it. - The ref is bumped everytime we queue the handler via the cifs_queue_oplock_break() helper. - The ref is decremented at the end of the handler This bug was triggered by xfstest 464. Also important fix to address the various reports of oops in smb2_push_mandatory_locks Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> CC: Stable <stable@vger.kernel.org>
2019-04-16cifs: fix handle leak in smb2_query_symlink()Ronnie Sahlberg
If we enter smb2_query_symlink() for something that is not a symlink and where the SMB2_open() would succeed we would never end up closing this handle and would thus leak a handle on the server. Fix this by immediately calling SMB2_close() on successfull open. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> CC: Stable <stable@vger.kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-04-16cifs: Fix lease buffer length errorZhangXiaoxu
There is a KASAN slab-out-of-bounds: BUG: KASAN: slab-out-of-bounds in _copy_from_iter_full+0x783/0xaa0 Read of size 80 at addr ffff88810c35e180 by task mount.cifs/539 CPU: 1 PID: 539 Comm: mount.cifs Not tainted 4.19 #10 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack+0xdd/0x12a print_address_description+0xa7/0x540 kasan_report+0x1ff/0x550 check_memory_region+0x2f1/0x310 memcpy+0x2f/0x80 _copy_from_iter_full+0x783/0xaa0 tcp_sendmsg_locked+0x1840/0x4140 tcp_sendmsg+0x37/0x60 inet_sendmsg+0x18c/0x490 sock_sendmsg+0xae/0x130 smb_send_kvec+0x29c/0x520 __smb_send_rqst+0x3ef/0xc60 smb_send_rqst+0x25a/0x2e0 compound_send_recv+0x9e8/0x2af0 cifs_send_recv+0x24/0x30 SMB2_open+0x35e/0x1620 open_shroot+0x27b/0x490 smb2_open_op_close+0x4e1/0x590 smb2_query_path_info+0x2ac/0x650 cifs_get_inode_info+0x1058/0x28f0 cifs_root_iget+0x3bb/0xf80 cifs_smb3_do_mount+0xe00/0x14c0 cifs_do_mount+0x15/0x20 mount_fs+0x5e/0x290 vfs_kern_mount+0x88/0x460 do_mount+0x398/0x31e0 ksys_mount+0xc6/0x150 __x64_sys_mount+0xea/0x190 do_syscall_64+0x122/0x590 entry_SYSCALL_64_after_hwframe+0x44/0xa9 It can be reproduced by the following step: 1. samba configured with: server max protocol = SMB2_10 2. mount -o vers=default When parse the mount version parameter, the 'ops' and 'vals' was setted to smb30, if negotiate result is smb21, just update the 'ops' to smb21, but the 'vals' is still smb30. When add lease context, the iov_base is allocated with smb21 ops, but the iov_len is initiallited with the smb30. Because the iov_len is longer than iov_base, when send the message, copy array out of bounds. we need to keep the 'ops' and 'vals' consistent. Fixes: 9764c02fcbad ("SMB3: Add support for multidialect negotiate (SMB2.1 and later)") Fixes: d5c7076b772a ("smb3: add smb3.1.1 to default dialect list") Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-04-16cifs: Fix use-after-free in SMB2_readZhangXiaoxu
There is a KASAN use-after-free: BUG: KASAN: use-after-free in SMB2_read+0x1136/0x1190 Read of size 8 at addr ffff8880b4e45e50 by task ln/1009 Should not release the 'req' because it will use in the trace. Fixes: eccb4422cf97 ("smb3: Add ftrace tracepoints for improved SMB3 debugging") Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org> 4.18+ Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-04-16cifs: Fix use-after-free in SMB2_writeZhangXiaoxu
There is a KASAN use-after-free: BUG: KASAN: use-after-free in SMB2_write+0x1342/0x1580 Read of size 8 at addr ffff8880b6a8e450 by task ln/4196 Should not release the 'req' because it will use in the trace. Fixes: eccb4422cf97 ("smb3: Add ftrace tracepoints for improved SMB3 debugging") Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org> 4.18+ Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-04-15Merge tag 'fsdax-fix-5.1-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull fsdax fix from Dan Williams: "A single filesystem-dax fix. It has been lingering in -next for a long while and there are no other fsdax fixes on the horizon: - Avoid a crash scenario with architectures like powerpc that require 'pgtable_deposit' for the zero page" * tag 'fsdax-fix-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: fs/dax: Deposit pagetable even when installing zero page
2019-04-15io_uring: fix possible deadlock between io_uring_{enter,register}Jens Axboe
If we have multiple threads, one doing io_uring_enter() while the other is doing io_uring_register(), we can run into a deadlock between the two. io_uring_register() must wait for existing users of the io_uring instance to exit. But it does so while holding the io_uring mutex. Callers of io_uring_enter() may need this mutex to make progress (and eventually exit). If we wait for users to exit in io_uring_register(), we can't do so with the io_uring mutex held without potentially risking a deadlock. Drop the io_uring mutex while waiting for existing callers to exit. This is safe and guaranteed to make forward progress, since we already killed the percpu ref before doing so. Hence later callers of io_uring_enter() will be rejected. Reported-by: syzbot+16dc03452dee970a0c3e@syzkaller.appspotmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-15fs/reiserfs/journal.c: Make remove_journal_hash staticBharath Vedartham
This fixes the -WDecl sparse warning in journal.c. Function was declared as static void but the definition was void. Signed-off-by: Bharath Vedartham <linux.bhar@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-14xfs: report inode health via bulkstatDarrick J. Wong
Use space in the bulkstat ioctl structure to report any problems observed with the inode. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-14xfs: report AG health via AG geometry ioctlDarrick J. Wong
Use the AG geometry info ioctl to report health status too. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-14xfs: report fs and rt health via geometry structureDarrick J. Wong
Use our newly expanded geometry structure to report the overall fs and realtime health status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-14xfs: add a new ioctl to describe allocation group geometryDarrick J. Wong
Add a new ioctl to describe an allocation group's geometry. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-14xfs: bump XFS_IOC_FSGEOMETRY to v5 structuresDave Chinner
Unfortunately, the V4 XFS_IOC_FSGEOMETRY structure is out of space so we can't just add a new field to it. Hence we need to bump the definition to V5 and and treat the V4 ioctl and structure similar to v1 to v3. While doing this, clean up all the definitions associated with the XFS_IOC_FSGEOMETRY ioctl. Signed-Off-By: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> [darrick: forward port to 5.1, expand structure size to 256 bytes] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-14xfs: clear BAD_SUMMARY if unmounting an unhealthy filesystemDarrick J. Wong
If we know the filesystem metadata isn't healthy during unmount, we want to encourage the administrator to run xfs_repair right away. We can't do this if BAD_SUMMARY will cause an unclean log unmount to force summary recalculation, so turn it off if the fs is bad. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-14xfs: replace the BAD_SUMMARY mount flag with the equivalent health codeDarrick J. Wong
Replace the BAD_SUMMARY mount flag with calls to the equivalent health tracking code. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-14xfs: track metadata health statusDarrick J. Wong
Add the necessary in-core metadata fields to keep track of which parts of the filesystem have been observed and which parts were observed to be unhealthy, and print a warning at unmount time if we have unfixed problems. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2019-04-14xfs,fstrim: fix to return correct minlenWang Shilong
This patch tries to address two problems: 1) return @minlen we used to trim to user space. 2) return EINVAL if granularity is larger than avg size, even most of cases, granularity is small(4K), but if devices return a lager granularity for some reaons (testing, bugs etc), fstrim should return failure directly. Signed-off-by: Wang Shilong <wshilong@ddn.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-04-14xfs: don't account extra agfl blocks as availableBrian Foster
The block allocation AG selection code has parameters that allow a caller to perform multiple allocations from a single AG and transaction (under certain conditions). The parameters specify the total block allocation count required by the transaction and the AG selection code selects and locks an AG that will be able to satisfy the overall requirement. If the available block accounting calculation turns out to be inaccurate and a subsequent allocation call fails with -ENOSPC, the resulting transaction cancel leads to filesystem shutdown because the transaction is dirty. This exact problem can be reproduced with a highly parallel space consumer and fsstress workload running long enough to a large filesystem against -ENOSPC conditions. A bmbt block allocation request made for inode extent to bmap format conversion after an extent allocation is expected to be satisfied by the same AG and the same transaction as the extent allocation. The bmbt block allocation fails, however, because the block availability of the AG has changed since the AG was selected (outside of the blocks used for the extent itself). The inconsistent block availability calculation is caused by the deferred block freeing behavior of the AGFL. This immediately removes extra blocks from the AGFL to free up AGFL slots, but rather than immediately freeing such blocks as was done in the past, the block free is deferred such that said blocks are not available for allocation until the current transaction commits. The AG selection logic currently considers all AGFL blocks as available and executes shortly before any extra AGFL blocks are freed. This means the block availability of the current AG can change before the first allocation even occurs, but in practice a failure is more likely to manifest via a subsequent allocation because extent allocation usually has a contiguity requirement larger than a single block that can't be satisfied from the AGFL. In general, XFS prefers operational robustness to absolute allocation efficiency. In other words, we prefer to return -ENOSPC slightly earlier at the expense of not being able to allocate every last block in an AG to avoid this kind of problem. As such, update the AG block availability calculation to consider extra AGFL blocks as unavailable since they are immediately removed following the calculation and will not become available until the current transaction commits. 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>
2019-04-14xfs: shutdown after buf release in iflush cluster abort pathBrian Foster
If xfs_iflush_cluster() fails due to corruption, the error path issues a shutdown and simulates an I/O completion to release the buffer. This code has a couple small problems. First, the shutdown sequence can issue a synchronous log force, which is unsafe to do with buffer locks held. Second, the simulated I/O completion does not guarantee the buffer is async and thus is unlocked and released. For example, if the last operation on the buffer was a read off disk prior to the corruption event, XBF_ASYNC is not set and the buffer is left locked and held upon return. This results in a memory leak as shown by the following message on module unload: BUG xfs_buf (...): Objects remaining in xfs_buf on __kmem_cache_shutdown() Fix both of these problems by setting XBF_ASYNC on the buffer prior to the simulated I/O error and performing the shutdown immediately after ioend processing when the buffer has been released. 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>
2019-04-14xfs: wake commit waiters on CIL abort before log item abortBrian Foster
XFS shutdown deadlocks have been reproduced by fstest generic/475. The deadlock signature involves log I/O completion running error handling to abort logged items and waiting for an inode cluster buffer lock in the buffer item unpin handler. The buffer lock is held by xfsaild attempting to flush an inode. The buffer happens to be pinned and so xfs_iflush() triggers an async log force to begin work required to get it unpinned. The log force is blocked waiting on the commit completion, which never occurs and thus leaves the filesystem deadlocked. The root problem is that aborted log I/O completion pots commit completion behind callback completion, which is unexpected for async log forces. Under normal running conditions, an async log force returns to the caller once the CIL ctx has been formatted/submitted and the commit completion event triggered at the tail end of xlog_cil_push(). If the filesystem has shutdown, however, we rely on xlog_cil_committed() to trigger the completion event and it happens to do so after running log item unpin callbacks. This makes it unsafe to invoke an async log force from contexts that hold locks that might also be required in log completion processing. To address this problem, wake commit completion waiters before aborting log items in the log I/O completion handler. This ensures that an async log force will not deadlock on held locks if the filesystem happens to shutdown. Note that it is still unsafe to issue a sync log force while holding such locks because a sync log force explicitly waits on the force completion, which occurs after log I/O completion processing. 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>
2019-04-14xfs: fix use after free in buf log item unlock assertBrian Foster
The xfs_buf_log_item ->iop_unlock() callback asserts that the buffer is unlocked when either non-stale or aborted. This assert occurs after the bli refcount has been dropped and the log item potentially freed. The aborted check is thus a potential use after free. This problem has been reproduced with KASAN enabled via generic/475. Fix up xfs_buf_item_unlock() to query aborted state before the bli reference is dropped to prevent a potential use after free. 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>
2019-04-14Merge branch 'page-refs' (page ref overflow)Linus Torvalds
Merge page ref overflow branch. Jann Horn reported that he can overflow the page ref count with sufficient memory (and a filesystem that is intentionally extremely slow). Admittedly it's not exactly easy. To have more than four billion references to a page requires a minimum of 32GB of kernel memory just for the pointers to the pages, much less any metadata to keep track of those pointers. Jann needed a total of 140GB of memory and a specially crafted filesystem that leaves all reads pending (in order to not ever free the page references and just keep adding more). Still, we have a fairly straightforward way to limit the two obvious user-controllable sources of page references: direct-IO like page references gotten through get_user_pages(), and the splice pipe page duplication. So let's just do that. * branch page-refs: fs: prevent page refcount overflow in pipe_buf_get mm: prevent get_user_pages() from overflowing page refcount mm: add 'try_get_page()' helper function mm: make page ref count overflow check tighter and more explicit
2019-04-14latency_top: Remove the ULONG_MAX stack trace hackeryThomas Gleixner
No architecture terminates the stack trace with ULONG_MAX anymore. The consumer terminates on the first zero entry or at the number of entries, so no functional change. Remove the cruft. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Potapenko <glider@google.com> Link: https://lkml.kernel.org/r/20190410103644.853527514@linutronix.de
2019-04-14fs: prevent page refcount overflow in pipe_buf_getMatthew Wilcox
Change pipe_buf_get() to return a bool indicating whether it succeeded in raising the refcount of the page (if the thing in the pipe is a page). This removes another mechanism for overflowing the page refcount. All callers converted to handle a failure. Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Matthew Wilcox <willy@infradead.org> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-04-13io_uring: drop io_file_put() 'file' argumentJens Axboe
Since the fget/fput handling was reworked in commit 09bb839434bd, we never call io_file_put() with state == NULL (and hence file != NULL) anymore. Remove that case. Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-13io_uring: only test SQPOLL cpu after we've verified itJens Axboe
We currently call cpu_possible() even if we don't use the CPU. Move the test under the SQ_AFF branch, which is the only place where we'll use the value. Do the cpu_possible() test AFTER we've limited it to a max of NR_CPUS. This avoids triggering the following warning: WARNING: CPU: 1 PID: 7600 at include/linux/cpumask.h:121 cpu_max_bits_warn if CONFIG_DEBUG_PER_CPU_MAPS is enabled. While in there, also move the SQ thread idle period assignment inside SETUP_SQPOLL, as we don't use it otherwise either. Reported-by: syzbot+cd714a07c6de2bc34293@syzkaller.appspotmail.com Fixes: 6c271ce2f1d5 ("io_uring: add submission polling") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-13io_uring: park SQPOLL thread if it's percpuJens Axboe
kthread expects this, or we can throw a warning on exit: WARNING: CPU: 0 PID: 7822 at kernel/kthread.c:399 __kthread_bind_mask+0x3b/0xc0 kernel/kthread.c:399 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 7822 Comm: syz-executor030 Not tainted 5.1.0-rc4-next-20190412 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 panic+0x2cb/0x72b kernel/panic.c:214 __warn.cold+0x20/0x46 kernel/panic.c:576 report_bug+0x263/0x2b0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:179 [inline] fixup_bug arch/x86/kernel/traps.c:174 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973 RIP: 0010:__kthread_bind_mask+0x3b/0xc0 kernel/kthread.c:399 Code: 48 89 fb e8 f7 ab 24 00 4c 89 e6 48 89 df e8 ac e1 02 00 31 ff 49 89 c4 48 89 c6 e8 7f ad 24 00 4d 85 e4 75 15 e8 d5 ab 24 00 <0f> 0b e8 ce ab 24 00 5b 41 5c 41 5d 41 5e 5d c3 e8 c0 ab 24 00 4c RSP: 0018:ffff8880a89bfbb8 EFLAGS: 00010293 RAX: ffff88808ca7a280 RBX: ffff8880a98e4380 RCX: ffffffff814bdd11 RDX: 0000000000000000 RSI: ffffffff814bdd1b RDI: 0000000000000007 RBP: ffff8880a89bfbd8 R08: ffff88808ca7a280 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff87691148 R14: ffff8880a98e43a0 R15: ffffffff81c91e10 __kthread_bind kernel/kthread.c:412 [inline] kthread_unpark+0x123/0x160 kernel/kthread.c:480 kthread_stop+0xfa/0x6c0 kernel/kthread.c:556 io_sq_thread_stop fs/io_uring.c:2057 [inline] io_sq_thread_stop fs/io_uring.c:2052 [inline] io_finish_async+0xab/0x180 fs/io_uring.c:2064 io_ring_ctx_free fs/io_uring.c:2534 [inline] io_ring_ctx_wait_and_kill+0x133/0x510 fs/io_uring.c:2591 io_uring_release+0x42/0x50 fs/io_uring.c:2599 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x90a/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:980 __do_sys_exit_group kernel/exit.c:991 [inline] __se_sys_exit_group kernel/exit.c:989 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:989 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Reported-by: syzbot+6d4a92619eb0ad08602b@syzkaller.appspotmail.com Fixes: 6c271ce2f1d5 ("io_uring: add submission polling") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-13Merge tag 'for-linus-20190412' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "Set of fixes that should go into this round. This pull is larger than I'd like at this time, but there's really no specific reason for that. Some are fixes for issues that went into this merge window, others are not. Anyway, this contains: - Hardware queue limiting for virtio-blk/scsi (Dongli) - Multi-page bvec fixes for lightnvm pblk - Multi-bio dio error fix (Jason) - Remove the cache hint from the io_uring tool side, since we didn't move forward with that (me) - Make io_uring SETUP_SQPOLL root restricted (me) - Fix leak of page in error handling for pc requests (Jérôme) - Fix BFQ regression introduced in this merge window (Paolo) - Fix break logic for bio segment iteration (Ming) - Fix NVMe cancel request error handling (Ming) - NVMe pull request with two fixes (Christoph): - fix the initial CSN for nvme-fc (James) - handle log page offsets properly in the target (Keith)" * tag 'for-linus-20190412' of git://git.kernel.dk/linux-block: block: fix the return errno for direct IO nvmet: fix discover log page when offsets are used nvme-fc: correct csn initialization and increments on error block: do not leak memory in bio_copy_user_iov() lightnvm: pblk: fix crash in pblk_end_partial_read due to multipage bvecs nvme: cancel request synchronously blk-mq: introduce blk_mq_complete_request_sync() scsi: virtio_scsi: limit number of hw queues by nr_cpu_ids virtio-blk: limit number of hw queues by nr_cpu_ids block, bfq: fix use after free in bfq_bfqq_expire io_uring: restrict IORING_SETUP_SQPOLL to root tools/io_uring: remove IOCQE_FLAG_CACHEHIT block: don't use for-inside-for in bio_for_each_segment_all
2019-04-13Merge tag 'nfs-for-5.1-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client bugfixes from Trond Myklebust: "Highlights include: Stable fix: - Fix a deadlock in close() due to incorrect draining of RDMA queues Bugfixes: - Revert "SUNRPC: Micro-optimise when the task is known not to be sleeping" as it is causing stack overflows - Fix a regression where NFSv4 getacl and fs_locations stopped working - Forbid setting AF_INET6 to "struct sockaddr_in"->sin_family. - Fix xfstests failures due to incorrect copy_file_range() return values" * tag 'nfs-for-5.1-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: Revert "SUNRPC: Micro-optimise when the task is known not to be sleeping" NFSv4.1 fix incorrect return value in copy_file_range xprtrdma: Fix helper that drains the transport NFS: Fix handling of reply page vector NFS: Forbid setting AF_INET6 to "struct sockaddr_in"->sin_family.
2019-04-13afs: Fix in-progess ops to ignore server-level callback invalidationDavid Howells
The in-kernel afs filesystem client counts the number of server-level callback invalidation events (CB.InitCallBackState* RPC operations) that it receives from the server. This is stored in cb_s_break in various structures, including afs_server and afs_vnode. If an inode is examined by afs_validate(), say, the afs_server copy is compared, along with other break counters, to those in afs_vnode, and if one or more of the counters do not match, it is considered that the server's callback promise is broken. At points where this happens, AFS_VNODE_CB_PROMISED is cleared to indicate that the status must be refetched from the server. afs_validate() issues an FS.FetchStatus operation to get updated metadata - and based on the updated data_version may invalidate the pagecache too. However, the break counters are also used to determine whether to note a new callback in the vnode (which would set the AFS_VNODE_CB_PROMISED flag) and whether to cache the permit data included in the YFSFetchStatus record by the server. The problem comes when the server sends us a CB.InitCallBackState op. The first such instance doesn't cause cb_s_break to be incremented, but rather causes AFS_SERVER_FL_NEW to be cleared - but thereafter, say some hours after last use and all the volumes have been automatically unmounted and the server has forgotten about the client[*], this *will* likely cause an increment. [*] There are other circumstances too, such as the server restarting or needing to make space in its callback table. Note that the server won't send us a CB.InitCallBackState op until we talk to it again. So what happens is: (1) A mount for a new volume is attempted, a inode is created for the root vnode and vnode->cb_s_break and AFS_VNODE_CB_PROMISED aren't set immediately, as we don't have a nominated server to talk to yet - and we may iterate through a few to find one. (2) Before the operation happens, afs_fetch_status(), say, notes in the cursor (fc.cb_break) the break counter sum from the vnode, volume and server counters, but the server->cb_s_break is currently 0. (3) We send FS.FetchStatus to the server. The server sends us back CB.InitCallBackState. We increment server->cb_s_break. (4) Our FS.FetchStatus completes. The reply includes a callback record. (5) xdr_decode_AFSCallBack()/xdr_decode_YFSCallBack() check to see whether the callback promise was broken by checking the break counter sum from step (2) against the current sum. This fails because of step (3), so we don't set the callback record and, importantly, don't set AFS_VNODE_CB_PROMISED on the vnode. This does not preclude the syscall from progressing, and we don't loop here rechecking the status, but rather assume it's good enough for one round only and will need to be rechecked next time. (6) afs_validate() it triggered on the vnode, probably called from d_revalidate() checking the parent directory. (7) afs_validate() notes that AFS_VNODE_CB_PROMISED isn't set, so doesn't update vnode->cb_s_break and assumes the vnode to be invalid. (8) afs_validate() needs to calls afs_fetch_status(). Go back to step (2) and repeat, every time the vnode is validated. This primarily affects volume root dir vnodes. Everything subsequent to those inherit an already incremented cb_s_break upon mounting. The issue is that we assume that the callback record and the cached permit information in a reply from the server can't be trusted after getting a server break - but this is wrong since the server makes sure things are done in the right order, holding up our ops if necessary[*]. [*] There is an extremely unlikely scenario where a reply from before the CB.InitCallBackState could get its delivery deferred till after - at which point we think we have a promise when we don't. This, however, requires unlucky mass packet loss to one call. AFS_SERVER_FL_NEW tries to paper over the cracks for the initial mount from a server we've never contacted before, but this should be unnecessary. It's also further insulated from the problem on an initial mount by querying the server first with FS.GetCapabilities, which triggers the CB.InitCallBackState. Fix this by (1) Remove AFS_SERVER_FL_NEW. (2) In afs_calc_vnode_cb_break(), don't include cb_s_break in the calculation. (3) In afs_cb_is_broken(), don't include cb_s_break in the check. Signed-off-by: David Howells <dhowells@redhat.com>
2019-04-13afs: Unlock pages for __pagevec_release()Marc Dionne
__pagevec_release() complains loudly if any page in the vector is still locked. The pages need to be locked for generic_error_remove_page(), but that function doesn't actually unlock them. Unlock the pages afterwards. Signed-off-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Jonathan Billings <jsbillin@umich.edu>
2019-04-13afs: Differentiate abort due to unmarshalling from other errorsDavid Howells
Differentiate an abort due to an unmarshalling error from an abort due to other errors, such as ENETUNREACH. It doesn't make sense to set abort code RXGEN_*_UNMARSHAL in such a case, so use RX_USER_ABORT instead. Signed-off-by: David Howells <dhowells@redhat.com>
2019-04-13afs: Avoid section confusion in CM_NAMEAndi Kleen
__tracepoint_str cannot be const because the tracepoint_str section is not read-only. Remove the stray const. Cc: dhowells@redhat.com Cc: viro@zeniv.linux.org.uk Signed-off-by: Andi Kleen <ak@linux.intel.com>
2019-04-13afs: avoid deprecated get_seconds()Arnd Bergmann
get_seconds() has a limited range on 32-bit architectures and is deprecated because of that. While AFS uses the same limits for its inode timestamps on the wire protocol, let's just use the simpler current_time() as we do for other file systems. This will still zero out the 'tv_nsec' field of the timestamps internally. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David Howells <dhowells@redhat.com>
2019-04-12afs: Check for rxrpc call completion in wait loopMarc Dionne
Check the state of the rxrpc call backing an afs call in each iteration of the call wait loop in case the rxrpc call has already been terminated at the rxrpc layer. Interrupt the wait loop and mark the afs call as complete if the rxrpc layer call is complete. There were cases where rxrpc errors were not passed up to afs, which could result in this loop waiting forever for an afs call to transition to AFS_CALL_COMPLETE while the rx call was already complete. Signed-off-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-12rxrpc: Make rxrpc_kernel_check_life() indicate if call completedMarc Dionne
Make rxrpc_kernel_check_life() pass back the life counter through the argument list and return true if the call has not yet completed. Suggested-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>