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2019-05-22smb3: display session id in debug dataSteve French1-0/+2
commit b63a9de02d64ecd5ff0749e90253f5b30ba5b9c0 upstream. Displaying the session id in /proc/fs/cifs/DebugData is needed in order to correlate Linux client information with network and server traces for many common support scenarios. Turned out to be very important for debugging. Signed-off-by: Steve French <stfrench@microsoft.com> CC: Stable <stable@vger.kernel.org> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22jbd2: fix potential double freeChengguang Xu3-33/+56
commit 0d52154bb0a700abb459a2cbce0a30fc2549b67e upstream. When failing from creating cache jbd2_inode_cache, we will destroy the previously created cache jbd2_handle_cache twice. This patch fixes this by moving each cache initialization/destruction to its own separate, individual function. Signed-off-by: Chengguang Xu <cgxu519@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ext4: avoid panic during forced reboot due to aborted journalJan Kara1-1/+1
commit 2c1d0e3631e5732dba98ef49ac0bec1388776793 upstream. Handling of aborted journal is a special code path different from standard ext4_error() one and it can call panic() as well. Commit 1dc1097ff60e ("ext4: avoid panic during forced reboot") forgot to update this path so fix that omission. Fixes: 1dc1097ff60e ("ext4: avoid panic during forced reboot") Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org # 5.1 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ext4: fix use-after-free in dx_release()Sahitya Tummala1-1/+4
commit 08fc98a4d6424af66eb3ac4e2cedd2fc927ed436 upstream. The buffer_head (frames[0].bh) and it's corresping page can be potentially free'd once brelse() is done inside the for loop but before the for loop exits in dx_release(). It can be free'd in another context, when the page cache is flushed via drop_caches_sysctl_handler(). This results into below data abort when accessing info->indirect_levels in dx_release(). Unable to handle kernel paging request at virtual address ffffffc17ac3e01e Call trace: dx_release+0x70/0x90 ext4_htree_fill_tree+0x2d4/0x300 ext4_readdir+0x244/0x6f8 iterate_dir+0xbc/0x160 SyS_getdents64+0x94/0x174 Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ext4: fix data corruption caused by overlapping unaligned and aligned IOLukas Czerner1-0/+7
commit 57a0da28ced8707cb9f79f071a016b9d005caf5a upstream. Unaligned AIO must be serialized because the zeroing of partial blocks of unaligned AIO can result in data corruption in case it's overlapping another in flight IO. Currently we wait for all unwritten extents before we submit unaligned AIO which protects data in case of unaligned AIO is following overlapping IO. However if a unaligned AIO is followed by overlapping aligned AIO we can still end up corrupting data. To fix this, we must make sure that the unaligned AIO is the only IO in flight by waiting for unwritten extents conversion not just before the IO submission, but right after it as well. This problem can be reproduced by xfstest generic/538 Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ext4: zero out the unused memory region in the extent tree blockSriram Rajagopalan1-2/+15
commit 592acbf16821288ecdc4192c47e3774a4c48bb64 upstream. This commit zeroes out the unused memory region in the buffer_head corresponding to the extent metablock after writing the extent header and the corresponding extent node entries. This is done to prevent random uninitialized data from getting into the filesystem when the extent block is synced. This fixes CVE-2019-11833. Signed-off-by: Sriram Rajagopalan <sriramr@arista.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22fs/writeback.c: use rcu_barrier() to wait for inflight wb switches going ↵Jiufei Xue1-3/+8
into workqueue when umount commit ec084de929e419e51bcdafaafe567d9e7d0273b7 upstream. synchronize_rcu() didn't wait for call_rcu() callbacks, so inode wb switch may not go to the workqueue after synchronize_rcu(). Thus previous scheduled switches was not finished even flushing the workqueue, which will cause a NULL pointer dereferenced followed below. VFS: Busy inodes after unmount of vdd. Self-destruct in 5 seconds. Have a nice day... BUG: unable to handle kernel NULL pointer dereference at 0000000000000278 evict+0xb3/0x180 iput+0x1b0/0x230 inode_switch_wbs_work_fn+0x3c0/0x6a0 worker_thread+0x4e/0x490 ? process_one_work+0x410/0x410 kthread+0xe6/0x100 ret_from_fork+0x39/0x50 Replace the synchronize_rcu() call with a rcu_barrier() to wait for all pending callbacks to finish. And inc isw_nr_in_flight after call_rcu() in inode_switch_wbs() to make more sense. Link: http://lkml.kernel.org/r/20190429024108.54150-1-jiufei.xue@linux.alibaba.com Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com> Acked-by: Tejun Heo <tj@kernel.org> Suggested-by: Tejun Heo <tj@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22Btrfs: fix race between send and deduplication that lead to failures and crashesFilipe Manana3-1/+50
commit 62d54f3a7fa27ef6a74d6cdf643ce04beba3afa7 upstream. Send operates on read only trees and expects them to never change while it is using them. This is part of its initial design, and this expection is due to two different reasons: 1) When it was introduced, no operations were allowed to modifiy read-only subvolumes/snapshots (including defrag for example). 2) It keeps send from having an impact on other filesystem operations. Namely send does not need to keep locks on the trees nor needs to hold on to transaction handles and delay transaction commits. This ends up being a consequence of the former reason. However the deduplication feature was introduced later (on September 2013, while send was introduced in July 2012) and it allowed for deduplication with destination files that belong to read-only trees (subvolumes and snapshots). That means that having a send operation (either full or incremental) running in parallel with a deduplication that has the destination inode in one of the trees used by the send operation, can result in tree nodes and leaves getting freed and reused while send is using them. This problem is similar to the problem solved for the root nodes getting freed and reused when a snapshot is made against one tree that is currenly being used by a send operation, fixed in commits [1] and [2]. These commits explain in detail how the problem happens and the explanation is valid for any node or leaf that is not the root of a tree as well. This problem was also discussed and explained recently in a thread [3]. The problem is very easy to reproduce when using send with large trees (snapshots) and just a few concurrent deduplication operations that target files in the trees used by send. A stress test case is being sent for fstests that triggers the issue easily. The most common error to hit is the send ioctl return -EIO with the following messages in dmesg/syslog: [1631617.204075] BTRFS error (device sdc): did not find backref in send_root. inode=63292, offset=0, disk_byte=5228134400 found extent=5228134400 [1631633.251754] BTRFS error (device sdc): parent transid verify failed on 32243712 wanted 24 found 27 The first one is very easy to hit while the second one happens much less frequently, except for very large trees (in that test case, snapshots with 100000 files having large xattrs to get deep and wide trees). Less frequently, at least one BUG_ON can be hit: [1631742.130080] ------------[ cut here ]------------ [1631742.130625] kernel BUG at fs/btrfs/ctree.c:1806! [1631742.131188] invalid opcode: 0000 [#6] SMP DEBUG_PAGEALLOC PTI [1631742.131726] CPU: 1 PID: 13394 Comm: btrfs Tainted: G B D W 5.0.0-rc8-btrfs-next-45 #1 [1631742.132265] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [1631742.133399] RIP: 0010:read_node_slot+0x122/0x130 [btrfs] (...) [1631742.135061] RSP: 0018:ffffb530021ebaa0 EFLAGS: 00010246 [1631742.135615] RAX: ffff93ac8912e000 RBX: 000000000000009d RCX: 0000000000000002 [1631742.136173] RDX: 000000000000009d RSI: ffff93ac564b0d08 RDI: ffff93ad5b48c000 [1631742.136759] RBP: ffffb530021ebb7d R08: 0000000000000001 R09: ffffb530021ebb7d [1631742.137324] R10: ffffb530021eba70 R11: 0000000000000000 R12: ffff93ac87d0a708 [1631742.137900] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001 [1631742.138455] FS: 00007f4cdb1528c0(0000) GS:ffff93ad76a80000(0000) knlGS:0000000000000000 [1631742.139010] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [1631742.139568] CR2: 00007f5acb3d0420 CR3: 000000012be3e006 CR4: 00000000003606e0 [1631742.140131] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [1631742.140719] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [1631742.141272] Call Trace: [1631742.141826] ? do_raw_spin_unlock+0x49/0xc0 [1631742.142390] tree_advance+0x173/0x1d0 [btrfs] [1631742.142948] btrfs_compare_trees+0x268/0x690 [btrfs] [1631742.143533] ? process_extent+0x1070/0x1070 [btrfs] [1631742.144088] btrfs_ioctl_send+0x1037/0x1270 [btrfs] [1631742.144645] _btrfs_ioctl_send+0x80/0x110 [btrfs] [1631742.145161] ? trace_sched_stick_numa+0xe0/0xe0 [1631742.145685] btrfs_ioctl+0x13fe/0x3120 [btrfs] [1631742.146179] ? account_entity_enqueue+0xd3/0x100 [1631742.146662] ? reweight_entity+0x154/0x1a0 [1631742.147135] ? update_curr+0x20/0x2a0 [1631742.147593] ? check_preempt_wakeup+0x103/0x250 [1631742.148053] ? do_vfs_ioctl+0xa2/0x6f0 [1631742.148510] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [1631742.148942] do_vfs_ioctl+0xa2/0x6f0 [1631742.149361] ? __fget+0x113/0x200 [1631742.149767] ksys_ioctl+0x70/0x80 [1631742.150159] __x64_sys_ioctl+0x16/0x20 [1631742.150543] do_syscall_64+0x60/0x1b0 [1631742.150931] entry_SYSCALL_64_after_hwframe+0x49/0xbe [1631742.151326] RIP: 0033:0x7f4cd9f5add7 (...) [1631742.152509] RSP: 002b:00007ffe91017708 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [1631742.152892] RAX: ffffffffffffffda RBX: 0000000000000105 RCX: 00007f4cd9f5add7 [1631742.153268] RDX: 00007ffe91017790 RSI: 0000000040489426 RDI: 0000000000000007 [1631742.153633] RBP: 0000000000000007 R08: 00007f4cd9e79700 R09: 00007f4cd9e79700 [1631742.153999] R10: 00007f4cd9e799d0 R11: 0000000000000202 R12: 0000000000000003 [1631742.154365] R13: 0000555dfae53020 R14: 0000000000000000 R15: 0000000000000001 (...) [1631742.156696] ---[ end trace 5dac9f96dcc3fd6b ]--- That BUG_ON happens because while send is using a node, that node is COWed by a concurrent deduplication, gets freed and gets reused as a leaf (because a transaction commit happened in between), so when it attempts to read a slot from the extent buffer, at ctree.c:read_node_slot(), the extent buffer contents were wiped out and it now matches a leaf (which can even belong to some other tree now), hitting the BUG_ON(level == 0). Fix this concurrency issue by not allowing send and deduplication to run in parallel if both operate on the same readonly trees, returning EAGAIN to user space and logging an exlicit warning in dmesg/syslog. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=be6821f82c3cc36e026f5afd10249988852b35ea [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6f2f0b394b54e2b159ef969a0b5274e9bbf82ff2 [3] https://lore.kernel.org/linux-btrfs/CAL3q7H7iqSEEyFaEtpRZw3cp613y+4k2Q8b4W7mweR3tZA05bQ@mail.gmail.com/ CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22Btrfs: do not start a transaction at iterate_extent_inodes()Filipe Manana1-6/+12
commit bfc61c36260ca990937539cd648ede3cd749bc10 upstream. When finding out which inodes have references on a particular extent, done by backref.c:iterate_extent_inodes(), from the BTRFS_IOC_LOGICAL_INO (both v1 and v2) ioctl and from scrub we use the transaction join API to grab a reference on the currently running transaction, since in order to give accurate results we need to inspect the delayed references of the currently running transaction. However, if there is currently no running transaction, the join operation will create a new transaction. This is inefficient as the transaction will eventually be committed, doing unnecessary IO and introducing a potential point of failure that will lead to a transaction abort due to -ENOSPC, as recently reported [1]. That's because the join, creates the transaction but does not reserve any space, so when attempting to update the root item of the root passed to btrfs_join_transaction(), during the transaction commit, we can end up failling with -ENOSPC. Users of a join operation are supposed to actually do some filesystem changes and reserve space by some means, which is not the case of iterate_extent_inodes(), it is a read-only operation for all contextes from which it is called. The reported [1] -ENOSPC failure stack trace is the following: heisenberg kernel: ------------[ cut here ]------------ heisenberg kernel: BTRFS: Transaction aborted (error -28) heisenberg kernel: WARNING: CPU: 0 PID: 7137 at fs/btrfs/root-tree.c:136 btrfs_update_root+0x22b/0x320 [btrfs] (...) heisenberg kernel: CPU: 0 PID: 7137 Comm: btrfs-transacti Not tainted 4.19.0-4-amd64 #1 Debian 4.19.28-2 heisenberg kernel: Hardware name: FUJITSU LIFEBOOK U757/FJNB2A5, BIOS Version 1.21 03/19/2018 heisenberg kernel: RIP: 0010:btrfs_update_root+0x22b/0x320 [btrfs] (...) heisenberg kernel: RSP: 0018:ffffb5448828bd40 EFLAGS: 00010286 heisenberg kernel: RAX: 0000000000000000 RBX: ffff8ed56bccef50 RCX: 0000000000000006 heisenberg kernel: RDX: 0000000000000007 RSI: 0000000000000092 RDI: ffff8ed6bda166a0 heisenberg kernel: RBP: 00000000ffffffe4 R08: 00000000000003df R09: 0000000000000007 heisenberg kernel: R10: 0000000000000000 R11: 0000000000000001 R12: ffff8ed63396a078 heisenberg kernel: R13: ffff8ed092d7c800 R14: ffff8ed64f5db028 R15: ffff8ed6bd03d068 heisenberg kernel: FS: 0000000000000000(0000) GS:ffff8ed6bda00000(0000) knlGS:0000000000000000 heisenberg kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 heisenberg kernel: CR2: 00007f46f75f8000 CR3: 0000000310a0a002 CR4: 00000000003606f0 heisenberg kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 heisenberg kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 heisenberg kernel: Call Trace: heisenberg kernel: commit_fs_roots+0x166/0x1d0 [btrfs] heisenberg kernel: ? _cond_resched+0x15/0x30 heisenberg kernel: ? btrfs_run_delayed_refs+0xac/0x180 [btrfs] heisenberg kernel: btrfs_commit_transaction+0x2bd/0x870 [btrfs] heisenberg kernel: ? start_transaction+0x9d/0x3f0 [btrfs] heisenberg kernel: transaction_kthread+0x147/0x180 [btrfs] heisenberg kernel: ? btrfs_cleanup_transaction+0x530/0x530 [btrfs] heisenberg kernel: kthread+0x112/0x130 heisenberg kernel: ? kthread_bind+0x30/0x30 heisenberg kernel: ret_from_fork+0x35/0x40 heisenberg kernel: ---[ end trace 05de912e30e012d9 ]--- So fix that by using the attach API, which does not create a transaction when there is currently no running transaction. [1] https://lore.kernel.org/linux-btrfs/b2a668d7124f1d3e410367f587926f622b3f03a4.camel@scientia.net/ Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22Btrfs: do not start a transaction during fiemapFilipe Manana1-6/+10
commit 03628cdbc64db6262e50d0357960a4e9562676a1 upstream. During fiemap, for regular extents (non inline) we need to check if they are shared and if they are, set the shared bit. Checking if an extent is shared requires checking the delayed references of the currently running transaction, since some reference might have not yet hit the extent tree and be only in the in-memory delayed references. However we were using a transaction join for this, which creates a new transaction when there is no transaction currently running. That means that two more potential failures can happen: creating the transaction and committing it. Further, if no write activity is currently happening in the system, and fiemap calls keep being done, we end up creating and committing transactions that do nothing. In some extreme cases this can result in the commit of the transaction created by fiemap to fail with ENOSPC when updating the root item of a subvolume tree because a join does not reserve any space, leading to a trace like the following: heisenberg kernel: ------------[ cut here ]------------ heisenberg kernel: BTRFS: Transaction aborted (error -28) heisenberg kernel: WARNING: CPU: 0 PID: 7137 at fs/btrfs/root-tree.c:136 btrfs_update_root+0x22b/0x320 [btrfs] (...) heisenberg kernel: CPU: 0 PID: 7137 Comm: btrfs-transacti Not tainted 4.19.0-4-amd64 #1 Debian 4.19.28-2 heisenberg kernel: Hardware name: FUJITSU LIFEBOOK U757/FJNB2A5, BIOS Version 1.21 03/19/2018 heisenberg kernel: RIP: 0010:btrfs_update_root+0x22b/0x320 [btrfs] (...) heisenberg kernel: RSP: 0018:ffffb5448828bd40 EFLAGS: 00010286 heisenberg kernel: RAX: 0000000000000000 RBX: ffff8ed56bccef50 RCX: 0000000000000006 heisenberg kernel: RDX: 0000000000000007 RSI: 0000000000000092 RDI: ffff8ed6bda166a0 heisenberg kernel: RBP: 00000000ffffffe4 R08: 00000000000003df R09: 0000000000000007 heisenberg kernel: R10: 0000000000000000 R11: 0000000000000001 R12: ffff8ed63396a078 heisenberg kernel: R13: ffff8ed092d7c800 R14: ffff8ed64f5db028 R15: ffff8ed6bd03d068 heisenberg kernel: FS: 0000000000000000(0000) GS:ffff8ed6bda00000(0000) knlGS:0000000000000000 heisenberg kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 heisenberg kernel: CR2: 00007f46f75f8000 CR3: 0000000310a0a002 CR4: 00000000003606f0 heisenberg kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 heisenberg kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 heisenberg kernel: Call Trace: heisenberg kernel: commit_fs_roots+0x166/0x1d0 [btrfs] heisenberg kernel: ? _cond_resched+0x15/0x30 heisenberg kernel: ? btrfs_run_delayed_refs+0xac/0x180 [btrfs] heisenberg kernel: btrfs_commit_transaction+0x2bd/0x870 [btrfs] heisenberg kernel: ? start_transaction+0x9d/0x3f0 [btrfs] heisenberg kernel: transaction_kthread+0x147/0x180 [btrfs] heisenberg kernel: ? btrfs_cleanup_transaction+0x530/0x530 [btrfs] heisenberg kernel: kthread+0x112/0x130 heisenberg kernel: ? kthread_bind+0x30/0x30 heisenberg kernel: ret_from_fork+0x35/0x40 heisenberg kernel: ---[ end trace 05de912e30e012d9 ]--- Since fiemap (and btrfs_check_shared()) is a read-only operation, do not do a transaction join to avoid the overhead of creating a new transaction (if there is currently no running transaction) and introducing a potential point of failure when the new transaction gets committed, instead use a transaction attach to grab a handle for the currently running transaction if any. Reported-by: Christoph Anton Mitterer <calestyo@scientia.net> Link: https://lore.kernel.org/linux-btrfs/b2a668d7124f1d3e410367f587926f622b3f03a4.camel@scientia.net/ Fixes: afce772e87c36c ("btrfs: fix check_shared for fiemap ioctl") CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22Btrfs: send, flush dellaloc in order to avoid data lossFilipe Manana1-0/+36
commit 9f89d5de8631c7930898a601b6612e271aa2261c upstream. When we set a subvolume to read-only mode we do not flush dellaloc for any of its inodes (except if the filesystem is mounted with -o flushoncommit), since it does not affect correctness for any subsequent operations - except for a future send operation. The send operation will not be able to see the delalloc data since the respective file extent items, inode item updates, backreferences, etc, have not hit yet the subvolume and extent trees. Effectively this means data loss, since the send stream will not contain any data from existing delalloc. Another problem from this is that if the writeback starts and finishes while the send operation is in progress, we have the subvolume tree being being modified concurrently which can result in send failing unexpectedly with EIO or hitting runtime errors, assertion failures or hitting BUG_ONs, etc. Simple reproducer: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ btrfs subvolume create /mnt/sv $ xfs_io -f -c "pwrite -S 0xea 0 108K" /mnt/sv/foo $ btrfs property set /mnt/sv ro true $ btrfs send -f /tmp/send.stream /mnt/sv $ od -t x1 -A d /mnt/sv/foo 0000000 ea ea ea ea ea ea ea ea ea ea ea ea ea ea ea ea * 0110592 $ umount /mnt $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ btrfs receive -f /tmp/send.stream /mnt $ echo $? 0 $ od -t x1 -A d /mnt/sv/foo 0000000 # ---> empty file Since this a problem that affects send only, fix it in send by flushing dellaloc for all the roots used by the send operation before send starts to process the commit roots. This is a problem that affects send since it was introduced (commit 31db9f7c23fbf7 ("Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receive")) but backporting it to older kernels has some dependencies: - For kernels between 3.19 and 4.20, it depends on commit 3cd24c698004d2 ("btrfs: use tagged writepage to mitigate livelock of snapshot") because the function btrfs_start_delalloc_snapshot() does not exist before that commit. So one has to either pick that commit or replace the calls to btrfs_start_delalloc_snapshot() in this patch with calls to btrfs_start_delalloc_inodes(). - For kernels older than 3.19 it also requires commit e5fa8f865b3324 ("Btrfs: ensure send always works on roots without orphans") because it depends on the function ensure_commit_roots_uptodate() which that commits introduced. - No dependencies for 5.0+ kernels. A test case for fstests follows soon. CC: stable@vger.kernel.org # 3.19+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22btrfs: Honour FITRIM range constraints during free space trimNikolay Borisov1-6/+19
commit c2d1b3aae33605a61cbab445d8ae1c708ccd2698 upstream. Up until now trimming the freespace was done irrespective of what the arguments of the FITRIM ioctl were. For example fstrim's -o/-l arguments will be entirely ignored. Fix it by correctly handling those paramter. This requires breaking if the found freespace extent is after the end of the passed range as well as completing trim after trimming fstrim_range::len bytes. Fixes: 499f377f49f0 ("btrfs: iterate over unused chunk space in FITRIM") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22btrfs: Correctly free extent buffer in case btree_read_extent_buffer_pages failsNikolay Borisov1-6/+11
commit 537f38f019fa0b762dbb4c0fc95d7fcce9db8e2d upstream. If a an eb fails to be read for whatever reason - it's corrupted on disk and parent transid/key validations fail or IO for eb pages fail then this buffer must be removed from the buffer cache. Currently the code calls free_extent_buffer if an error occurs. Unfortunately this doesn't achieve the desired behavior since btrfs_find_create_tree_block returns with eb->refs == 2. On the other hand free_extent_buffer will only decrement the refs once leaving it added to the buffer cache radix tree. This enables later code to look up the buffer from the cache and utilize it potentially leading to a crash. The correct way to free the buffer is call free_extent_buffer_stale. This function will correctly call atomic_dec explicitly for the buffer and subsequently call release_extent_buffer which will decrement the final reference thus correctly remove the invalid buffer from buffer cache. This change affects only newly allocated buffers since they have eb->refs == 2. Link: https://bugzilla.kernel.org/show_bug.cgi?id=202755 Reported-by: Jungyeon <jungyeon@gatech.edu> CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22btrfs: Check the first key and level for cached extent bufferQu Wenruo3-5/+18
commit 448de471cd4cab0cedd15770082567a69a784a11 upstream. [BUG] When reading a file from a fuzzed image, kernel can panic like: BTRFS warning (device loop0): csum failed root 5 ino 270 off 0 csum 0x98f94189 expected csum 0x00000000 mirror 1 assertion failed: !memcmp_extent_buffer(b, &disk_key, offsetof(struct btrfs_leaf, items[0].key), sizeof(disk_key)), file: fs/btrfs/ctree.c, line: 2544 ------------[ cut here ]------------ kernel BUG at fs/btrfs/ctree.h:3500! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:btrfs_search_slot.cold.24+0x61/0x63 [btrfs] Call Trace: btrfs_lookup_csum+0x52/0x150 [btrfs] __btrfs_lookup_bio_sums+0x209/0x640 [btrfs] btrfs_submit_bio_hook+0x103/0x170 [btrfs] submit_one_bio+0x59/0x80 [btrfs] extent_read_full_page+0x58/0x80 [btrfs] generic_file_read_iter+0x2f6/0x9d0 __vfs_read+0x14d/0x1a0 vfs_read+0x8d/0x140 ksys_read+0x52/0xc0 do_syscall_64+0x60/0x210 entry_SYSCALL_64_after_hwframe+0x49/0xbe [CAUSE] The fuzzed image has a corrupted leaf whose first key doesn't match its parent: checksum tree key (CSUM_TREE ROOT_ITEM 0) node 29741056 level 1 items 14 free 107 generation 19 owner CSUM_TREE fs uuid 3381d111-94a3-4ac7-8f39-611bbbdab7e6 chunk uuid 9af1c3c7-2af5-488b-8553-530bd515f14c ... key (EXTENT_CSUM EXTENT_CSUM 79691776) block 29761536 gen 19 leaf 29761536 items 1 free space 1726 generation 19 owner CSUM_TREE leaf 29761536 flags 0x1(WRITTEN) backref revision 1 fs uuid 3381d111-94a3-4ac7-8f39-611bbbdab7e6 chunk uuid 9af1c3c7-2af5-488b-8553-530bd515f14c item 0 key (EXTENT_CSUM EXTENT_CSUM 8798638964736) itemoff 1751 itemsize 2244 range start 8798638964736 end 8798641262592 length 2297856 When reading the above tree block, we have extent_buffer->refs = 2 in the context: - initial one from __alloc_extent_buffer() alloc_extent_buffer() |- __alloc_extent_buffer() |- atomic_set(&eb->refs, 1) - one being added to fs_info->buffer_radix alloc_extent_buffer() |- check_buffer_tree_ref() |- atomic_inc(&eb->refs) So if even we call free_extent_buffer() in read_tree_block or other similar situation, we only decrease the refs by 1, it doesn't reach 0 and won't be freed right now. The staled eb and its corrupted content will still be kept cached. Furthermore, we have several extra cases where we either don't do first key check or the check is not proper for all callers: - scrub We just don't have first key in this context. - shared tree block One tree block can be shared by several snapshot/subvolume trees. In that case, the first key check for one subvolume doesn't apply to another. So for the above reasons, a corrupted extent buffer can sneak into the buffer cache. [FIX] Call verify_level_key in read_block_for_search to do another verification. For that purpose the function is exported. Due to above reasons, although we can free corrupted extent buffer from cache, we still need the check in read_block_for_search(), for scrub and shared tree blocks. Link: https://bugzilla.kernel.org/show_bug.cgi?id=202755 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202757 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202759 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202761 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202767 Link: https://bugzilla.kernel.org/show_bug.cgi?id=202769 Reported-by: Yoon Jungyeon <jungyeon@gatech.edu> CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ext4: fix ext4_show_options for file systems w/o journalDebabrata Banerjee1-1/+1
commit 50b29d8f033a7c88c5bc011abc2068b1691ab755 upstream. Instead of removing EXT4_MOUNT_JOURNAL_CHECKSUM from s_def_mount_opt as I assume was intended, all other options were blown away leading to _ext4_show_options() output being incorrect. Fixes: 1e381f60dad9 ("ext4: do not allow journal_opts for fs w/o journal") Signed-off-by: Debabrata Banerjee <dbanerje@akamai.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ext4: actually request zeroing of inode table after growKirill Tkhai1-1/+1
commit 310a997fd74de778b9a4848a64be9cda9f18764a upstream. It is never possible, that number of block groups decreases, since only online grow is supported. But after a growing occured, we have to zero inode tables for just created new block groups. Fixes: 19c5246d2516 ("ext4: add new online resize interface") Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ext4: fix use-after-free race with debug_want_extra_isizeBarret Rhoden1-24/+34
commit 7bc04c5c2cc467c5b40f2b03ba08da174a0d5fa7 upstream. When remounting with debug_want_extra_isize, we were not performing the same checks that we do during a normal mount. That allowed us to set a value for s_want_extra_isize that reached outside the s_inode_size. Fixes: e2b911c53584 ("ext4: clean up feature test macros with predicate functions") Reported-by: syzbot+f584efa0ac7213c226b7@syzkaller.appspotmail.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Barret Rhoden <brho@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ext4: avoid drop reference to iloc.bh twicePan Bian1-0/+1
commit 8c380ab4b7b59c0c602743810be1b712514eaebc upstream. The reference to iloc.bh has been dropped in ext4_mark_iloc_dirty. However, the reference is dropped again if error occurs during ext4_handle_dirty_metadata, which may result in use-after-free bugs. Fixes: fb265c9cb49e("ext4: add ext4_sb_bread() to disambiguate ENOMEM cases") Signed-off-by: Pan Bian <bianpan2016@163.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ext4: ignore e_value_offs for xattrs with value-in-ea-inodeTheodore Ts'o1-1/+1
commit e5d01196c0428a206f307e9ee5f6842964098ff0 upstream. In other places in fs/ext4/xattr.c, if e_value_inum is non-zero, the code ignores the value in e_value_offs. The e_value_offs *should* be zero, but we shouldn't depend upon it, since it might not be true in a corrupted/fuzzed file system. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202897 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202877 Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ext4: make sanity check in mballoc more strictJan Kara1-1/+1
commit 31562b954b60f02acb91b7349dc6432d3f8c3c5f upstream. The sanity check in mb_find_extent() only checked that returned extent does not extend past blocksize * 8, however it should not extend past EXT4_CLUSTERS_PER_GROUP(sb). This can happen when clusters_per_group < blocksize * 8 and the tail of the bitmap is not properly filled by 1s which happened e.g. when ancient kernels have grown the filesystem. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22jbd2: check superblock mapped prior to committingJiufei Xue1-0/+4
commit 742b06b5628f2cd23cb51a034cb54dc33c6162c5 upstream. We hit a BUG at fs/buffer.c:3057 if we detached the nbd device before unmounting ext4 filesystem. The typical chain of events leading to the BUG: jbd2_write_superblock submit_bh submit_bh_wbc BUG_ON(!buffer_mapped(bh)); The block device is removed and all the pages are invalidated. JBD2 was trying to write journal superblock to the block device which is no longer present. Fix this by checking the journal superblock's buffer head prior to submitting. Reported-by: Eric Ren <renzhen@linux.alibaba.com> Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22ocfs2: fix ocfs2 read inode data panic in ocfs2_igetShuning Zhang1-1/+29
commit e091eab028f9253eac5c04f9141bbc9d170acab3 upstream. In some cases, ocfs2_iget() reads the data of inode, which has been deleted for some reason. That will make the system panic. So We should judge whether this inode has been deleted, and tell the caller that the inode is a bad inode. For example, the ocfs2 is used as the backed of nfs, and the client is nfsv3. This issue can be reproduced by the following steps. on the nfs server side, ..../patha/pathb Step 1: The process A was scheduled before calling the function fh_verify. Step 2: The process B is removing the 'pathb', and just completed the call to function dput. Then the dentry of 'pathb' has been deleted from the dcache, and all ancestors have been deleted also. The relationship of dentry and inode was deleted through the function hlist_del_init. The following is the call stack. dentry_iput->hlist_del_init(&dentry->d_u.d_alias) At this time, the inode is still in the dcache. Step 3: The process A call the function ocfs2_get_dentry, which get the inode from dcache. Then the refcount of inode is 1. The following is the call stack. nfsd3_proc_getacl->fh_verify->exportfs_decode_fh->fh_to_dentry(ocfs2_get_dentry) Step 4: Dirty pages are flushed by bdi threads. So the inode of 'patha' is evicted, and this directory was deleted. But the inode of 'pathb' can't be evicted, because the refcount of the inode was 1. Step 5: The process A keep running, and call the function reconnect_path(in exportfs_decode_fh), which call function ocfs2_get_parent of ocfs2. Get the block number of parent directory(patha) by the name of ... Then read the data from disk by the block number. But this inode has been deleted, so the system panic. Process A Process B 1. in nfsd3_proc_getacl | 2. | dput 3. fh_to_dentry(ocfs2_get_dentry) | 4. bdi flush dirty cache | 5. ocfs2_iget | [283465.542049] OCFS2: ERROR (device sdp): ocfs2_validate_inode_block: Invalid dinode #580640: OCFS2_VALID_FL not set [283465.545490] Kernel panic - not syncing: OCFS2: (device sdp): panic forced after error [283465.546889] CPU: 5 PID: 12416 Comm: nfsd Tainted: G W 4.1.12-124.18.6.el6uek.bug28762940v3.x86_64 #2 [283465.548382] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 09/21/2015 [283465.549657] 0000000000000000 ffff8800a56fb7b8 ffffffff816e839c ffffffffa0514758 [283465.550392] 000000000008dc20 ffff8800a56fb838 ffffffff816e62d3 0000000000000008 [283465.551056] ffff880000000010 ffff8800a56fb848 ffff8800a56fb7e8 ffff88005df9f000 [283465.551710] Call Trace: [283465.552516] [<ffffffff816e839c>] dump_stack+0x63/0x81 [283465.553291] [<ffffffff816e62d3>] panic+0xcb/0x21b [283465.554037] [<ffffffffa04e66b0>] ocfs2_handle_error+0xf0/0xf0 [ocfs2] [283465.554882] [<ffffffffa04e7737>] __ocfs2_error+0x67/0x70 [ocfs2] [283465.555768] [<ffffffffa049c0f9>] ocfs2_validate_inode_block+0x229/0x230 [ocfs2] [283465.556683] [<ffffffffa047bcbc>] ocfs2_read_blocks+0x46c/0x7b0 [ocfs2] [283465.557408] [<ffffffffa049bed0>] ? ocfs2_inode_cache_io_unlock+0x20/0x20 [ocfs2] [283465.557973] [<ffffffffa049f0eb>] ocfs2_read_inode_block_full+0x3b/0x60 [ocfs2] [283465.558525] [<ffffffffa049f5ba>] ocfs2_iget+0x4aa/0x880 [ocfs2] [283465.559082] [<ffffffffa049146e>] ocfs2_get_parent+0x9e/0x220 [ocfs2] [283465.559622] [<ffffffff81297c05>] reconnect_path+0xb5/0x300 [283465.560156] [<ffffffff81297f46>] exportfs_decode_fh+0xf6/0x2b0 [283465.560708] [<ffffffffa062faf0>] ? nfsd_proc_getattr+0xa0/0xa0 [nfsd] [283465.561262] [<ffffffff810a8196>] ? prepare_creds+0x26/0x110 [283465.561932] [<ffffffffa0630860>] fh_verify+0x350/0x660 [nfsd] [283465.562862] [<ffffffffa0637804>] ? nfsd_cache_lookup+0x44/0x630 [nfsd] [283465.563697] [<ffffffffa063a8b9>] nfsd3_proc_getattr+0x69/0xf0 [nfsd] [283465.564510] [<ffffffffa062cf60>] nfsd_dispatch+0xe0/0x290 [nfsd] [283465.565358] [<ffffffffa05eb892>] ? svc_tcp_adjust_wspace+0x12/0x30 [sunrpc] [283465.566272] [<ffffffffa05ea652>] svc_process_common+0x412/0x6a0 [sunrpc] [283465.567155] [<ffffffffa05eaa03>] svc_process+0x123/0x210 [sunrpc] [283465.568020] [<ffffffffa062c90f>] nfsd+0xff/0x170 [nfsd] [283465.568962] [<ffffffffa062c810>] ? nfsd_destroy+0x80/0x80 [nfsd] [283465.570112] [<ffffffff810a622b>] kthread+0xcb/0xf0 [283465.571099] [<ffffffff810a6160>] ? kthread_create_on_node+0x180/0x180 [283465.572114] [<ffffffff816f11b8>] ret_from_fork+0x58/0x90 [283465.573156] [<ffffffff810a6160>] ? kthread_create_on_node+0x180/0x180 Link: http://lkml.kernel.org/r/1554185919-3010-1-git-send-email-sunny.s.zhang@oracle.com Signed-off-by: Shuning Zhang <sunny.s.zhang@oracle.com> Reviewed-by: Joseph Qi <jiangqi903@gmail.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: piaojun <piaojun@huawei.com> Cc: "Gang He" <ghe@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22hugetlb: use same fault hash key for shared and private mappingsMike Kravetz1-5/+2
commit 1b426bac66e6cc83c9f2d92b96e4e72acf43419a upstream. hugetlb uses a fault mutex hash table to prevent page faults of the same pages concurrently. The key for shared and private mappings is different. Shared keys off address_space and file index. Private keys off mm and virtual address. Consider a private mappings of a populated hugetlbfs file. A fault will map the page from the file and if needed do a COW to map a writable page. Hugetlbfs hole punch uses the fault mutex to prevent mappings of file pages. It uses the address_space file index key. However, private mappings will use a different key and could race with this code to map the file page. This causes problems (BUG) for the page cache remove code as it expects the page to be unmapped. A sample stack is: page dumped because: VM_BUG_ON_PAGE(page_mapped(page)) kernel BUG at mm/filemap.c:169! ... RIP: 0010:unaccount_page_cache_page+0x1b8/0x200 ... Call Trace: __delete_from_page_cache+0x39/0x220 delete_from_page_cache+0x45/0x70 remove_inode_hugepages+0x13c/0x380 ? __add_to_page_cache_locked+0x162/0x380 hugetlbfs_fallocate+0x403/0x540 ? _cond_resched+0x15/0x30 ? __inode_security_revalidate+0x5d/0x70 ? selinux_file_permission+0x100/0x130 vfs_fallocate+0x13f/0x270 ksys_fallocate+0x3c/0x80 __x64_sys_fallocate+0x1a/0x20 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 There seems to be another potential COW issue/race with this approach of different private and shared keys as noted in commit 8382d914ebf7 ("mm, hugetlb: improve page-fault scalability"). Since every hugetlb mapping (even anon and private) is actually a file mapping, just use the address_space index key for all mappings. This results in potentially more hash collisions. However, this should not be the common case. Link: http://lkml.kernel.org/r/20190328234704.27083-3-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20190412165235.t4sscoujczfhuiyt@linux-r8p5 Fixes: b5cec28d36f5 ("hugetlbfs: truncate_hugepages() takes a range of pages") Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Davidlohr Bueso <dbueso@suse.de> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22mm/huge_memory: fix vmf_insert_pfn_{pmd, pud}() crash, handle unaligned ↵Dan Williams1-4/+2
addresses commit fce86ff5802bac3a7b19db171aa1949ef9caac31 upstream. Starting with c6f3c5ee40c1 ("mm/huge_memory.c: fix modifying of page protection by insert_pfn_pmd()") vmf_insert_pfn_pmd() internally calls pmdp_set_access_flags(). That helper enforces a pmd aligned @address argument via VM_BUG_ON() assertion. Update the implementation to take a 'struct vm_fault' argument directly and apply the address alignment fixup internally to fix crash signatures like: kernel BUG at arch/x86/mm/pgtable.c:515! invalid opcode: 0000 [#1] SMP NOPTI CPU: 51 PID: 43713 Comm: java Tainted: G OE 4.19.35 #1 [..] RIP: 0010:pmdp_set_access_flags+0x48/0x50 [..] Call Trace: vmf_insert_pfn_pmd+0x198/0x350 dax_iomap_fault+0xe82/0x1190 ext4_dax_huge_fault+0x103/0x1f0 ? __switch_to_asm+0x40/0x70 __handle_mm_fault+0x3f6/0x1370 ? __switch_to_asm+0x34/0x70 ? __switch_to_asm+0x40/0x70 handle_mm_fault+0xda/0x200 __do_page_fault+0x249/0x4f0 do_page_fault+0x32/0x110 ? page_fault+0x8/0x30 page_fault+0x1e/0x30 Link: http://lkml.kernel.org/r/155741946350.372037.11148198430068238140.stgit@dwillia2-desk3.amr.corp.intel.com Fixes: c6f3c5ee40c1 ("mm/huge_memory.c: fix modifying of page protection by insert_pfn_pmd()") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Piotr Balcer <piotr.balcer@intel.com> Tested-by: Yan Ma <yan.ma@intel.com> Tested-by: Pankaj Gupta <pagupta@redhat.com> Reviewed-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Chandan Rajendra <chandan@linux.ibm.com> Cc: Souptick Joarder <jrdr.linux@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-16f2fs: Fix use of number of devicesDamien Le Moal5-15/+32
commit 0916878da355650d7e77104a7ac0fa1784eca852 upstream. For a single device mount using a zoned block device, the zone information for the device is stored in the sbi->devs single entry array and sbi->s_ndevs is set to 1. This differs from a single device mount using a regular block device which does not allocate sbi->devs and sets sbi->s_ndevs to 0. However, sbi->s_devs == 0 condition is used throughout the code to differentiate a single device mount from a multi-device mount where sbi->s_ndevs is always larger than 1. This results in problems with single zoned block device volumes as these are treated as multi-device mounts but do not have the start_blk and end_blk information set. One of the problem observed is skipping of zone discard issuing resulting in write commands being issued to full zones or unaligned to a zone write pointer. Fix this problem by simply treating the cases sbi->s_ndevs == 0 (single regular block device mount) and sbi->s_ndevs == 1 (single zoned block device mount) in the same manner. This is done by introducing the helper function f2fs_is_multi_device() and using this helper in place of direct tests of sbi->s_ndevs value, improving code readability. Fixes: 7bb3a371d199 ("f2fs: Fix zoned block device support") Cc: <stable@vger.kernel.org> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-16kernfs: fix barrier usage in __kernfs_new_node()Andrea Parri1-3/+2
commit 998267900cee901c5d1dfa029a6304d00acbc29f upstream. smp_mb__before_atomic() can not be applied to atomic_set(). Remove the barrier and rely on RELEASE synchronization. Fixes: ba16b2846a8c6 ("kernfs: add an API to get kernfs node from inode number") Cc: stable@vger.kernel.org Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-05Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds3-8/+8
Pull vfs fixes from Al Viro: - a couple of ->i_link use-after-free fixes - regression fix for wrong errno on absent device name in mount(2) (this cycle stuff) - ancient UFS braino in large GID handling on Solaris UFS images (bogus cut'n'paste from large UID handling; wrong field checked to decide whether we should look at old (16bit) or new (32bit) field) * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ufs: fix braino in ufs_get_inode_gid() for solaris UFS flavour Abort file_remove_privs() for non-reg. files [fix] get rid of checking for absent device name in vfs_get_tree() apparmorfs: fix use-after-free on symlink traversal securityfs: fix use-after-free on symlink traversal
2019-05-02Merge tag 'for-linus-20190502' of git://git.kernel.dk/linux-blockLinus Torvalds2-92/+160
Pull io_uring fixes from Jens Axboe: "This is mostly io_uring fixes/tweaks. Most of these were actually done in time for the last -rc, but I wanted to ensure that everything tested out great before including them. The code delta looks larger than it really is, as it's mostly just comment additions/changes. Outside of the comment additions/changes, this is mostly removal of unnecessary barriers. In all, this pull request contains: - Tweak to how we handle errors at submission time. We now post a completion event if the error occurs on behalf of an sqe, instead of returning it through the system call. If the error happens outside of a specific sqe, we return the error through the system call. This makes it nicer to use and makes the "normal" use case behave the same as the offload cases. (me) - Fix for a missing req reference drop from async context (me) - If an sqe is submitted with RWF_NOWAIT, don't punt it to async context. Return -EAGAIN directly, instead of using it as a hint to do async punt. (Stefan) - Fix notes on barriers (Stefan) - Remove unnecessary barriers (Stefan) - Fix potential double free of memory in setup error (Mark) - Further improve sq poll CPU validation (Mark) - Fix page allocation warning and leak on buffer registration error (Mark) - Fix iov_iter_type() for new no-ref flag (Ming) - Fix a case where dio doesn't honor bio no-page-ref (Ming)" * tag 'for-linus-20190502' of git://git.kernel.dk/linux-block: io_uring: avoid page allocation warnings iov_iter: fix iov_iter_type block: fix handling for BIO_NO_PAGE_REF io_uring: drop req submit reference always in async punt io_uring: free allocated io_memory once io_uring: fix SQPOLL cpu validation io_uring: have submission side sqe errors post a cqe io_uring: remove unnecessary barrier after unsetting IORING_SQ_NEED_WAKEUP io_uring: remove unnecessary barrier after incrementing dropped counter io_uring: remove unnecessary barrier before reading SQ tail io_uring: remove unnecessary barrier after updating SQ head io_uring: remove unnecessary barrier before reading cq head io_uring: remove unnecessary barrier before wq_has_sleeper io_uring: fix notes on barriers io_uring: fix handling SQEs requesting NOWAIT
2019-05-02ufs: fix braino in ufs_get_inode_gid() for solaris UFS flavourAl Viro1-1/+1
To choose whether to pick the GID from the old (16bit) or new (32bit) field, we should check if the old gid field is set to 0xffff. Mainline checks the old *UID* field instead - cut'n'paste from the corresponding code in ufs_get_inode_uid(). Fixes: 252e211e90ce Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-01gcc-9: don't warn about uninitialized btrfs extent_type variableLinus Torvalds1-1/+1
The 'extent_type' variable does seem to be reliably initialized, but it's _very_ non-obvious, since there's a "goto next" case that jumps over the normal initialization. That will then always trigger the "start >= extent_end" test, which will end up never falling through to the use of that variable. But the code is certainly not obvious, and the compiler warning looks reasonable. Make 'extent_type' an int, and initialize it to an invalid negative value, which seems to be the common pattern in other places. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-01io_uring: avoid page allocation warningsMark Rutland1-8/+9
In io_sqe_buffer_register() we allocate a number of arrays based on the iov_len from the user-provided iov. While we limit iov_len to SZ_1G, we can still attempt to allocate arrays exceeding MAX_ORDER. On a 64-bit system with 4KiB pages, for an iov where iov_base = 0x10 and iov_len = SZ_1G, we'll calculate that nr_pages = 262145. When we try to allocate a corresponding array of (16-byte) bio_vecs, requiring 4194320 bytes, which is greater than 4MiB. This results in SLUB warning that we're trying to allocate greater than MAX_ORDER, and failing the allocation. Avoid this by using kvmalloc() for allocations dependent on the user-provided iov_len. At the same time, fix a leak of imu->bvec when registration fails. Full splat from before this patch: WARNING: CPU: 1 PID: 2314 at mm/page_alloc.c:4595 __alloc_pages_nodemask+0x7ac/0x2938 mm/page_alloc.c:4595 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 2314 Comm: syz-executor326 Not tainted 5.1.0-rc7-dirty #4 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x0/0x2f0 include/linux/compiler.h:193 show_stack+0x20/0x30 arch/arm64/kernel/traps.c:158 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x110/0x190 lib/dump_stack.c:113 panic+0x384/0x68c kernel/panic.c:214 __warn+0x2bc/0x2c0 kernel/panic.c:571 report_bug+0x228/0x2d8 lib/bug.c:186 bug_handler+0xa0/0x1a0 arch/arm64/kernel/traps.c:956 call_break_hook arch/arm64/kernel/debug-monitors.c:301 [inline] brk_handler+0x1d4/0x388 arch/arm64/kernel/debug-monitors.c:316 do_debug_exception+0x1a0/0x468 arch/arm64/mm/fault.c:831 el1_dbg+0x18/0x8c __alloc_pages_nodemask+0x7ac/0x2938 mm/page_alloc.c:4595 alloc_pages_current+0x164/0x278 mm/mempolicy.c:2132 alloc_pages include/linux/gfp.h:509 [inline] kmalloc_order+0x20/0x50 mm/slab_common.c:1231 kmalloc_order_trace+0x30/0x2b0 mm/slab_common.c:1243 kmalloc_large include/linux/slab.h:480 [inline] __kmalloc+0x3dc/0x4f0 mm/slub.c:3791 kmalloc_array include/linux/slab.h:670 [inline] io_sqe_buffer_register fs/io_uring.c:2472 [inline] __io_uring_register fs/io_uring.c:2962 [inline] __do_sys_io_uring_register fs/io_uring.c:3008 [inline] __se_sys_io_uring_register fs/io_uring.c:2990 [inline] __arm64_sys_io_uring_register+0x9e0/0x1bc8 fs/io_uring.c:2990 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall arch/arm64/kernel/syscall.c:47 [inline] el0_svc_common.constprop.0+0x148/0x2e0 arch/arm64/kernel/syscall.c:83 el0_svc_handler+0xdc/0x100 arch/arm64/kernel/syscall.c:129 el0_svc+0x8/0xc arch/arm64/kernel/entry.S:948 SMP: stopping secondary CPUs Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled CPU features: 0x002,23000438 Memory Limit: none Rebooting in 1 seconds.. Fixes: edafccee56ff3167 ("io_uring: add support for pre-mapped user IO buffers") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-fsdevel@vger.kernel.org Cc: linux-block@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-05-01block: fix handling for BIO_NO_PAGE_REFMing Lei1-1/+2
Commit 399254aaf489211 ("block: add BIO_NO_PAGE_REF flag") introduces BIO_NO_PAGE_REF, and once this flag is set for one bio, all pages in the bio won't be get/put during IO. However, if one bio is submitted via __blkdev_direct_IO_simple(), even though BIO_NO_PAGE_REF is set, pages still may be put. Fixes this issue by avoiding to put pages if BIO_NO_PAGE_REF is set. Fixes: 399254aaf489211 ("block: add BIO_NO_PAGE_REF flag") Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-05-01io_uring: drop req submit reference always in async puntJens Axboe1-3/+4
If we don't end up actually calling submit in io_sq_wq_submit_work(), we still need to drop the submit reference to the request. If we don't, then we can leak the request. This can happen if we race with ring shutdown while flushing the workqueue for requests that require use of the mm_struct. Fixes: e65ef56db494 ("io_uring: use regular request ref counts") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-05-01io_uring: free allocated io_memory onceMark Rutland1-8/+7
If io_allocate_scq_urings() fails to allocate an sq_* region, it will call io_mem_free() for any previously allocated regions, but leave dangling pointers to these regions in the ctx. Any regions which have not yet been allocated are left NULL. Note that when returning -EOVERFLOW, the previously allocated sq_ring is not freed, which appears to be an unintentional leak. When io_allocate_scq_urings() fails, io_uring_create() will call io_ring_ctx_wait_and_kill(), which calls io_mem_free() on all the sq_* regions, assuming the pointers are valid and not NULL. This can result in pages being freed multiple times, which has been observed to corrupt the page state, leading to subsequent fun. This can also result in virt_to_page() on NULL, resulting in the use of bogus page addresses, and yet more subsequent fun. The latter can be detected with CONFIG_DEBUG_VIRTUAL on arm64. Adding a cleanup path to io_allocate_scq_urings() complicates the logic, so let's leave it to io_ring_ctx_free() to consistently free these pointers, and simplify the io_allocate_scq_urings() error paths. Full splats from before this patch below. Note that the pointer logged by the DEBUG_VIRTUAL "non-linear address" warning has been hashed, and is actually NULL. [ 26.098129] page:ffff80000e949a00 count:0 mapcount:-128 mapping:0000000000000000 index:0x0 [ 26.102976] flags: 0x63fffc000000() [ 26.104373] raw: 000063fffc000000 ffff80000e86c188 ffff80000ea3df08 0000000000000000 [ 26.108917] raw: 0000000000000000 0000000000000001 00000000ffffff7f 0000000000000000 [ 26.137235] page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0) [ 26.143960] ------------[ cut here ]------------ [ 26.146020] kernel BUG at include/linux/mm.h:547! [ 26.147586] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [ 26.149163] Modules linked in: [ 26.150287] Process syz-executor.21 (pid: 20204, stack limit = 0x000000000e9cefeb) [ 26.153307] CPU: 2 PID: 20204 Comm: syz-executor.21 Not tainted 5.1.0-rc7-00004-g7d30b2ea43d6 #18 [ 26.156566] Hardware name: linux,dummy-virt (DT) [ 26.158089] pstate: 40400005 (nZcv daif +PAN -UAO) [ 26.159869] pc : io_mem_free+0x9c/0xa8 [ 26.161436] lr : io_mem_free+0x9c/0xa8 [ 26.162720] sp : ffff000013003d60 [ 26.164048] x29: ffff000013003d60 x28: ffff800025048040 [ 26.165804] x27: 0000000000000000 x26: ffff800025048040 [ 26.167352] x25: 00000000000000c0 x24: ffff0000112c2820 [ 26.169682] x23: 0000000000000000 x22: 0000000020000080 [ 26.171899] x21: ffff80002143b418 x20: ffff80002143b400 [ 26.174236] x19: ffff80002143b280 x18: 0000000000000000 [ 26.176607] x17: 0000000000000000 x16: 0000000000000000 [ 26.178997] x15: 0000000000000000 x14: 0000000000000000 [ 26.181508] x13: 00009178a5e077b2 x12: 0000000000000001 [ 26.183863] x11: 0000000000000000 x10: 0000000000000980 [ 26.186437] x9 : ffff000013003a80 x8 : ffff800025048a20 [ 26.189006] x7 : ffff8000250481c0 x6 : ffff80002ffe9118 [ 26.191359] x5 : ffff80002ffe9118 x4 : 0000000000000000 [ 26.193863] x3 : ffff80002ffefe98 x2 : 44c06ddd107d1f00 [ 26.196642] x1 : 0000000000000000 x0 : 000000000000003e [ 26.198892] Call trace: [ 26.199893] io_mem_free+0x9c/0xa8 [ 26.201155] io_ring_ctx_wait_and_kill+0xec/0x180 [ 26.202688] io_uring_setup+0x6c4/0x6f0 [ 26.204091] __arm64_sys_io_uring_setup+0x18/0x20 [ 26.205576] el0_svc_common.constprop.0+0x7c/0xe8 [ 26.207186] el0_svc_handler+0x28/0x78 [ 26.208389] el0_svc+0x8/0xc [ 26.209408] Code: aa0203e0 d0006861 9133a021 97fcdc3c (d4210000) [ 26.211995] ---[ end trace bdb81cd43a21e50d ]--- [ 81.770626] ------------[ cut here ]------------ [ 81.825015] virt_to_phys used for non-linear address: 000000000d42f2c7 ( (null)) [ 81.827860] WARNING: CPU: 1 PID: 30171 at arch/arm64/mm/physaddr.c:15 __virt_to_phys+0x48/0x68 [ 81.831202] Modules linked in: [ 81.832212] CPU: 1 PID: 30171 Comm: syz-executor.20 Not tainted 5.1.0-rc7-00004-g7d30b2ea43d6 #19 [ 81.835616] Hardware name: linux,dummy-virt (DT) [ 81.836863] pstate: 60400005 (nZCv daif +PAN -UAO) [ 81.838727] pc : __virt_to_phys+0x48/0x68 [ 81.840572] lr : __virt_to_phys+0x48/0x68 [ 81.842264] sp : ffff80002cf67c70 [ 81.843858] x29: ffff80002cf67c70 x28: ffff800014358e18 [ 81.846463] x27: 0000000000000000 x26: 0000000020000080 [ 81.849148] x25: 0000000000000000 x24: ffff80001bb01f40 [ 81.851986] x23: ffff200011db06c8 x22: ffff2000127e3c60 [ 81.854351] x21: ffff800014358cc0 x20: ffff800014358d98 [ 81.856711] x19: 0000000000000000 x18: 0000000000000000 [ 81.859132] x17: 0000000000000000 x16: 0000000000000000 [ 81.861586] x15: 0000000000000000 x14: 0000000000000000 [ 81.863905] x13: 0000000000000000 x12: ffff1000037603e9 [ 81.866226] x11: 1ffff000037603e8 x10: 0000000000000980 [ 81.868776] x9 : ffff80002cf67840 x8 : ffff80001bb02920 [ 81.873272] x7 : ffff1000037603e9 x6 : ffff80001bb01f47 [ 81.875266] x5 : ffff1000037603e9 x4 : dfff200000000000 [ 81.876875] x3 : ffff200010087528 x2 : ffff1000059ecf58 [ 81.878751] x1 : 44c06ddd107d1f00 x0 : 0000000000000000 [ 81.880453] Call trace: [ 81.881164] __virt_to_phys+0x48/0x68 [ 81.882919] io_mem_free+0x18/0x110 [ 81.886585] io_ring_ctx_wait_and_kill+0x13c/0x1f0 [ 81.891212] io_uring_setup+0xa60/0xad0 [ 81.892881] __arm64_sys_io_uring_setup+0x2c/0x38 [ 81.894398] el0_svc_common.constprop.0+0xac/0x150 [ 81.896306] el0_svc_handler+0x34/0x88 [ 81.897744] el0_svc+0x8/0xc [ 81.898715] ---[ end trace b4a703802243cbba ]--- Fixes: 2b188cc1bb857a9d ("Add io_uring IO interface") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-block@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-05-01io_uring: fix SQPOLL cpu validationMark Rutland1-7/+3
In io_sq_offload_start(), we call cpu_possible() on an unbounded cpu value from userspace. On v5.1-rc7 on arm64 with CONFIG_DEBUG_PER_CPU_MAPS, this results in a splat: WARNING: CPU: 1 PID: 27601 at include/linux/cpumask.h:121 cpu_max_bits_warn include/linux/cpumask.h:121 [inline] There was an attempt to fix this in commit: 917257daa0fea7a0 ("io_uring: only test SQPOLL cpu after we've verified it") ... by adding a check after the cpu value had been limited to NR_CPU_IDS using array_index_nospec(). However, this left an unbound check at the start of the function, for which the warning still fires. Let's fix this correctly by checking that the cpu value is bound by nr_cpu_ids before passing it to cpu_possible(). Note that only nr_cpu_ids of a cpumask are guaranteed to exist at runtime, and nr_cpu_ids can be significantly smaller than NR_CPUs. For example, an arm64 defconfig has NR_CPUS=256, while my test VM has 4 vCPUs. Following the intent from the commit message for 917257daa0fea7a0, the check is moved under the SQ_AFF branch, which is the only branch where the cpu values is consumed. The check is performed before bounding the value with array_index_nospec() so that we don't silently accept bogus cpu values from userspace, where array_index_nospec() would force these values to 0. I suspect we can remove the array_index_nospec() call entirely, but I've conservatively left that in place, updated to use nr_cpu_ids to match the prior check. Tested on arm64 with the Syzkaller reproducer: https://syzkaller.appspot.com/bug?extid=cd714a07c6de2bc34293 https://syzkaller.appspot.com/x/repro.syz?x=15d8b397200000 Full splat from before this patch: WARNING: CPU: 1 PID: 27601 at include/linux/cpumask.h:121 cpu_max_bits_warn include/linux/cpumask.h:121 [inline] WARNING: CPU: 1 PID: 27601 at include/linux/cpumask.h:121 cpumask_check include/linux/cpumask.h:128 [inline] WARNING: CPU: 1 PID: 27601 at include/linux/cpumask.h:121 cpumask_test_cpu include/linux/cpumask.h:344 [inline] WARNING: CPU: 1 PID: 27601 at include/linux/cpumask.h:121 io_sq_offload_start fs/io_uring.c:2244 [inline] WARNING: CPU: 1 PID: 27601 at include/linux/cpumask.h:121 io_uring_create fs/io_uring.c:2864 [inline] WARNING: CPU: 1 PID: 27601 at include/linux/cpumask.h:121 io_uring_setup+0x1108/0x15a0 fs/io_uring.c:2916 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 27601 Comm: syz-executor.0 Not tainted 5.1.0-rc7 #3 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x0/0x2f0 include/linux/compiler.h:193 show_stack+0x20/0x30 arch/arm64/kernel/traps.c:158 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x110/0x190 lib/dump_stack.c:113 panic+0x384/0x68c kernel/panic.c:214 __warn+0x2bc/0x2c0 kernel/panic.c:571 report_bug+0x228/0x2d8 lib/bug.c:186 bug_handler+0xa0/0x1a0 arch/arm64/kernel/traps.c:956 call_break_hook arch/arm64/kernel/debug-monitors.c:301 [inline] brk_handler+0x1d4/0x388 arch/arm64/kernel/debug-monitors.c:316 do_debug_exception+0x1a0/0x468 arch/arm64/mm/fault.c:831 el1_dbg+0x18/0x8c cpu_max_bits_warn include/linux/cpumask.h:121 [inline] cpumask_check include/linux/cpumask.h:128 [inline] cpumask_test_cpu include/linux/cpumask.h:344 [inline] io_sq_offload_start fs/io_uring.c:2244 [inline] io_uring_create fs/io_uring.c:2864 [inline] io_uring_setup+0x1108/0x15a0 fs/io_uring.c:2916 __do_sys_io_uring_setup fs/io_uring.c:2929 [inline] __se_sys_io_uring_setup fs/io_uring.c:2926 [inline] __arm64_sys_io_uring_setup+0x50/0x70 fs/io_uring.c:2926 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall arch/arm64/kernel/syscall.c:47 [inline] el0_svc_common.constprop.0+0x148/0x2e0 arch/arm64/kernel/syscall.c:83 el0_svc_handler+0xdc/0x100 arch/arm64/kernel/syscall.c:129 el0_svc+0x8/0xc arch/arm64/kernel/entry.S:948 SMP: stopping secondary CPUs Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled CPU features: 0x002,23000438 Memory Limit: none Rebooting in 1 seconds.. Fixes: 917257daa0fea7a0 ("io_uring: only test SQPOLL cpu after we've verified it") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-block@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Simplied the logic Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-05-01io_uring: have submission side sqe errors post a cqeJens Axboe1-28/+6
Currently we only post a cqe if we get an error OUTSIDE of submission. For submission, we return the error directly through io_uring_enter(). This is a bit awkward for applications, and it makes more sense to always post a cqe with an error, if the error happens on behalf of an sqe. This changes submission behavior a bit. io_uring_enter() returns -ERROR for an error, and > 0 for number of sqes submitted. Before this change, if you wanted to submit 8 entries and had an error on the 5th entry, io_uring_enter() would return 4 (for number of entries successfully submitted) and rewind the sqring. The application would then have to peek at the sqring and figure out what was wrong with the head sqe, and then skip it itself. With this change, we'll return 5 since we did consume 5 sqes, and the last sqe (with the error) will result in a cqe being posted with the error. This makes the logic easier to handle in the application, and it cleans up the submission part. Suggested-by: Stefan Bühler <source@stbuehler.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-05-01Merge tag 'fsnotify_for_v5.1-rc8' of ↵Linus Torvalds2-8/+18
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify fix from Jan Kara: "A fix of user trigerable NULL pointer dereference syzbot has recently spotted. The problem was introduced in this merge window so no CC stable is needed" * tag 'fsnotify_for_v5.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: fsnotify: Fix NULL ptr deref in fanotify_get_fsid()
2019-04-30io_uring: remove unnecessary barrier after unsetting IORING_SQ_NEED_WAKEUPStefan Bühler1-2/+0
There is no operation to order with afterwards, and removing the flag is not critical in any way. There will always be a "race condition" where the application will trigger IORING_ENTER_SQ_WAKEUP when it isn't actually needed. Signed-off-by: Stefan Bühler <source@stbuehler.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-30io_uring: remove unnecessary barrier after incrementing dropped counterStefan Bühler1-2/+0
smp_store_release in io_commit_sqring already orders the store to dropped before the update to SQ head. Signed-off-by: Stefan Bühler <source@stbuehler.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-30io_uring: remove unnecessary barrier before reading SQ tailStefan Bühler1-2/+0
There is no operation before to order with. Signed-off-by: Stefan Bühler <source@stbuehler.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-30io_uring: remove unnecessary barrier after updating SQ headStefan Bühler1-6/+0
There is no operation afterwards to order with. Signed-off-by: Stefan Bühler <source@stbuehler.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-30io_uring: remove unnecessary barrier before reading cq headStefan Bühler1-2/+5
The memory operations before reading cq head are unrelated and we don't care about their order. Document that the control dependency in combination with READ_ONCE and WRITE_ONCE forms a barrier we need. Signed-off-by: Stefan Bühler <source@stbuehler.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-30io_uring: remove unnecessary barrier before wq_has_sleeperStefan Bühler1-7/+4
wq_has_sleeper has a full barrier internally. The smp_rmb barrier in io_uring_poll synchronizes with it. Signed-off-by: Stefan Bühler <source@stbuehler.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-30io_uring: fix notes on barriersStefan Bühler1-9/+110
The application reading the CQ ring needs a barrier to pair with the smp_store_release in io_commit_cqring, not the barrier after it. Also a write barrier *after* writing something (but not *before* writing anything interesting) doesn't order anything, so an smp_wmb() after writing SQ tail is not needed. Additionally consider reading SQ head and writing CQ tail in the notes. Also add some clarifications how the various other fields in the ring buffers are used. Signed-off-by: Stefan Bühler <source@stbuehler.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-30io_uring: fix handling SQEs requesting NOWAITStefan Bühler1-7/+10
Not all request types set REQ_F_FORCE_NONBLOCK when they needed async punting; reverse logic instead and set REQ_F_NOWAIT if request mustn't be punted. Signed-off-by: Stefan Bühler <source@stbuehler.de> Merged with my previous patch for this. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-29Abort file_remove_privs() for non-reg. filesAlexander Lochmann1-2/+7
file_remove_privs() might be called for non-regular files, e.g. blkdev inode. There is no reason to do its job on things like blkdev inodes, pipes, or cdevs. Hence, abort if file does not refer to a regular inode. AV: more to the point, for devices there might be any number of inodes refering to given device. Which one to strip the permissions from, even if that made any sense in the first place? All of them will be observed with contents modified, after all. Found by LockDoc (Alexander Lochmann, Horst Schirmeier and Olaf Spinczyk) Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Alexander Lochmann <alexander.lochmann@tu-dortmund.de> Signed-off-by: Horst Schirmeier <horst.schirmeier@tu-dortmund.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-29[fix] get rid of checking for absent device name in vfs_get_tree()Al Viro1-5/+0
It has no business being there, it's checked by relevant ->get_tree() as it is *and* it returns the wrong error for no reason whatsoever. Fixes: f3a09c92018a "introduce fs_context methods" Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-28fsnotify: Fix NULL ptr deref in fanotify_get_fsid()Jan Kara2-8/+18
fanotify_get_fsid() is reading mark->connector->fsid under srcu. It can happen that it sees mark not fully initialized or mark that is already detached from the object list. In these cases mark->connector can be NULL leading to NULL ptr dereference. Fix the problem by being careful when reading mark->connector and check it for being NULL. Also use WRITE_ONCE when writing the mark just to prevent compiler from doing something stupid. Reported-by: syzbot+15927486a4f1bfcbaf91@syzkaller.appspotmail.com Fixes: 77115225acc6 ("fanotify: cache fsid in fsnotify_mark_connector") Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-28Merge tag 'for-linus-20190428' of git://git.kernel.dk/linux-blockLinus Torvalds1-16/+26
Pull block fixes from Jens Axboe: "A set of io_uring fixes that should go into this release. In particular, this contains: - The mutex lock vs ctx ref count fix (me) - Removal of a dead variable (me) - Two race fixes (Stefan) - Ring head/tail condition fix for poll full SQ detection (Stefan)" * tag 'for-linus-20190428' of git://git.kernel.dk/linux-block: io_uring: remove 'state' argument from io_{read,write} path io_uring: fix poll full SQ detection io_uring: fix race condition when sq threads goes sleeping io_uring: fix race condition reading SQ entries io_uring: fail io_uring_register(2) on a dying io_uring instance
2019-04-27Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-2/+4
Merge misc fixes from Andrew Morton: "9 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: fs/proc/proc_sysctl.c: Fix a NULL pointer dereference mm/page_alloc.c: fix never set ALLOC_NOFRAGMENT flag mm/page_alloc.c: avoid potential NULL pointer dereference mm, page_alloc: always use a captured page regardless of compaction result mm: do not boost watermarks to avoid fragmentation for the DISCONTIG memory model lib/test_vmalloc.c: do not create cpumask_t variable on stack lib/Kconfig.debug: fix build error without CONFIG_BLOCK zram: pass down the bvec we need to read into in the work struct mm/memory_hotplug.c: drop memory device reference after find_memory_block()