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2021-06-03block: fix a race between del_gendisk and BLKRRPARTGulam Mohamed1-0/+3
[ Upstream commit bc6a385132601c29a6da1dbf8148c0d3c9ad36dc ] When BLKRRPART is called concurrently with del_gendisk, the partitions rescan can create a stale partition that will never be be cleaned up. Fix this by checking the the disk is up before rescanning partitions while under bd_mutex. Signed-off-by: Gulam Mohamed <gulam.mohamed@oracle.com> [hch: split from a larger patch] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210514131842.1600568-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-03SMB3: incorrect file id in requests compounded with openSteve French1-3/+3
[ Upstream commit c0d46717b95735b0eacfddbcca9df37a49de9c7a ] See MS-SMB2 3.2.4.1.4, file ids in compounded requests should be set to 0xFFFFFFFFFFFFFFFF (we were treating it as u32 not u64 and setting it incorrectly). Signed-off-by: Steve French <stfrench@microsoft.com> Reported-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Shyam Prasad N <sprasad@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-03btrfs: do not BUG_ON in link_to_fixup_dirJosef Bacik1-2/+0
[ Upstream commit 91df99a6eb50d5a1bc70fff4a09a0b7ae6aab96d ] While doing error injection testing I got the following panic kernel BUG at fs/btrfs/tree-log.c:1862! invalid opcode: 0000 [#1] SMP NOPTI CPU: 1 PID: 7836 Comm: mount Not tainted 5.13.0-rc1+ #305 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 RIP: 0010:link_to_fixup_dir+0xd5/0xe0 RSP: 0018:ffffb5800180fa30 EFLAGS: 00010216 RAX: fffffffffffffffb RBX: 00000000fffffffb RCX: ffff8f595287faf0 RDX: ffffb5800180fa37 RSI: ffff8f5954978800 RDI: 0000000000000000 RBP: ffff8f5953af9450 R08: 0000000000000019 R09: 0000000000000001 R10: 000151f408682970 R11: 0000000120021001 R12: ffff8f5954978800 R13: ffff8f595287faf0 R14: ffff8f5953c77dd0 R15: 0000000000000065 FS: 00007fc5284c8c40(0000) GS:ffff8f59bbd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc5287f47c0 CR3: 000000011275e002 CR4: 0000000000370ee0 Call Trace: replay_one_buffer+0x409/0x470 ? btree_read_extent_buffer_pages+0xd0/0x110 walk_up_log_tree+0x157/0x1e0 walk_log_tree+0xa6/0x1d0 btrfs_recover_log_trees+0x1da/0x360 ? replay_one_extent+0x7b0/0x7b0 open_ctree+0x1486/0x1720 btrfs_mount_root.cold+0x12/0xea ? __kmalloc_track_caller+0x12f/0x240 legacy_get_tree+0x24/0x40 vfs_get_tree+0x22/0xb0 vfs_kern_mount.part.0+0x71/0xb0 btrfs_mount+0x10d/0x380 ? vfs_parse_fs_string+0x4d/0x90 legacy_get_tree+0x24/0x40 vfs_get_tree+0x22/0xb0 path_mount+0x433/0xa10 __x64_sys_mount+0xe3/0x120 do_syscall_64+0x3d/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae We can get -EIO or any number of legitimate errors from btrfs_search_slot(), panicing here is not the appropriate response. The error path for this code handles errors properly, simply return the error. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-03btrfs: release path before starting transaction when cloning inline extentFilipe Manana1-0/+5
[ Upstream commit 6416954ca75baed71640bf3828625bf165fb9b5e ] When cloning an inline extent there are a few cases, such as when we have an implicit hole at file offset 0, where we start a transaction while holding a read lock on a leaf. Starting the transaction results in a call to sb_start_intwrite(), which results in doing a read lock on a percpu semaphore. Lockdep doesn't like this and complains about it: [46.580704] ====================================================== [46.580752] WARNING: possible circular locking dependency detected [46.580799] 5.13.0-rc1 #28 Not tainted [46.580832] ------------------------------------------------------ [46.580877] cloner/3835 is trying to acquire lock: [46.580918] c00000001301d638 (sb_internal#2){.+.+}-{0:0}, at: clone_copy_inline_extent+0xe4/0x5a0 [46.581167] [46.581167] but task is already holding lock: [46.581217] c000000007fa2550 (btrfs-tree-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x70/0x1d0 [46.581293] [46.581293] which lock already depends on the new lock. [46.581293] [46.581351] [46.581351] the existing dependency chain (in reverse order) is: [46.581410] [46.581410] -> #1 (btrfs-tree-00){++++}-{3:3}: [46.581464] down_read_nested+0x68/0x200 [46.581536] __btrfs_tree_read_lock+0x70/0x1d0 [46.581577] btrfs_read_lock_root_node+0x88/0x200 [46.581623] btrfs_search_slot+0x298/0xb70 [46.581665] btrfs_set_inode_index+0xfc/0x260 [46.581708] btrfs_new_inode+0x26c/0x950 [46.581749] btrfs_create+0xf4/0x2b0 [46.581782] lookup_open.isra.57+0x55c/0x6a0 [46.581855] path_openat+0x418/0xd20 [46.581888] do_filp_open+0x9c/0x130 [46.581920] do_sys_openat2+0x2ec/0x430 [46.581961] do_sys_open+0x90/0xc0 [46.581993] system_call_exception+0x3d4/0x410 [46.582037] system_call_common+0xec/0x278 [46.582078] [46.582078] -> #0 (sb_internal#2){.+.+}-{0:0}: [46.582135] __lock_acquire+0x1e90/0x2c50 [46.582176] lock_acquire+0x2b4/0x5b0 [46.582263] start_transaction+0x3cc/0x950 [46.582308] clone_copy_inline_extent+0xe4/0x5a0 [46.582353] btrfs_clone+0x5fc/0x880 [46.582388] btrfs_clone_files+0xd8/0x1c0 [46.582434] btrfs_remap_file_range+0x3d8/0x590 [46.582481] do_clone_file_range+0x10c/0x270 [46.582558] vfs_clone_file_range+0x1b0/0x310 [46.582605] ioctl_file_clone+0x90/0x130 [46.582651] do_vfs_ioctl+0x874/0x1ac0 [46.582697] sys_ioctl+0x6c/0x120 [46.582733] system_call_exception+0x3d4/0x410 [46.582777] system_call_common+0xec/0x278 [46.582822] [46.582822] other info that might help us debug this: [46.582822] [46.582888] Possible unsafe locking scenario: [46.582888] [46.582942] CPU0 CPU1 [46.582984] ---- ---- [46.583028] lock(btrfs-tree-00); [46.583062] lock(sb_internal#2); [46.583119] lock(btrfs-tree-00); [46.583174] lock(sb_internal#2); [46.583212] [46.583212] *** DEADLOCK *** [46.583212] [46.583266] 6 locks held by cloner/3835: [46.583299] #0: c00000001301d448 (sb_writers#12){.+.+}-{0:0}, at: ioctl_file_clone+0x90/0x130 [46.583382] #1: c00000000f6d3768 (&sb->s_type->i_mutex_key#15){+.+.}-{3:3}, at: lock_two_nondirectories+0x58/0xc0 [46.583477] #2: c00000000f6d72a8 (&sb->s_type->i_mutex_key#15/4){+.+.}-{3:3}, at: lock_two_nondirectories+0x9c/0xc0 [46.583574] #3: c00000000f6d7138 (&ei->i_mmap_lock){+.+.}-{3:3}, at: btrfs_remap_file_range+0xd0/0x590 [46.583657] #4: c00000000f6d35f8 (&ei->i_mmap_lock/1){+.+.}-{3:3}, at: btrfs_remap_file_range+0xe0/0x590 [46.583743] #5: c000000007fa2550 (btrfs-tree-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x70/0x1d0 [46.583828] [46.583828] stack backtrace: [46.583872] CPU: 1 PID: 3835 Comm: cloner Not tainted 5.13.0-rc1 #28 [46.583931] Call Trace: [46.583955] [c0000000167c7200] [c000000000c1ee78] dump_stack+0xec/0x144 (unreliable) [46.584052] [c0000000167c7240] [c000000000274058] print_circular_bug.isra.32+0x3a8/0x400 [46.584123] [c0000000167c72e0] [c0000000002741f4] check_noncircular+0x144/0x190 [46.584191] [c0000000167c73b0] [c000000000278fc0] __lock_acquire+0x1e90/0x2c50 [46.584259] [c0000000167c74f0] [c00000000027aa94] lock_acquire+0x2b4/0x5b0 [46.584317] [c0000000167c75e0] [c000000000a0d6cc] start_transaction+0x3cc/0x950 [46.584388] [c0000000167c7690] [c000000000af47a4] clone_copy_inline_extent+0xe4/0x5a0 [46.584457] [c0000000167c77c0] [c000000000af525c] btrfs_clone+0x5fc/0x880 [46.584514] [c0000000167c7990] [c000000000af5698] btrfs_clone_files+0xd8/0x1c0 [46.584583] [c0000000167c7a00] [c000000000af5b58] btrfs_remap_file_range+0x3d8/0x590 [46.584652] [c0000000167c7ae0] [c0000000005d81dc] do_clone_file_range+0x10c/0x270 [46.584722] [c0000000167c7b40] [c0000000005d84f0] vfs_clone_file_range+0x1b0/0x310 [46.584793] [c0000000167c7bb0] [c00000000058bf80] ioctl_file_clone+0x90/0x130 [46.584861] [c0000000167c7c10] [c00000000058c894] do_vfs_ioctl+0x874/0x1ac0 [46.584922] [c0000000167c7d10] [c00000000058db4c] sys_ioctl+0x6c/0x120 [46.584978] [c0000000167c7d60] [c0000000000364a4] system_call_exception+0x3d4/0x410 [46.585046] [c0000000167c7e10] [c00000000000d45c] system_call_common+0xec/0x278 [46.585114] --- interrupt: c00 at 0x7ffff7e22990 [46.585160] NIP: 00007ffff7e22990 LR: 00000001000010ec CTR: 0000000000000000 [46.585224] REGS: c0000000167c7e80 TRAP: 0c00 Not tainted (5.13.0-rc1) [46.585280] MSR: 800000000280f033 <SF,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE> CR: 28000244 XER: 00000000 [46.585374] IRQMASK: 0 [46.585374] GPR00: 0000000000000036 00007fffffffdec0 00007ffff7f17100 0000000000000004 [46.585374] GPR04: 000000008020940d 00007fffffffdf40 0000000000000000 0000000000000000 [46.585374] GPR08: 0000000000000004 0000000000000000 0000000000000000 0000000000000000 [46.585374] GPR12: 0000000000000000 00007ffff7ffa940 0000000000000000 0000000000000000 [46.585374] GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [46.585374] GPR20: 0000000000000000 000000009123683e 00007fffffffdf40 0000000000000000 [46.585374] GPR24: 0000000000000000 0000000000000000 0000000000000000 0000000000000004 [46.585374] GPR28: 0000000100030260 0000000100030280 0000000000000003 000000000000005f [46.585919] NIP [00007ffff7e22990] 0x7ffff7e22990 [46.585964] LR [00000001000010ec] 0x1000010ec [46.586010] --- interrupt: c00 This should be a false positive, as both locks are acquired in read mode. Nevertheless, we don't need to hold a leaf locked when we start the transaction, so just release the leaf (path) before starting it. Reported-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/linux-btrfs/20210513214404.xks77p566fglzgum@riteshh-domain/ Reviewed-by: Anand Jain <anand.jain@oracle.com> 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: Sasha Levin <sashal@kernel.org>
2021-06-03btrfs: return whole extents in fiemapBoris Burkov1-1/+6
[ Upstream commit 15c7745c9a0078edad1f7df5a6bb7b80bc8cca23 ] `xfs_io -c 'fiemap <off> <len>' <file>` can give surprising results on btrfs that differ from xfs. btrfs prints out extents trimmed to fit the user input. If the user's fiemap request has an offset, then rather than returning each whole extent which intersects that range, we also trim the start extent to not have start < off. Documentation in filesystems/fiemap.txt and the xfs_io man page suggests that returning the whole extent is expected. Some cases which all yield the same fiemap in xfs, but not btrfs: dd if=/dev/zero of=$f bs=4k count=1 sudo xfs_io -c 'fiemap 0 1024' $f 0: [0..7]: 26624..26631 sudo xfs_io -c 'fiemap 2048 1024' $f 0: [4..7]: 26628..26631 sudo xfs_io -c 'fiemap 2048 4096' $f 0: [4..7]: 26628..26631 sudo xfs_io -c 'fiemap 3584 512' $f 0: [7..7]: 26631..26631 sudo xfs_io -c 'fiemap 4091 5' $f 0: [7..6]: 26631..26630 I believe this is a consequence of the logic for merging contiguous extents represented by separate extent items. That logic needs to track the last offset as it loops through the extent items, which happens to pick up the start offset on the first iteration, and trim off the beginning of the full extent. To fix it, start `off` at 0 rather than `start` so that we keep the iteration/merging intact without cutting off the start of the extent. after the fix, all the above commands give: 0: [0..7]: 26624..26631 The merging logic is exercised by fstest generic/483, and I have written a new fstest for checking we don't have backwards or zero-length fiemaps for cases like those above. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-03afs: Fix the nlink handling of dir-over-dir renameDavid Howells1-1/+3
commit f610a5a29c3cfb7d37bdfa4ef52f72ea51f24a76 upstream. Fix rename of one directory over another such that the nlink on the deleted directory is cleared to 0 rather than being decremented to 1. This was causing the generic/035 xfstest to fail. Fixes: e49c7b2f6de7 ("afs: Build an abstraction around an "operation" concept") Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/162194384460.3999479.7605572278074191079.stgit@warthog.procyon.org.uk/ # v1 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03NFSv4: Fix v4.0/v4.1 SEEK_DATA return -ENOTSUPP when set NFS_V4_2 configZhang Xiaoxu1-1/+1
commit e67afa7ee4a59584d7253e45d7f63b9528819a13 upstream. Since commit bdcc2cd14e4e ("NFSv4.2: handle NFS-specific llseek errors"), nfs42_proc_llseek would return -EOPNOTSUPP rather than -ENOTSUPP when SEEK_DATA on NFSv4.0/v4.1. This will lead xfstests generic/285 not run on NFSv4.0/v4.1 when set the CONFIG_NFS_V4_2, rather than run failed. Fixes: bdcc2cd14e4e ("NFSv4.2: handle NFS-specific llseek errors") Cc: <stable.vger.kernel.org> # 4.2 Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03NFS: Don't corrupt the value of pg_bytes_written in nfs_do_recoalesce()Trond Myklebust1-7/+5
commit 0d0ea309357dea0d85a82815f02157eb7fcda39f upstream. The value of mirror->pg_bytes_written should only be updated after a successful attempt to flush out the requests on the list. Fixes: a7d42ddb3099 ("nfs: add mirroring support to pgio layer") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03NFS: Fix an Oopsable condition in __nfs_pageio_add_request()Trond Myklebust1-4/+5
commit 56517ab958b7c11030e626250c00b9b1a24b41eb upstream. Ensure that nfs_pageio_error_cleanup() resets the mirror array contents, so that the structure reflects the fact that it is now empty. Also change the test in nfs_pageio_do_add_request() to be more robust by checking whether or not the list is empty rather than relying on the value of pg_count. Fixes: a7d42ddb3099 ("nfs: add mirroring support to pgio layer") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03NFS: fix an incorrect limit in filelayout_decode_layout()Dan Carpenter1-1/+1
commit 769b01ea68b6c49dc3cde6adf7e53927dacbd3a8 upstream. The "sizeof(struct nfs_fh)" is two bytes too large and could lead to memory corruption. It should be NFS_MAXFHSIZE because that's the size of the ->data[] buffer. I reversed the size of the arguments to put the variable on the left. Fixes: 16b374ca439f ("NFSv4.1: pnfs: filelayout: add driver's LAYOUTGET and GETDEVICEINFO infrastructure") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03fs/nfs: Use fatal_signal_pending instead of signal_pendingzhouchuangao1-2/+2
commit bb002388901151fe35b6697ab116f6ed0721a9ed upstream. We set the state of the current process to TASK_KILLABLE via prepare_to_wait(). Should we use fatal_signal_pending() to detect the signal here? Fixes: b4868b44c562 ("NFSv4: Wait for stateid updates after CLOSE/OPEN_DOWNGRADE") Signed-off-by: zhouchuangao <zhouchuangao@vivo.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03proc: Check /proc/$pid/attr/ writes against file openerKees Cook1-0/+4
commit bfb819ea20ce8bbeeba17e1a6418bf8bda91fc28 upstream. Fix another "confused deputy" weakness[1]. Writes to /proc/$pid/attr/ files need to check the opener credentials, since these fds do not transition state across execve(). Without this, it is possible to trick another process (which may have different credentials) to write to its own /proc/$pid/attr/ files, leading to unexpected and possibly exploitable behaviors. [1] https://www.kernel.org/doc/html/latest/security/credentials.html?highlight=confused#open-file-credentials Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03NFSv4: Fix a NULL pointer dereference in pnfs_mark_matching_lsegs_return()Anna Schumaker1-8/+7
commit a421d218603ffa822a0b8045055c03eae394a7eb upstream. Commit de144ff4234f changes _pnfs_return_layout() to call pnfs_mark_matching_lsegs_return() passing NULL as the struct pnfs_layout_range argument. Unfortunately, pnfs_mark_matching_lsegs_return() doesn't check if we have a value here before dereferencing it, causing an oops. I'm able to hit this crash consistently when running connectathon basic tests on NFS v4.1/v4.2 against Ontap. Fixes: de144ff4234f ("NFSv4: Don't discard segments marked for return in _pnfs_return_layout()") Cc: stable@vger.kernel.org Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03cifs: set server->cipher_type to AES-128-CCM for SMB3.0Aurelien Aptel1-0/+7
commit 6d2fcfe6b517fe7cbf2687adfb0a16cdcd5d9243 upstream. SMB3.0 doesn't have encryption negotiate context but simply uses the SMB2_GLOBAL_CAP_ENCRYPTION flag. When that flag is present in the neg response cifs.ko uses AES-128-CCM which is the only cipher available in this context. cipher_type was set to the server cipher only when parsing encryption negotiate context (SMB3.1.1). For SMB3.0 it was set to 0. This means cipher_type value can be 0 or 1 for AES-128-CCM. Fix this by checking for SMB3.0 and encryption capability and setting cipher_type appropriately. Signed-off-by: Aurelien Aptel <aaptel@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-26Revert "ecryptfs: replace BUG_ON with error handling code"Greg Kroah-Hartman1-4/+2
commit e1436df2f2550bc89d832ffd456373fdf5d5b5d7 upstream. This reverts commit 2c2a7552dd6465e8fde6bc9cccf8d66ed1c1eb72. Because of recent interactions with developers from @umn.edu, all commits from them have been recently re-reviewed to ensure if they were correct or not. Upon review, this commit was found to be incorrect for the reasons below, so it must be reverted. It will be fixed up "correctly" in a later kernel change. The original commit log for this change was incorrect, no "error handling code" was added, things will blow up just as badly as before if any of these cases ever were true. As this BUG_ON() never fired, and most of these checks are "obviously" never going to be true, let's just revert to the original code for now until this gets unwound to be done correctly in the future. Cc: Aditya Pakki <pakki001@umn.edu> Fixes: 2c2a7552dd64 ("ecryptfs: replace BUG_ON with error handling code") Cc: stable <stable@vger.kernel.org> Acked-by: Tyler Hicks <code@tyhicks.com> Link: https://lore.kernel.org/r/20210503115736.2104747-49-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-26cifs: fix memory leak in smb2_copychunk_rangeRonnie Sahlberg1-0/+2
commit d201d7631ca170b038e7f8921120d05eec70d7c5 upstream. When using smb2_copychunk_range() for large ranges we will run through several iterations of a loop calling SMB2_ioctl() but never actually free the returned buffer except for the final iteration. This leads to memory leaks everytime a large copychunk is requested. Fixes: 9bf0c9cd4314 ("CIFS: Fix SMB2/SMB3 Copy offload support (refcopy) for large files") Cc: <stable@vger.kernel.org> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-26btrfs: avoid RCU stalls while running delayed iputsJosef Bacik1-0/+1
commit 71795ee590111e3636cc3c148289dfa9fa0a5fc3 upstream. Generally a delayed iput is added when we might do the final iput, so usually we'll end up sleeping while processing the delayed iputs naturally. However there's no guarantee of this, especially for small files. In production we noticed 5 instances of RCU stalls while testing a kernel release overnight across 1000 machines, so this is relatively common: host count: 5 rcu: INFO: rcu_sched self-detected stall on CPU rcu: ....: (20998 ticks this GP) idle=59e/1/0x4000000000000002 softirq=12333372/12333372 fqs=3208 (t=21031 jiffies g=27810193 q=41075) NMI backtrace for cpu 1 CPU: 1 PID: 1713 Comm: btrfs-cleaner Kdump: loaded Not tainted 5.6.13-0_fbk12_rc1_5520_gec92bffc1ec9 #1 Call Trace: <IRQ> dump_stack+0x50/0x70 nmi_cpu_backtrace.cold.6+0x30/0x65 ? lapic_can_unplug_cpu.cold.30+0x40/0x40 nmi_trigger_cpumask_backtrace+0xba/0xca rcu_dump_cpu_stacks+0x99/0xc7 rcu_sched_clock_irq.cold.90+0x1b2/0x3a3 ? trigger_load_balance+0x5c/0x200 ? tick_sched_do_timer+0x60/0x60 ? tick_sched_do_timer+0x60/0x60 update_process_times+0x24/0x50 tick_sched_timer+0x37/0x70 __hrtimer_run_queues+0xfe/0x270 hrtimer_interrupt+0xf4/0x210 smp_apic_timer_interrupt+0x5e/0x120 apic_timer_interrupt+0xf/0x20 </IRQ> RIP: 0010:queued_spin_lock_slowpath+0x17d/0x1b0 RSP: 0018:ffffc9000da5fe48 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffff889fa81d0cd8 RCX: 0000000000000029 RDX: ffff889fff86c0c0 RSI: 0000000000080000 RDI: ffff88bfc2da7200 RBP: ffff888f2dcdd768 R08: 0000000001040000 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff82a55560 R12: ffff88bfc2da7200 R13: 0000000000000000 R14: ffff88bff6c2a360 R15: ffffffff814bd870 ? kzalloc.constprop.57+0x30/0x30 list_lru_add+0x5a/0x100 inode_lru_list_add+0x20/0x40 iput+0x1c1/0x1f0 run_delayed_iput_locked+0x46/0x90 btrfs_run_delayed_iputs+0x3f/0x60 cleaner_kthread+0xf2/0x120 kthread+0x10b/0x130 Fix this by adding a cond_resched_lock() to the loop processing delayed iputs so we can avoid these sort of stalls. CC: stable@vger.kernel.org # 4.9+ Reviewed-by: Rik van Riel <riel@surriel.com> Signed-off-by: Josef Bacik <josef@toxicpanda.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>
2021-05-22block: reexpand iov_iter after read/writeyangerkun1-3/+17
[ Upstream commit cf7b39a0cbf6bf57aa07a008d46cf695add05b4c ] We get a bug: BUG: KASAN: slab-out-of-bounds in iov_iter_revert+0x11c/0x404 lib/iov_iter.c:1139 Read of size 8 at addr ffff0000d3fb11f8 by task CPU: 0 PID: 12582 Comm: syz-executor.2 Not tainted 5.10.0-00843-g352c8610ccd2 #2 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x0/0x2d0 arch/arm64/kernel/stacktrace.c:132 show_stack+0x28/0x34 arch/arm64/kernel/stacktrace.c:196 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x110/0x164 lib/dump_stack.c:118 print_address_description+0x78/0x5c8 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [inline] kasan_report+0x148/0x1e4 mm/kasan/report.c:562 check_memory_region_inline mm/kasan/generic.c:183 [inline] __asan_load8+0xb4/0xbc mm/kasan/generic.c:252 iov_iter_revert+0x11c/0x404 lib/iov_iter.c:1139 io_read fs/io_uring.c:3421 [inline] io_issue_sqe+0x2344/0x2d64 fs/io_uring.c:5943 __io_queue_sqe+0x19c/0x520 fs/io_uring.c:6260 io_queue_sqe+0x2a4/0x590 fs/io_uring.c:6326 io_submit_sqe fs/io_uring.c:6395 [inline] io_submit_sqes+0x4c0/0xa04 fs/io_uring.c:6624 __do_sys_io_uring_enter fs/io_uring.c:9013 [inline] __se_sys_io_uring_enter fs/io_uring.c:8960 [inline] __arm64_sys_io_uring_enter+0x190/0x708 fs/io_uring.c:8960 __invoke_syscall arch/arm64/kernel/syscall.c:36 [inline] invoke_syscall arch/arm64/kernel/syscall.c:48 [inline] el0_svc_common arch/arm64/kernel/syscall.c:158 [inline] do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:227 el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367 el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383 el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670 Allocated by task 12570: stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121 kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc+0xdc/0x120 mm/kasan/common.c:461 kasan_kmalloc+0xc/0x14 mm/kasan/common.c:475 __kmalloc+0x23c/0x334 mm/slub.c:3970 kmalloc include/linux/slab.h:557 [inline] __io_alloc_async_data+0x68/0x9c fs/io_uring.c:3210 io_setup_async_rw fs/io_uring.c:3229 [inline] io_read fs/io_uring.c:3436 [inline] io_issue_sqe+0x2954/0x2d64 fs/io_uring.c:5943 __io_queue_sqe+0x19c/0x520 fs/io_uring.c:6260 io_queue_sqe+0x2a4/0x590 fs/io_uring.c:6326 io_submit_sqe fs/io_uring.c:6395 [inline] io_submit_sqes+0x4c0/0xa04 fs/io_uring.c:6624 __do_sys_io_uring_enter fs/io_uring.c:9013 [inline] __se_sys_io_uring_enter fs/io_uring.c:8960 [inline] __arm64_sys_io_uring_enter+0x190/0x708 fs/io_uring.c:8960 __invoke_syscall arch/arm64/kernel/syscall.c:36 [inline] invoke_syscall arch/arm64/kernel/syscall.c:48 [inline] el0_svc_common arch/arm64/kernel/syscall.c:158 [inline] do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:227 el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367 el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383 el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670 Freed by task 12570: stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121 kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track+0x38/0x6c mm/kasan/common.c:56 kasan_set_free_info+0x20/0x40 mm/kasan/generic.c:355 __kasan_slab_free+0x124/0x150 mm/kasan/common.c:422 kasan_slab_free+0x10/0x1c mm/kasan/common.c:431 slab_free_hook mm/slub.c:1544 [inline] slab_free_freelist_hook mm/slub.c:1577 [inline] slab_free mm/slub.c:3142 [inline] kfree+0x104/0x38c mm/slub.c:4124 io_dismantle_req fs/io_uring.c:1855 [inline] __io_free_req+0x70/0x254 fs/io_uring.c:1867 io_put_req_find_next fs/io_uring.c:2173 [inline] __io_queue_sqe+0x1fc/0x520 fs/io_uring.c:6279 __io_req_task_submit+0x154/0x21c fs/io_uring.c:2051 io_req_task_submit+0x2c/0x44 fs/io_uring.c:2063 task_work_run+0xdc/0x128 kernel/task_work.c:151 get_signal+0x6f8/0x980 kernel/signal.c:2562 do_signal+0x108/0x3a4 arch/arm64/kernel/signal.c:658 do_notify_resume+0xbc/0x25c arch/arm64/kernel/signal.c:722 work_pending+0xc/0x180 blkdev_read_iter can truncate iov_iter's count since the count + pos may exceed the size of the blkdev. This will confuse io_read that we have consume the iovec. And once we do the iov_iter_revert in io_read, we will trigger the slab-out-of-bounds. Fix it by reexpand the count with size has been truncated. blkdev_write_iter can trigger the problem too. Signed-off-by: yangerkun <yangerkun@huawei.com> Acked-by: Pavel Begunkov <asml.silencec@gmail.com> Link: https://lore.kernel.org/r/20210401071807.3328235-1-yangerkun@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-22ceph: don't allow access to MDS-private inodesJeff Layton4-0/+42
[ Upstream commit d4f6b31d721779d91b5e2f8072478af73b196c34 ] The MDS reserves a set of inodes for its own usage, and these should never be accessible to clients. Add a new helper to vet a proposed inode number against that range, and complain loudly and refuse to create or look it up if it's in it. Also, ensure that the MDS doesn't try to delegate inodes that are in that range or lower. Print a warning if it does, and don't save the range in the xarray. URL: https://tracker.ceph.com/issues/49922 Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Xiubo Li <xiubli@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-22ceph: don't clobber i_snap_caps on non-I_NEW inodeJeff Layton1-4/+5
[ Upstream commit d3c51ae1b8cce5bdaf91a1ce32b33cf5626075dc ] We want the snapdir to mirror the non-snapped directory's attributes for most things, but i_snap_caps represents the caps granted on the snapshot directory by the MDS itself. A misbehaving MDS could issue different caps for the snapdir and we lose them here. Only reset i_snap_caps when the inode is I_NEW. Also, move the setting of i_op and i_fop inside the if block since they should never change anyway. Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-22ceph: fix fscache invalidationJeff Layton2-0/+2
[ Upstream commit 10a7052c7868bc7bc72d947f5aac6f768928db87 ] Ensure that we invalidate the fscache whenever we invalidate the pagecache. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-22NFS: NFS_INO_REVAL_PAGECACHE should mark the change attribute invalidTrond Myklebust1-1/+2
[ Upstream commit 50c7a7994dd20af56e4d47e90af10bab71b71001 ] When we're looking to revalidate the page cache, we should just ensure that we mark the change attribute invalid. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19ext4: fix debug format string warningArnd Bergmann2-4/+3
commit fcdf3c34b7abdcbb49690c94c7fa6ce224dc9749 upstream. Using no_printk() for jbd_debug() revealed two warnings: fs/jbd2/recovery.c: In function 'fc_do_one_pass': fs/jbd2/recovery.c:256:30: error: format '%d' expects a matching 'int' argument [-Werror=format=] 256 | jbd_debug(3, "Processing fast commit blk with seq %d"); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/ext4/fast_commit.c: In function 'ext4_fc_replay_add_range': fs/ext4/fast_commit.c:1732:30: error: format '%d' expects argument of type 'int', but argument 2 has type 'long unsigned int' [-Werror=format=] 1732 | jbd_debug(1, "Converting from %d to %d %lld", The first one was added incorrectly, and was also missing a few newlines in debug output, and the second one happened when the type of an argument changed. Reported-by: kernel test robot <lkp@intel.com> Fixes: d556435156b7 ("jbd2: avoid -Wempty-body warnings") Fixes: 6db074618969 ("ext4: use BIT() macro for BH_** state bits") Fixes: 5b849b5f96b4 ("jbd2: fast commit recovery path") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20210409201211.1866633-1-arnd@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-19debugfs: Make debugfs_allow RO after initKees Cook1-1/+1
commit 312723a0b34d6d110aa4427a982536bb36ab8471 upstream. Since debugfs_allow is only set at boot time during __init, make it read-only after being set. Fixes: a24c6f7bc923 ("debugfs: Add access restriction option") Cc: Peter Enderborg <peter.enderborg@sony.com> Reviewed-by: Peter Enderborg <peter.enderborg@sony.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210405213959.3079432-1-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-19f2fs: compress: fix to assign cc.cluster_idx correctlyChao Yu3-12/+13
[ Upstream commit 8bfbfb0ddd706b1ce2e89259ecc45f192c0ec2bf ] In f2fs_destroy_compress_ctx(), after f2fs_destroy_compress_ctx(), cc.cluster_idx will be cleared w/ NULL_CLUSTER, f2fs_cluster_blocks() may check wrong cluster metadata, fix it. Fixes: 4c8ff7095bef ("f2fs: support data compression") Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19f2fs: compress: fix race condition of overwrite vs truncateChao Yu1-23/+12
[ Upstream commit a949dc5f2c5cfe0c910b664650f45371254c0744 ] pos_fsstress testcase complains a panic as belew: ------------[ cut here ]------------ kernel BUG at fs/f2fs/compress.c:1082! invalid opcode: 0000 [#1] SMP PTI CPU: 4 PID: 2753477 Comm: kworker/u16:2 Tainted: G OE 5.12.0-rc1-custom #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 Workqueue: writeback wb_workfn (flush-252:16) RIP: 0010:prepare_compress_overwrite+0x4c0/0x760 [f2fs] Call Trace: f2fs_prepare_compress_overwrite+0x5f/0x80 [f2fs] f2fs_write_cache_pages+0x468/0x8a0 [f2fs] f2fs_write_data_pages+0x2a4/0x2f0 [f2fs] do_writepages+0x38/0xc0 __writeback_single_inode+0x44/0x2a0 writeback_sb_inodes+0x223/0x4d0 __writeback_inodes_wb+0x56/0xf0 wb_writeback+0x1dd/0x290 wb_workfn+0x309/0x500 process_one_work+0x220/0x3c0 worker_thread+0x53/0x420 kthread+0x12f/0x150 ret_from_fork+0x22/0x30 The root cause is truncate() may race with overwrite as below, so that one reference count left in page can not guarantee the page attaching in mapping tree all the time, after truncation, later find_lock_page() may return NULL pointer. - prepare_compress_overwrite - f2fs_pagecache_get_page - unlock_page - f2fs_setattr - truncate_setsize - truncate_inode_page - delete_from_page_cache - find_lock_page Fix this by avoiding referencing updated page. Fixes: 4c8ff7095bef ("f2fs: support data compression") Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19f2fs: compress: fix to free compress page correctlyChao Yu1-1/+2
[ Upstream commit a12cc5b423d4f36dc1a1ea3911e49cf9dff43898 ] In error path of f2fs_write_compressed_pages(), it needs to call f2fs_compress_free_page() to release temporary page. Fixes: 5e6bbde95982 ("f2fs: introduce mempool for {,de}compress intermediate page allocation") Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19dax: Wake up all waiters after invalidating dax entryVivek Goyal1-1/+1
[ Upstream commit 237388320deffde7c2d65ed8fc9eef670dc979b3 ] I am seeing missed wakeups which ultimately lead to a deadlock when I am using virtiofs with DAX enabled and running "make -j". I had to mount virtiofs as rootfs and also reduce to dax window size to 256M to reproduce the problem consistently. So here is the problem. put_unlocked_entry() wakes up waiters only if entry is not null as well as !dax_is_conflict(entry). But if I call multiple instances of invalidate_inode_pages2() in parallel, then I can run into a situation where there are waiters on this index but nobody will wake these waiters. invalidate_inode_pages2() invalidate_inode_pages2_range() invalidate_exceptional_entry2() dax_invalidate_mapping_entry_sync() __dax_invalidate_entry() { xas_lock_irq(&xas); entry = get_unlocked_entry(&xas, 0); ... ... dax_disassociate_entry(entry, mapping, trunc); xas_store(&xas, NULL); ... ... put_unlocked_entry(&xas, entry); xas_unlock_irq(&xas); } Say a fault in in progress and it has locked entry at offset say "0x1c". Now say three instances of invalidate_inode_pages2() are in progress (A, B, C) and they all try to invalidate entry at offset "0x1c". Given dax entry is locked, all tree instances A, B, C will wait in wait queue. When dax fault finishes, say A is woken up. It will store NULL entry at index "0x1c" and wake up B. When B comes along it will find "entry=0" at page offset 0x1c and it will call put_unlocked_entry(&xas, 0). And this means put_unlocked_entry() will not wake up next waiter, given the current code. And that means C continues to wait and is not woken up. This patch fixes the issue by waking up all waiters when a dax entry has been invalidated. This seems to fix the deadlock I am facing and I can make forward progress. Reported-by: Sergio Lopez <slp@redhat.com> Fixes: ac401cc78242 ("dax: New fault locking") Reviewed-by: Jan Kara <jack@suse.cz> Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Link: https://lore.kernel.org/r/20210428190314.1865312-4-vgoyal@redhat.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19dax: Add a wakeup mode parameter to put_unlocked_entry()Vivek Goyal1-7/+7
[ Upstream commit 4c3d043d271d4d629aa2328796cdfc96b37d3b3c ] As of now put_unlocked_entry() always wakes up next waiter. In next patches we want to wake up all waiters at one callsite. Hence, add a parameter to the function. This patch does not introduce any change of behavior. Reviewed-by: Greg Kurz <groug@kaod.org> Reviewed-by: Jan Kara <jack@suse.cz> Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Link: https://lore.kernel.org/r/20210428190314.1865312-3-vgoyal@redhat.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19dax: Add an enum for specifying dax wakup modeVivek Goyal1-6/+17
[ Upstream commit 698ab77aebffe08b312fbcdddeb0e8bd08b78717 ] Dan mentioned that he is not very fond of passing around a boolean true/false to specify if only next waiter should be woken up or all waiters should be woken up. He instead prefers that we introduce an enum and make it very explicity at the callsite itself. Easier to read code. This patch should not introduce any change of behavior. Reviewed-by: Greg Kurz <groug@kaod.org> Reviewed-by: Jan Kara <jack@suse.cz> Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Link: https://lore.kernel.org/r/20210428190314.1865312-2-vgoyal@redhat.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19btrfs: fix race leading to unpersisted data and metadata on fsyncFilipe Manana2-12/+27
commit 626e9f41f7c281ba3e02843702f68471706aa6d9 upstream. When doing a fast fsync on a file, there is a race which can result in the fsync returning success to user space without logging the inode and without durably persisting new data. The following example shows one possible scenario for this: $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ touch /mnt/bar $ xfs_io -f -c "pwrite -S 0xab 0 1M" -c "fsync" /mnt/baz # Now we have: # file bar == inode 257 # file baz == inode 258 $ mv /mnt/baz /mnt/foo # Now we have: # file bar == inode 257 # file foo == inode 258 $ xfs_io -c "pwrite -S 0xcd 0 1M" /mnt/foo # fsync bar before foo, it is important to trigger the race. $ xfs_io -c "fsync" /mnt/bar $ xfs_io -c "fsync" /mnt/foo # After this: # inode 257, file bar, is empty # inode 258, file foo, has 1M filled with 0xcd <power failure> # Replay the log: $ mount /dev/sdc /mnt # After this point file foo should have 1M filled with 0xcd and not 0xab The following steps explain how the race happens: 1) Before the first fsync of inode 258, when it has the "baz" name, its ->logged_trans is 0, ->last_sub_trans is 0 and ->last_log_commit is -1. The inode also has the full sync flag set; 2) After the first fsync, we set inode 258 ->logged_trans to 6, which is the generation of the current transaction, and set ->last_log_commit to 0, which is the current value of ->last_sub_trans (done at btrfs_log_inode()). The full sync flag is cleared from the inode during the fsync. The log sub transaction that was committed had an ID of 0 and when we synced the log, at btrfs_sync_log(), we incremented root->log_transid from 0 to 1; 3) During the rename: We update inode 258, through btrfs_update_inode(), and that causes its ->last_sub_trans to be set to 1 (the current log transaction ID), and ->last_log_commit remains with a value of 0. After updating inode 258, because we have previously logged the inode in the previous fsync, we log again the inode through the call to btrfs_log_new_name(). This results in updating the inode's ->last_log_commit from 0 to 1 (the current value of its ->last_sub_trans). The ->last_sub_trans of inode 257 is updated to 1, which is the ID of the next log transaction; 4) Then a buffered write against inode 258 is made. This leaves the value of ->last_sub_trans as 1 (the ID of the current log transaction, stored at root->log_transid); 5) Then an fsync against inode 257 (or any other inode other than 258), happens. This results in committing the log transaction with ID 1, which results in updating root->last_log_commit to 1 and bumping root->log_transid from 1 to 2; 6) Then an fsync against inode 258 starts. We flush delalloc and wait only for writeback to complete, since the full sync flag is not set in the inode's runtime flags - we do not wait for ordered extents to complete. Then, at btrfs_sync_file(), we call btrfs_inode_in_log() before the ordered extent completes. The call returns true: static inline bool btrfs_inode_in_log(...) { bool ret = false; spin_lock(&inode->lock); if (inode->logged_trans == generation && inode->last_sub_trans <= inode->last_log_commit && inode->last_sub_trans <= inode->root->last_log_commit) ret = true; spin_unlock(&inode->lock); return ret; } generation has a value of 6 (fs_info->generation), ->logged_trans also has a value of 6 (set when we logged the inode during the first fsync and when logging it during the rename), ->last_sub_trans has a value of 1, set during the rename (step 3), ->last_log_commit also has a value of 1 (set in step 3) and root->last_log_commit has a value of 1, which was set in step 5 when fsyncing inode 257. As a consequence we don't log the inode, any new extents and do not sync the log, resulting in a data loss if a power failure happens after the fsync and before the current transaction commits. Also, because we do not log the inode, after a power failure the mtime and ctime of the inode do not match those we had before. When the ordered extent completes before we call btrfs_inode_in_log(), then the call returns false and we log the inode and sync the log, since at the end of ordered extent completion we update the inode and set ->last_sub_trans to 2 (the value of root->log_transid) and ->last_log_commit to 1. This problem is found after removing the check for the emptiness of the inode's list of modified extents in the recent commit 209ecbb8585bf6 ("btrfs: remove stale comment and logic from btrfs_inode_in_log()"), added in the 5.13 merge window. However checking the emptiness of the list is not really the way to solve this problem, and was never intended to, because while that solves the problem for COW writes, the problem persists for NOCOW writes because in that case the list is always empty. In the case of NOCOW writes, even though we wait for the writeback to complete before returning from btrfs_sync_file(), we end up not logging the inode, which has a new mtime/ctime, and because we don't sync the log, we never issue disk barriers (send REQ_PREFLUSH to the device) since that only happens when we sync the log (when we write super blocks at btrfs_sync_log()). So effectively, for a NOCOW case, when we return from btrfs_sync_file() to user space, we are not guaranteeing that the data is durably persisted on disk. Also, while the example above uses a rename exchange to show how the problem happens, it is not the only way to trigger it. An alternative could be adding a new hard link to inode 258, since that also results in calling btrfs_log_new_name() and updating the inode in the log. An example reproducer using the addition of a hard link instead of a rename operation: $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ touch /mnt/bar $ xfs_io -f -c "pwrite -S 0xab 0 1M" -c "fsync" /mnt/foo $ ln /mnt/foo /mnt/foo_link $ xfs_io -c "pwrite -S 0xcd 0 1M" /mnt/foo $ xfs_io -c "fsync" /mnt/bar $ xfs_io -c "fsync" /mnt/foo <power failure> # Replay the log: $ mount /dev/sdc /mnt # After this point file foo often has 1M filled with 0xab and not 0xcd The reasons leading to the final fsync of file foo, inode 258, not persisting the new data are the same as for the previous example with a rename operation. So fix by never skipping logging and log syncing when there are still any ordered extents in flight. To avoid making the conditional if statement that checks if logging an inode is needed harder to read, place all the logic into an helper function with separate if statements to make it more manageable and easier to read. A test case for fstests will follow soon. For NOCOW writes, the problem existed before commit b5e6c3e170b770 ("btrfs: always wait on ordered extents at fsync time"), introduced in kernel 4.19, then it went away with that commit since we started to always wait for ordered extent completion before logging. The problem came back again once the fast fsync path was changed again to avoid waiting for ordered extent completion, in commit 487781796d3022 ("btrfs: make fast fsyncs wait only for writeback"), added in kernel 5.10. However, for COW writes, the race only happens after the recent commit 209ecbb8585bf6 ("btrfs: remove stale comment and logic from btrfs_inode_in_log()"), introduced in the 5.13 merge window. For NOCOW writes, the bug existed before that commit. So tag 5.10+ as the release for stable backports. CC: stable@vger.kernel.org # 5.10+ 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>
2021-05-19mm/hugetlb: fix F_SEAL_FUTURE_WRITEPeter Xu1-0/+5
commit 22247efd822e6d263f3c8bd327f3f769aea9b1d9 upstream. Patch series "mm/hugetlb: Fix issues on file sealing and fork", v2. Hugh reported issue with F_SEAL_FUTURE_WRITE not applied correctly to hugetlbfs, which I can easily verify using the memfd_test program, which seems that the program is hardly run with hugetlbfs pages (as by default shmem). Meanwhile I found another probably even more severe issue on that hugetlb fork won't wr-protect child cow pages, so child can potentially write to parent private pages. Patch 2 addresses that. After this series applied, "memfd_test hugetlbfs" should start to pass. This patch (of 2): F_SEAL_FUTURE_WRITE is missing for hugetlb starting from the first day. There is a test program for that and it fails constantly. $ ./memfd_test hugetlbfs memfd-hugetlb: CREATE memfd-hugetlb: BASIC memfd-hugetlb: SEAL-WRITE memfd-hugetlb: SEAL-FUTURE-WRITE mmap() didn't fail as expected Aborted (core dumped) I think it's probably because no one is really running the hugetlbfs test. Fix it by checking FUTURE_WRITE also in hugetlbfs_file_mmap() as what we do in shmem_mmap(). Generalize a helper for that. Link: https://lkml.kernel.org/r/20210503234356.9097-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20210503234356.9097-2-peterx@redhat.com Fixes: ab3948f58ff84 ("mm/memfd: add an F_SEAL_FUTURE_WRITE seal to memfd") Signed-off-by: Peter Xu <peterx@redhat.com> Reported-by: Hugh Dickins <hughd@google.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torv