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KCSAN: data-race in __writeback_single_inode / ext4_sync_file

Status: auto-closed as invalid on 2020/05/03 19:14
Subsystems: ext4
[Documentation on labels]
First crash: 1592d, last: 1523d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __writeback_single_inode / ext4_sync_file (4) ext4 6 975d 1014d 0/26 auto-closed as invalid on 2021/09/28 17:33
upstream KCSAN: data-race in __writeback_single_inode / ext4_sync_file (3) ext4 72 1056d 1235d 0/26 auto-closed as invalid on 2021/07/09 15:43
upstream KCSAN: data-race in __writeback_single_inode / ext4_sync_file (5) ext4 1 895d 895d 0/26 auto-closed as invalid on 2021/12/16 21:26
upstream KCSAN: data-race in __writeback_single_inode / ext4_sync_file (2) ext4 3 1419d 1439d 0/26 closed as invalid on 2020/06/18 14:13

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __writeback_single_inode / ext4_sync_file

write to 0xffff8880af22f340 of 8 bytes by task 15498 on cpu 1:
 __writeback_single_inode+0x328/0x8e0 fs/fs-writeback.c:1486
 writeback_single_inode+0x232/0x310 fs/fs-writeback.c:1565
 sync_inode fs/fs-writeback.c:2602 [inline]
 sync_inode_metadata+0x74/0xa0 fs/fs-writeback.c:2622
 ext4_fsync_nojournal fs/ext4/fsync.c:94 [inline]
 ext4_sync_file+0x470/0x8c0 fs/ext4/fsync.c:172
 vfs_fsync_range+0x82/0x150 fs/sync.c:197
 generic_write_sync include/linux/fs.h:2867 [inline]
 ext4_buffered_write_iter+0x222/0x290 fs/ext4/file.c:277
 ext4_file_write_iter+0xfa/0xd70 fs/ext4/file.c:642
 call_write_iter include/linux/fs.h:1901 [inline]
 do_iter_readv_writev+0x487/0x5b0 fs/read_write.c:693
 do_iter_write fs/read_write.c:998 [inline]
 do_iter_write+0x13b/0x3c0 fs/read_write.c:979
 vfs_iter_write+0x5c/0x80 fs/read_write.c:1039
 iter_file_splice_write+0x536/0x850 fs/splice.c:760
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0xa0/0xc0 fs/splice.c:1037
 splice_direct_to_actor+0x22b/0x540 fs/splice.c:992
 do_splice_direct+0x161/0x1e0 fs/splice.c:1080
 do_sendfile+0x384/0x7f0 fs/read_write.c:1520
 __do_sys_sendfile64 fs/read_write.c:1581 [inline]
 __se_sys_sendfile64 fs/read_write.c:1567 [inline]
 __x64_sys_sendfile64+0x12a/0x140 fs/read_write.c:1567
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880af22f340 of 8 bytes by task 15506 on cpu 0:
 ext4_fsync_nojournal fs/ext4/fsync.c:89 [inline]
 ext4_sync_file+0x405/0x8c0 fs/ext4/fsync.c:172
 vfs_fsync_range+0x82/0x150 fs/sync.c:197
 generic_write_sync include/linux/fs.h:2867 [inline]
 ext4_buffered_write_iter+0x222/0x290 fs/ext4/file.c:277
 ext4_file_write_iter+0xfa/0xd70 fs/ext4/file.c:642
 call_write_iter include/linux/fs.h:1901 [inline]
 do_iter_readv_writev+0x487/0x5b0 fs/read_write.c:693
 do_iter_write fs/read_write.c:998 [inline]
 do_iter_write+0x13b/0x3c0 fs/read_write.c:979
 vfs_iter_write+0x5c/0x80 fs/read_write.c:1039
 iter_file_splice_write+0x536/0x850 fs/splice.c:760
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0xa0/0xc0 fs/splice.c:1037
 splice_direct_to_actor+0x22b/0x540 fs/splice.c:992
 do_splice_direct+0x161/0x1e0 fs/splice.c:1080
 do_sendfile+0x384/0x7f0 fs/read_write.c:1520
 __do_sys_sendfile64 fs/read_write.c:1581 [inline]
 __se_sys_sendfile64 fs/read_write.c:1567 [inline]
 __x64_sys_sendfile64+0x12a/0x140 fs/read_write.c:1567
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15506 Comm: syz-executor.0 Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (15):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/02/23 19:04 https://github.com/google/ktsan.git kcsan 766d004d1b85 2c36e7a7 .config console log report ci2-upstream-kcsan-gce
2020/02/18 19:40 https://github.com/google/ktsan.git kcsan b12d66a6c34f 012fbc32 .config console log report ci2-upstream-kcsan-gce
2020/02/08 09:34 https://github.com/google/ktsan.git kcsan 6cccb8ba35bd 06150bf1 .config console log report ci2-upstream-kcsan-gce
2020/02/02 13:47 https://github.com/google/ktsan.git kcsan 245a43005292 93e5e335 .config console log report ci2-upstream-kcsan-gce
2020/01/24 23:32 https://github.com/google/ktsan.git kcsan 245a43005292 2e95ab33 .config console log report ci2-upstream-kcsan-gce
2020/01/22 23:42 https://github.com/google/ktsan.git kcsan 245a43005292 3334d684 .config console log report ci2-upstream-kcsan-gce
2020/01/20 13:01 https://github.com/google/ktsan.git kcsan 245a43005292 c40da18c .config console log report ci2-upstream-kcsan-gce
2020/01/16 20:08 https://github.com/google/ktsan.git kcsan 245a43005292 3de7aabb .config console log report ci2-upstream-kcsan-gce
2020/01/14 20:25 https://github.com/google/ktsan.git kcsan 245a43005292 fa12bd3c .config console log report ci2-upstream-kcsan-gce
2020/01/13 01:02 https://github.com/google/ktsan.git kcsan 245a43005292 53faa9fe .config console log report ci2-upstream-kcsan-gce
2020/01/10 19:29 https://github.com/google/ktsan.git kcsan 245a43005292 532ec44e .config console log report ci2-upstream-kcsan-gce
2020/01/07 00:25 https://github.com/google/ktsan.git kcsan 245a43005292 53430d97 .config console log report ci2-upstream-kcsan-gce
2020/01/07 00:17 https://github.com/google/ktsan.git kcsan 245a43005292 53430d97 .config console log report ci2-upstream-kcsan-gce
2019/12/31 01:49 https://github.com/google/ktsan.git kcsan 245a43005292 6b36d338 .config console log report ci2-upstream-kcsan-gce
2019/12/16 11:54 https://github.com/google/ktsan.git kcsan 245a43005292 0ae38e44 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.