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KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers

Status: auto-closed as invalid on 2020/04/08 22:27
Subsystems: exfat
[Documentation on labels]
First crash: 2401d, last: 2331d
▶ ▼ Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (8) exfat 6 1 845d 845d 0/29 auto-obsoleted due to no activity on 2024/03/30 16:35
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (4) ext4 6 5 2007d 2019d 0/29 auto-closed as invalid on 2021/01/23 11:44
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (12) exfat 6 1 107d 107d 0/29 auto-obsoleted due to no activity on 2026/04/28 18:33
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (11) exfat 6 12 192d 389d 0/29 auto-obsoleted due to no activity on 2026/02/01 21:20
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (3) exfat 6 10 2093d 2184d 0/29 auto-closed as invalid on 2020/10/29 18:32
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (7) exfat 6 42 894d 922d 0/29 auto-obsoleted due to no activity on 2024/02/03 09:04
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (2) exfat 6 1 2222d 2222d 0/29 closed as invalid on 2020/06/18 14:13
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (9) exfat 6 44 608d 737d 0/29 auto-obsoleted due to no activity on 2024/11/21 22:27
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (6) exfat 6 174 1016d 1657d 0/29 auto-obsoleted due to no activity on 2023/10/11 19:19
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (5) exfat 6 32 1697d 1924d 0/29 auto-closed as invalid on 2021/11/29 11:14
upstream KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers (10) exfat 6 57 453d 537d 0/29 auto-obsoleted due to no activity on 2025/05/10 19:27

Sample crash report:
==================================================================
BUG: KCSAN: data-race in mark_buffer_dirty_inode / sync_mapping_buffers

read to 0xffff88812534ea18 of 8 bytes by task 15980 on cpu 1:
 mark_buffer_dirty_inode+0xa1/0x260 fs/buffer.c:596
 fat16_ent_put+0x82/0x90 fs/fat/fatent.c:182
 fat_alloc_clusters+0x507/0xc40 fs/fat/fatent.c:501
 fat_add_cluster+0x3d/0xd0 fs/fat/inode.c:107
 fat_fallocate+0x152/0x1f0 fs/fat/file.c:291
 vfs_fallocate+0x3be/0x650 fs/open.c:309
 ioctl_preallocate+0x12b/0x190 fs/ioctl.c:491
 file_ioctl fs/ioctl.c:537 [inline]
 do_vfs_ioctl+0xb14/0xcf0 fs/ioctl.c:732
 ksys_ioctl+0xbd/0xe0 fs/ioctl.c:749
 __do_sys_ioctl fs/ioctl.c:756 [inline]
 __se_sys_ioctl fs/ioctl.c:754 [inline]
 __x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:754
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff88812534ea18 of 8 bytes by task 15989 on cpu 0:
 fsync_buffers_list fs/buffer.c:774 [inline]
 sync_mapping_buffers+0x4eb/0x6e0 fs/buffer.c:563
 fat_file_fsync+0xd4/0x120 fs/fat/file.c:194
 vfs_fsync_range+0x82/0x150 fs/sync.c:197
 generic_write_sync include/linux/fs.h:2856 [inline]
 generic_file_write_iter+0x318/0x38c mm/filemap.c:3474
 call_write_iter include/linux/fs.h:1902 [inline]
 do_iter_readv_writev+0x487/0x5b0 fs/read_write.c:693
 do_iter_write fs/read_write.c:970 [inline]
 do_iter_write+0x13b/0x3c0 fs/read_write.c:951
 vfs_iter_write+0x5c/0x80 fs/read_write.c:983
 iter_file_splice_write+0x530/0x840 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:1464
 __do_sys_sendfile64 fs/read_write.c:1525 [inline]
 __se_sys_sendfile64 fs/read_write.c:1511 [inline]
 __x64_sys_sendfile64+0x12a/0x140 fs/read_write.c:1511
 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: 15989 Comm: syz-executor.1 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/01/29 22:24 https://github.com/google/ktsan.git kcsan 245a43005292 5ed23f9a .config console log report ci2-upstream-kcsan-gce
2020/01/28 05:27 https://github.com/google/ktsan.git kcsan 245a43005292 56cd6c9b .config console log report ci2-upstream-kcsan-gce
2020/01/27 08:57 https://github.com/google/ktsan.git kcsan 245a43005292 dd56146d .config console log report ci2-upstream-kcsan-gce
2020/01/26 13:24 https://github.com/google/ktsan.git kcsan 245a43005292 f4e7270e .config console log report ci2-upstream-kcsan-gce
2020/01/22 22:07 https://github.com/google/ktsan.git kcsan 245a43005292 3334d684 .config console log report ci2-upstream-kcsan-gce
2020/01/17 01:09 https://github.com/google/ktsan.git kcsan 245a43005292 3de7aabb .config console log report ci2-upstream-kcsan-gce
2019/12/02 06:45 https://github.com/google/ktsan.git kcsan ef798c30ba4e f879db37 .config console log report ci2-upstream-kcsan-gce
2019/11/21 16:51 https://github.com/google/ktsan.git kcsan 5863cc791e4c 8098ea0f .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.