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KCSAN: data-race in __writeback_single_inode / vfs_fsync_range (8)

Status: auto-obsoleted due to no activity on 2023/04/01 19:00
Subsystems: ext4 exfat
[Documentation on labels]
First crash: 620d, last: 613d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __writeback_single_inode / vfs_fsync_range ext4 2 1775d 1777d 0/28 closed as invalid on 2019/11/19 14:44
upstream KCSAN: data-race in __writeback_single_inode / vfs_fsync_range (7) exfat 1 925d 925d 0/28 auto-closed as invalid on 2022/04/13 08:14
upstream KCSAN: data-race in __writeback_single_inode / vfs_fsync_range (6) ext4 1 1241d 1241d 0/28 auto-closed as invalid on 2021/06/01 07:24
upstream KCSAN: data-race in __writeback_single_inode / vfs_fsync_range (5) exfat 2 1318d 1335d 0/28 auto-closed as invalid on 2021/03/15 14:17
upstream KCSAN: data-race in __writeback_single_inode / vfs_fsync_range (9) ext4 2 5d17h 9d18h 0/28 moderation: reported on 2024/09/09 18:07
upstream KCSAN: data-race in __writeback_single_inode / vfs_fsync_range (3) ext4 2 1513d 1540d 0/28 auto-closed as invalid on 2020/09/02 05:07
upstream KCSAN: data-race in __writeback_single_inode / vfs_fsync_range (2) ext4 2 1751d 1752d 0/28 auto-closed as invalid on 2020/02/12 06:26
upstream KCSAN: data-race in __writeback_single_inode / vfs_fsync_range (4) ext4 1 1473d 1473d 0/28 auto-closed as invalid on 2020/10/12 03:20

Sample crash report:
loop1: detected capacity change from 0 to 4096
EXT4-fs (loop1): mounted filesystem 00000000-0000-0000-0000-000000000000 without journal. Quota mode: none.
==================================================================
BUG: KCSAN: data-race in __writeback_single_inode / vfs_fsync_range

write to 0xffff8881261cf750 of 8 bytes by task 16048 on cpu 1:
 __writeback_single_inode+0x1f6/0x590 fs/fs-writeback.c:1634
 writeback_single_inode+0x126/0x490 fs/fs-writeback.c:1719
 sync_inode_metadata+0x52/0x70 fs/fs-writeback.c:2775
 ext4_fsync_nojournal fs/ext4/fsync.c:92 [inline]
 ext4_sync_file+0x349/0x6d0 fs/ext4/fsync.c:170
 vfs_fsync_range+0x107/0x120 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2885 [inline]
 ext4_buffered_write_iter+0x398/0x3e0 fs/ext4/file.c:292
 ext4_file_write_iter+0x2bb/0x11b0
 do_iter_write+0x494/0x750 fs/read_write.c:861
 vfs_iter_write+0x4c/0x70 fs/read_write.c:902
 iter_file_splice_write+0x44a/0x7c0 fs/splice.c:686
 do_splice_from fs/splice.c:764 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:931
 splice_direct_to_actor+0x305/0x620 fs/splice.c:886
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff8881261cf750 of 8 bytes by task 16041 on cpu 0:
 vfs_fsync_range+0x98/0x120 fs/sync.c:186
 generic_write_sync include/linux/fs.h:2885 [inline]
 ext4_buffered_write_iter+0x398/0x3e0 fs/ext4/file.c:292
 ext4_file_write_iter+0x2bb/0x11b0
 do_iter_write+0x494/0x750 fs/read_write.c:861
 vfs_iter_write+0x4c/0x70 fs/read_write.c:902
 iter_file_splice_write+0x44a/0x7c0 fs/splice.c:686
 do_splice_from fs/splice.c:764 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:931
 splice_direct_to_actor+0x305/0x620 fs/splice.c:886
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000087 -> 0x0000000000000084

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 16041 Comm: syz-executor.1 Tainted: G        W          6.2.0-rc3-syzkaller-00349-g97ec4d559d93-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/01/14 14:49 upstream 97ec4d559d93 a63719e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __writeback_single_inode / vfs_fsync_range
2023/01/07 18:06 upstream 0a71553536d2 1dac8c7a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __writeback_single_inode / vfs_fsync_range
* Struck through repros no longer work on HEAD.