syzbot


KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached (2)

Status: moderation: reported on 2024/11/12 11:03
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+10f039cf2ae179d227c5@syzkaller.appspotmail.com
First crash: 159d, last: 10d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached ext4 7 203d 250d 0/28 auto-obsoleted due to no activity on 2024/11/03 13:08

Sample crash report:
==================================================================
BUG: KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached

write to 0xffff888117d660c8 of 4 bytes by task 3754 on cpu 1:
 inode_cgwb_move_to_attached+0x9a/0x300 fs/fs-writeback.c:309
 writeback_single_inode+0x2b5/0x3f0 fs/fs-writeback.c:1818
 sync_inode_metadata+0x60/0x90 fs/fs-writeback.c:2883
 generic_buffers_fsync_noflush+0xd8/0x120 fs/buffer.c:610
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1c3/0x6c0 fs/ext4/fsync.c:147
 vfs_fsync_range+0x116/0x130 fs/sync.c:187
 generic_write_sync include/linux/fs.h:2976 [inline]
 ext4_buffered_write_iter+0x358/0x3c0 fs/ext4/file.c:305
 ext4_file_write_iter+0x3b2/0xf80 include/linux/fs.h:-1
 iter_file_splice_write+0x5f2/0x980 fs/splice.c:738
 do_splice_from fs/splice.c:935 [inline]
 direct_splice_actor+0x160/0x2c0 fs/splice.c:1158
 splice_direct_to_actor+0x305/0x680 fs/splice.c:1102
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0xd9/0x150 fs/splice.c:1227
 do_sendfile+0x40a/0x690 fs/read_write.c:1368
 __do_sys_sendfile64 fs/read_write.c:1429 [inline]
 __se_sys_sendfile64 fs/read_write.c:1415 [inline]
 __x64_sys_sendfile64+0x113/0x160 fs/read_write.c:1415
 x64_sys_call+0xfc3/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888117d660c8 of 4 bytes by task 3749 on cpu 0:
 generic_buffers_fsync_noflush+0x83/0x120 fs/buffer.c:605
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1c3/0x6c0 fs/ext4/fsync.c:147
 vfs_fsync_range+0x116/0x130 fs/sync.c:187
 generic_write_sync include/linux/fs.h:2976 [inline]
 ext4_buffered_write_iter+0x358/0x3c0 fs/ext4/file.c:305
 ext4_file_write_iter+0x3b2/0xf80 include/linux/fs.h:-1
 iter_file_splice_write+0x5f2/0x980 fs/splice.c:738
 do_splice_from fs/splice.c:935 [inline]
 direct_splice_actor+0x160/0x2c0 fs/splice.c:1158
 splice_direct_to_actor+0x305/0x680 fs/splice.c:1102
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0xd9/0x150 fs/splice.c:1227
 do_sendfile+0x40a/0x690 fs/read_write.c:1368
 __do_sys_sendfile64 fs/read_write.c:1429 [inline]
 __se_sys_sendfile64 fs/read_write.c:1415 [inline]
 __x64_sys_sendfile64+0x113/0x160 fs/read_write.c:1415
 x64_sys_call+0xfc3/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000002 -> 0x00000020

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3749 Comm: syz.0.102 Not tainted 6.15.0-rc1-syzkaller-00095-g2eb959eeecc6 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================

Crashes (21):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/10 20:12 upstream 2eb959eeecc6 1ef3ab4d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/04/10 20:12 upstream 2eb959eeecc6 1ef3ab4d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/04/08 09:00 upstream 0af2f6be1b42 a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/03/30 03:44 upstream 7d06015d936c d3999433 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/03/24 17:52 upstream 38fec10eb60d 875573af .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/03/22 16:16 upstream 88d324e69ea9 c6512ef7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/02/08 03:13 upstream 7ee983c850b4 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/01/20 08:30 upstream ffd294d346d1 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/01/16 09:41 upstream 619f0b6fad52 968edaf4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/01/13 01:36 upstream be548645527a 6dbc6a9b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/01/10 11:26 upstream 643e2e259c2b 67d7ec0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/01/09 23:53 upstream 643e2e259c2b 9220929f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/01/09 10:56 upstream eea6e4b4dfb8 9220929f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2025/01/04 00:41 upstream 63676eefb7a0 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2024/12/22 22:59 upstream bcde95ce32b6 b4fbdbd4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2024/12/18 14:37 upstream aef25be35d23 a0626d3a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2024/12/12 15:17 upstream 231825b2e1ff 530e80f8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2024/12/11 03:43 upstream f92f4749861b cfc402b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2024/12/07 16:35 upstream b5f217084ab3 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2024/11/17 21:14 upstream 4a5df3796467 cfe3a04a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
2024/11/12 11:03 upstream 2d5404caa8c7 75bb1b32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in generic_buffers_fsync_noflush / inode_cgwb_move_to_attached
* Struck through repros no longer work on HEAD.