syzbot


KCSAN: data-race in xas_find_marked / xas_set_mark

Status: moderation: reported on 2019/12/05 04:45
Subsystems: fs mm
[Documentation on labels]
Reported-by: syzbot+238e9bb046564c2c4d4a@syzkaller.appspotmail.com
First crash: 2016d, last: 8h22m

Sample crash report:
==================================================================
BUG: KCSAN: data-race in xas_find_marked / xas_set_mark

write to 0xffff8881065d8b84 of 4 bytes by task 17582 on cpu 1:
 xa_mark_set lib/xarray.c:71 [inline]
 xas_set_mark+0x12b/0x140 lib/xarray.c:900
 __folio_start_writeback+0x1dd/0x430 mm/page-writeback.c:3096
 ext4_bio_write_folio+0x590/0x9d0 fs/ext4/page-io.c:583
 mpage_submit_folio fs/ext4/inode.c:1937 [inline]
 mpage_process_page_bufs+0x46c/0x5b0 fs/ext4/inode.c:2050
 mpage_prepare_extent_to_map+0x775/0xb80 fs/ext4/inode.c:2551
 ext4_do_writepages+0xa25/0x2270 fs/ext4/inode.c:2737
 ext4_writepages+0x176/0x300 fs/ext4/inode.c:2829
 do_writepages+0x1d2/0x480 mm/page-writeback.c:2656
 filemap_fdatawrite_wbc mm/filemap.c:386 [inline]
 __filemap_fdatawrite_range mm/filemap.c:419 [inline]
 file_write_and_wait_range+0x156/0x2c0 mm/filemap.c:794
 generic_buffers_fsync_noflush+0x45/0x120 fs/buffer.c:611
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1ab/0x690 fs/ext4/fsync.c:147
 vfs_fsync_range+0x10a/0x130 fs/sync.c:187
 generic_write_sync include/linux/fs.h:2976 [inline]
 ext4_buffered_write_iter+0x34f/0x3c0 fs/ext4/file.c:305
 ext4_file_write_iter+0x383/0xf00 fs/ext4/file.c:-1
 iter_file_splice_write+0x5ef/0x970 fs/splice.c:738
 do_splice_from fs/splice.c:935 [inline]
 direct_splice_actor+0x153/0x2a0 fs/splice.c:1158
 splice_direct_to_actor+0x30f/0x680 fs/splice.c:1102
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0xda/0x150 fs/splice.c:1227
 do_sendfile+0x380/0x640 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+0x105/0x150 fs/read_write.c:1415
 x64_sys_call+0xb39/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881065d8b84 of 4 bytes by task 17598 on cpu 0:
 xa_marked include/linux/xarray.h:424 [inline]
 xas_find_marked+0x5dc/0x620 lib/xarray.c:1483
 find_get_entry+0x5d/0x380 mm/filemap.c:2027
 filemap_get_folios_tag+0x92/0x210 mm/filemap.c:2295
 mpage_prepare_extent_to_map+0x330/0xb80 fs/ext4/inode.c:2453
 ext4_do_writepages+0x6eb/0x2270 fs/ext4/inode.c:2692
 ext4_writepages+0x176/0x300 fs/ext4/inode.c:2829
 do_writepages+0x1d2/0x480 mm/page-writeback.c:2656
 filemap_fdatawrite_wbc mm/filemap.c:386 [inline]
 __filemap_fdatawrite_range mm/filemap.c:419 [inline]
 file_write_and_wait_range+0x156/0x2c0 mm/filemap.c:794
 generic_buffers_fsync_noflush+0x45/0x120 fs/buffer.c:611
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1ab/0x690 fs/ext4/fsync.c:147
 vfs_fsync_range+0x10a/0x130 fs/sync.c:187
 generic_write_sync include/linux/fs.h:2976 [inline]
 ext4_buffered_write_iter+0x34f/0x3c0 fs/ext4/file.c:305
 ext4_file_write_iter+0x383/0xf00 fs/ext4/file.c:-1
 iter_file_splice_write+0x5ef/0x970 fs/splice.c:738
 do_splice_from fs/splice.c:935 [inline]
 direct_splice_actor+0x153/0x2a0 fs/splice.c:1158
 splice_direct_to_actor+0x30f/0x680 fs/splice.c:1102
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0xda/0x150 fs/splice.c:1227
 do_sendfile+0x380/0x640 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+0x105/0x150 fs/read_write.c:1415
 x64_sys_call+0xb39/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0a000021 -> 0x04000021

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 17598 Comm: syz.6.5329 Not tainted 6.15.0-rc4-syzkaller-00021-gca91b9500108 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
==================================================================

Crashes (1909):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/29 20:21 upstream ca91b9500108 85a5a23f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/29 09:09 upstream ca91b9500108 aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/27 23:53 upstream b4432656b36e c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/27 03:14 upstream 5bc1018675ec c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/26 08:40 upstream f1a3944c860b c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/25 19:32 upstream 02ddfb981de8 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/25 05:52 upstream 02ddfb981de8 e3715315 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/24 19:19 upstream e72e9e693307 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/24 19:19 upstream e72e9e693307 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/24 07:27 upstream a79be02bba5c 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/23 19:30 upstream a79be02bba5c 73a168d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/23 18:08 upstream bc3372351d0c 73a168d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/22 22:06 upstream bc3372351d0c 53a8b9bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/22 20:33 upstream a33b5a08cbbd 53a8b9bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/22 04:09 upstream a33b5a08cbbd 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/21 08:37 upstream 9d7a0577c9db 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/20 18:48 upstream 6fea5fabd332 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/20 05:32 upstream 119009db2674 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/19 16:21 upstream 8560697b23dc 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/19 02:41 upstream 3088d26962e8 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/18 12:51 upstream fc96b232f8e7 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/18 00:07 upstream b5c6891b2c5b 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/17 09:26 upstream cfb2e2c57aef 229db4cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/17 06:55 upstream cfb2e2c57aef a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/16 17:26 upstream c62f4b82d571 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/16 00:13 upstream 1a1d569a75f3 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/15 12:27 upstream 834a4a689699 23b969b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/14 09:00 upstream 8ffd015db85f 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/13 16:11 upstream 5aaaedb0cb54 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/13 01:38 upstream 7cdabafc0012 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/12 17:04 upstream 3bde70a2c827 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/11 20:50 upstream e618ee89561b 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/11 06:46 upstream 900241a5cc15 94486846 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/10 16:54 upstream 2eb959eeecc6 1ef3ab4d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/10 00:55 upstream 3b07108ada81 988b336c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/09 11:15 upstream a24588245776 47d015b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/09 02:20 upstream bec7dcbc242c a775275d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/07 20:14 upstream 0af2f6be1b42 a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/06 23:21 upstream 0af2f6be1b42 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/06 12:35 upstream f4d2ef48250a 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/06 02:20 upstream a8662bcd2ff1 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/05 19:11 upstream a8662bcd2ff1 c53ea9c9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/05 13:14 upstream a52a3c18cdf3 c53ea9c9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/04 23:51 upstream a52a3c18cdf3 1c4febdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/04 11:31 upstream e48e99b6edf4 1c4febdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/03 20:07 upstream a2cc6ff5ec8f d7ae3a11 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/03 16:18 upstream a1b5bd45d4ee 996a9618 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/02 20:52 upstream 92b71befc349 c799dfdd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2025/04/02 07:15 upstream acc4d5ff0b61 c799dfdd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_find_marked / xas_set_mark
2021/01/16 09:14 upstream 1d94330a437a 65a7a854 .config console log report info ci2-upstream-kcsan-gce
2019/10/23 02:27 https://github.com/google/ktsan.git kcsan 05f2236801fe d0686497 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.