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KCSAN: data-race in ext4_writepages / generic_write_end (3)

Status: closed as invalid on 2022/05/13 11:20
Subsystems: ext4
[Documentation on labels]
First crash: 690d, last: 686d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in ext4_writepages / generic_write_end (2) ext4 1 784d 784d 0/26 auto-closed as invalid on 2022/03/10 19:17
upstream KCSAN: data-race in ext4_writepages / generic_write_end ext4 691 828d 1351d 0/26 auto-closed as invalid on 2022/01/25 08:29

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ext4_writepages / generic_write_end

write to 0xffff8881210b97c8 of 8 bytes by task 4661 on cpu 1:
 i_size_write include/linux/fs.h:878 [inline]
 generic_write_end+0x98/0x230 fs/buffer.c:2183
 ext4_da_write_end+0x26c/0x620 fs/ext4/inode.c:3068
 generic_perform_write+0x26a/0x3f0 mm/filemap.c:3798
 ext4_buffered_write_iter+0x222/0x330 fs/ext4/file.c:270
 ext4_file_write_iter+0x2e3/0x1210
 call_write_iter include/linux/fs.h:2050 [inline]
 new_sync_write fs/read_write.c:504 [inline]
 vfs_write+0x71c/0x890 fs/read_write.c:591
 ksys_write+0xe8/0x1a0 fs/read_write.c:644
 __do_sys_write fs/read_write.c:656 [inline]
 __se_sys_write fs/read_write.c:653 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:653
 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+0x44/0xae

read to 0xffff8881210b97c8 of 8 bytes by task 4668 on cpu 0:
 i_size_read include/linux/fs.h:856 [inline]
 mpage_submit_page fs/ext4/inode.c:2084 [inline]
 mpage_map_and_submit_buffers fs/ext4/inode.c:2336 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2475 [inline]
 ext4_writepages+0xfd9/0x1d00 fs/ext4/inode.c:2804
 do_writepages+0x1db/0x350 mm/page-writeback.c:2352
 filemap_fdatawrite_wbc+0xd6/0xf0 mm/filemap.c:388
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 __filemap_fdatawrite mm/filemap.c:427 [inline]
 filemap_flush+0x93/0xc0 mm/filemap.c:454
 ext4_alloc_da_blocks+0x47/0x100 fs/ext4/inode.c:3112
 ext4_release_file+0x5b/0x1d0 fs/ext4/file.c:143
 __fput+0x292/0x510 fs/file_table.c:317
 ____fput+0x11/0x20 fs/file_table.c:350
 task_work_run+0x8e/0x110 kernel/task_work.c:164
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x124/0x130 kernel/entry/common.c:169
 exit_to_user_mode_prepare kernel/entry/common.c:201 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x6a/0x90 kernel/entry/common.c:294
 do_syscall_64+0x37/0x70 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000005f7000 -> 0x00000000005f9000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4668 Comm: syz-executor.3 Not tainted 5.18.0-rc6-syzkaller-00009-gfeb9c5e19e91 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/12/2022
==================================================================

Crashes (26):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/05/12 13:18 upstream feb9c5e19e91 9ad6612a .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/11 16:51 upstream feb9c5e19e91 beb0b407 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/10 23:21 upstream feb9c5e19e91 8d7b3b67 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 16:24 upstream 9be9ed2612b5 8b277b8e .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 16:21 upstream 9be9ed2612b5 8b277b8e .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 08:29 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 06:43 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 06:22 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 05:59 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 05:46 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 05:40 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 05:21 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 04:15 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 03:29 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 03:18 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 03:08 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 02:47 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/09 01:36 upstream c5eb0a61238d e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/08 22:52 upstream 379c72654524 e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/08 22:28 upstream 379c72654524 e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/08 19:59 upstream 379c72654524 e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/08 19:22 upstream 379c72654524 e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/08 19:15 upstream 379c72654524 e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/08 18:54 upstream 379c72654524 e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/08 18:10 upstream 379c72654524 e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
2022/05/08 17:49 upstream 379c72654524 e60b1103 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_writepages / generic_write_end
* Struck through repros no longer work on HEAD.