syzbot


KCSAN: data-race in __mpage_writepage / generic_write_end

Status: closed as invalid on 2020/06/18 14:13
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 994d, last: 963d
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (2) 9 881d 947d 0/24 auto-closed as invalid on 2020/10/09 21:50
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (5) 1 271d 271d 0/24 auto-closed as invalid on 2022/06/11 23:17
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (3) 1 792d 788d 0/24 auto-closed as invalid on 2021/01/07 12:23
upstream KCSAN: data-race in __mpage_writepage / generic_write_end (4) 2 328d 362d 0/24 auto-closed as invalid on 2022/04/16 04:47

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

write to 0xffff88811cd766e8 of 8 bytes by task 13655 on cpu 0:
 i_size_write include/linux/fs.h:894 [inline]
 generic_write_end+0xd4/0x290 fs/buffer.c:2177
 fat_write_end+0x57/0x120 fs/fat/inode.c:250
 generic_perform_write+0x1d7/0x320 mm/filemap.c:3313
 __generic_file_write_iter+0x240/0x370 mm/filemap.c:3431
 generic_file_write_iter+0x294/0x38e mm/filemap.c:3463
 call_write_iter include/linux/fs.h:1907 [inline]
 new_sync_write+0x303/0x400 fs/read_write.c:484
 __vfs_write+0x9e/0xb0 fs/read_write.c:497
 vfs_write fs/read_write.c:559 [inline]
 vfs_write+0x189/0x380 fs/read_write.c:543
 ksys_write+0xc5/0x1a0 fs/read_write.c:612
 __do_sys_write fs/read_write.c:624 [inline]
 __se_sys_write fs/read_write.c:621 [inline]
 __x64_sys_write+0x49/0x60 fs/read_write.c:621
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88811cd766e8 of 8 bytes by task 13659 on cpu 1:
 __mpage_writepage+0xb5/0xdc0 fs/mpage.c:517
 write_cache_pages+0x400/0xa10 mm/page-writeback.c:2238
 mpage_writepages+0xab/0x180 fs/mpage.c:730
 fat_writepages+0x2a/0x40 fs/fat/inode.c:205
 do_writepages+0x6b/0x170 mm/page-writeback.c:2344
 __filemap_fdatawrite_range+0x1bb/0x220 mm/filemap.c:421
 generic_fadvise+0x47b/0x490 mm/fadvise.c:115
 vfs_fadvise+0x8a/0x90 mm/fadvise.c:187
 ksys_fadvise64_64+0x5b/0xa0 mm/fadvise.c:201
 __do_sys_fadvise64 mm/fadvise.c:216 [inline]
 __se_sys_fadvise64 mm/fadvise.c:214 [inline]
 __x64_sys_fadvise64+0x5a/0x70 mm/fadvise.c:214
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 13659 Comm: syz-executor.0 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (7):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci2-upstream-kcsan-gce 2020/06/15 08:08 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 8e3ab941 .config console log report
ci2-upstream-kcsan-gce 2020/06/07 20:58 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 7751efd0 .config console log report
ci2-upstream-kcsan-gce 2020/06/05 01:22 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 2420d1bc .config console log report
ci2-upstream-kcsan-gce 2020/05/26 17:21 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 9072c126 .config console log report
ci2-upstream-kcsan-gce 2020/05/24 12:31 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 ce7ca010 .config console log report
ci2-upstream-kcsan-gce 2020/05/18 22:14 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 684d3606 .config console log report
ci2-upstream-kcsan-gce 2020/05/15 12:33 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 d7f9fffa .config console log report
* Struck through repros no longer work on HEAD.