KCSAN: data-race in generic_file_buffered_read / simple_write_end

Status: auto-closed as invalid on 2020/11/28 15:21
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+90b70e3998542fb36ca4@syzkaller.appspotmail.com
First crash: 2198d, last: 2121d
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in generic_file_buffered_read / simple_write_end (2) fs 6 8 2007d 2077d 0/29 auto-closed as invalid on 2021/03/22 07:07

Sample crash report:
==================================================================
BUG: KCSAN: data-race in generic_file_buffered_read / simple_write_end

write to 0xffff88800f9a87f0 of 8 bytes by task 19046 on cpu 0:
 i_size_write include/linux/fs.h:871 [inline]
 simple_write_end+0x1dc/0x340 fs/libfs.c:589
 generic_perform_write+0x23e/0x3a0 mm/filemap.c:3322
 __generic_file_write_iter+0x15c/0x330 mm/filemap.c:3440
 generic_file_write_iter+0x75/0x130 mm/filemap.c:3472
 call_write_iter include/linux/fs.h:1887 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4b0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x42a/0x780 fs/splice.c:686
 do_splice_from fs/splice.c:764 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:933
 splice_direct_to_actor+0x345/0x650 fs/splice.c:888
 do_splice_direct+0xf5/0x170 fs/splice.c:976
 do_sendfile+0x574/0xb70 fs/read_write.c:1257
 __do_sys_sendfile64 fs/read_write.c:1318 [inline]
 __se_sys_sendfile64 fs/read_write.c:1304 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1304
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88800f9a87f0 of 8 bytes by task 19036 on cpu 1:
 i_size_read include/linux/fs.h:849 [inline]
 generic_file_buffered_read+0x13df/0x2110 mm/filemap.c:2294
 generic_file_read_iter+0x80/0x3d0 mm/filemap.c:2535
 call_read_iter include/linux/fs.h:1881 [inline]
 generic_file_splice_read+0x22a/0x310 fs/splice.c:311
 do_splice_to fs/splice.c:788 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:867
 do_splice_direct+0xf5/0x170 fs/splice.c:976
 do_sendfile+0x574/0xb70 fs/read_write.c:1257
 __do_sys_sendfile64 fs/read_write.c:1318 [inline]
 __se_sys_sendfile64 fs/read_write.c:1304 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1304
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 19036 Comm: syz-executor.0 Not tainted 5.9.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (67):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/10/24 15:20 upstream f11901ed723d a1839e81 .config console log report info ci2-upstream-kcsan-gce
2020/10/21 13:25 upstream c4d6fe731176 99c64d5c .config console log report info ci2-upstream-kcsan-gce
2020/10/21 02:44 upstream c4d6fe731176 ff4a3345 .config console log report info ci2-upstream-kcsan-gce
2020/10/19 23:21 upstream bbe85027ce80 ff4a3345 .config console log report info ci2-upstream-kcsan-gce
2020/10/18 04:00 upstream 9d9af1007bc0 fea47c01 .config console log report info ci2-upstream-kcsan-gce
2020/10/17 15:07 upstream 071a0578b0ce fea47c01 .config console log report info ci2-upstream-kcsan-gce
2020/10/15 21:54 upstream 726eb70e0d34 6e262c73 .config console log report info ci2-upstream-kcsan-gce
2020/10/12 20:48 upstream 1e6d1d96461e d32b0bbf .config console log report info ci2-upstream-kcsan-gce
2020/10/12 16:04 upstream bbf5c979011a d32b0bbf .config console log report info ci2-upstream-kcsan-gce
2020/10/09 09:35 upstream 583090b1b823 fa79ed2a .config console log report info ci2-upstream-kcsan-gce
2020/10/05 23:21 upstream 7575fdda569b 1880b4a9 .config console log report info ci2-upstream-kcsan-gce
2020/10/03 17:50 upstream d3d45f8220d6 1a3f9408 .config console log report info ci2-upstream-kcsan-gce
2020/10/03 05:20 upstream d3d45f8220d6 2653fa43 .config console log report info ci2-upstream-kcsan-gce
2020/10/01 21:15 upstream fcadab740480 9602ddf4 .config console log report info ci2-upstream-kcsan-gce
2020/09/30 22:16 upstream 60e720931556 a9767fb2 .config console log report info ci2-upstream-kcsan-gce
2020/09/30 19:46 upstream 02de58b24d2e a9767fb2 .config console log report info ci2-upstream-kcsan-gce
2020/09/29 18:42 upstream fb0155a09b02 5abc3f1a .config console log report info ci2-upstream-kcsan-gce
2020/09/28 12:42 upstream a1b8638ba132 6bfdbe89 .config console log report info ci2-upstream-kcsan-gce
2020/09/26 15:59 upstream 7c7ec3226f5f 2d5ea0cb .config console log report info ci2-upstream-kcsan-gce
2020/09/26 07:14 upstream 7c7ec3226f5f 4a006f63 .config console log report info ci2-upstream-kcsan-gce
2020/09/25 18:31 upstream 171d4ff79f96 4a006f63 .config console log report info ci2-upstream-kcsan-gce
2020/09/24 17:56 upstream 171d4ff79f96 54289b08 .config console log report info ci2-upstream-kcsan-gce
2020/09/20 19:59 upstream bdcf11de8f77 9564d2e9 .config console log report info ci2-upstream-kcsan-gce
2020/09/20 12:15 upstream 325d0eab4f31 53ce8104 .config console log report info ci2-upstream-kcsan-gce
2020/09/20 10:19 upstream 325d0eab4f31 53ce8104 .config console log report info ci2-upstream-kcsan-gce
2020/09/20 08:58 upstream 325d0eab4f31 53ce8104 .config console log report info ci2-upstream-kcsan-gce
2020/09/20 05:41 upstream 325d0eab4f31 53ce8104 .config console log report info ci2-upstream-kcsan-gce
2020/09/19 23:44 upstream eb5f95f1593f 53ce8104 .config console log report info ci2-upstream-kcsan-gce
2020/09/19 16:48 upstream eb5f95f1593f 53ce8104 .config console log report info ci2-upstream-kcsan-gce
2020/09/19 11:20 upstream eb5f95f1593f 53ce8104 .config console log report info ci2-upstream-kcsan-gce
2020/09/19 10:05 upstream eb5f95f1593f 53ce8104 .config console log report info ci2-upstream-kcsan-gce
2020/09/19 00:24 upstream 92ab97adeefc 53ce8104 .config console log report info ci2-upstream-kcsan-gce
2020/09/18 21:48 upstream 92ab97adeefc 53ce8104 .config console log report info ci2-upstream-kcsan-gce
2020/09/18 15:16 upstream 10b82d517648 38962c8b .config console log report info ci2-upstream-kcsan-gce
2020/09/18 03:39 upstream 4cbffc461ec9 8247808b .config console log report info ci2-upstream-kcsan-gce
2020/09/17 23:18 upstream 4cbffc461ec9 8247808b .config console log report info ci2-upstream-kcsan-gce
2020/09/17 12:49 upstream 5925fa68fe82 8247808b .config console log report info ci2-upstream-kcsan-gce
2020/09/17 06:55 upstream 5925fa68fe82 8247808b .config console log report info ci2-upstream-kcsan-gce
2020/09/17 04:56 upstream 5925fa68fe82 8247808b .config console log report info ci2-upstream-kcsan-gce
2020/09/16 22:15 upstream 5925fa68fe82 77507d02 .config console log report info ci2-upstream-kcsan-gce
2020/09/16 20:50 upstream 5925fa68fe82 77507d02 .config console log report info ci2-upstream-kcsan-gce
2020/09/16 19:25 upstream fc4f28bb3daf 77507d02 .config console log report info ci2-upstream-kcsan-gce
2020/09/16 11:10 upstream fc4f28bb3daf 18d7d030 .config console log report info ci2-upstream-kcsan-gce
2020/09/16 08:35 upstream fc4f28bb3daf 18d7d030 .config console log report info ci2-upstream-kcsan-gce
2020/09/16 07:32 upstream fc4f28bb3daf 18d7d030 .config console log report info ci2-upstream-kcsan-gce
2020/09/16 05:00 upstream fc4f28bb3daf 18d7d030 .config console log report info ci2-upstream-kcsan-gce
2020/09/16 04:38 upstream fc4f28bb3daf 18d7d030 .config console log report info ci2-upstream-kcsan-gce
2020/09/16 01:43 upstream fc4f28bb3daf 18d7d030 .config console log report info ci2-upstream-kcsan-gce
2020/09/15 20:16 upstream fc4f28bb3daf 18d7d030 .config console log report info ci2-upstream-kcsan-gce
2020/09/15 18:25 upstream fc4f28bb3daf 9e681632 .config console log report info ci2-upstream-kcsan-gce
2020/09/14 09:27 upstream 84b134997212 2d3cdd63 .config console log report ci2-upstream-kcsan-gce
2020/09/14 07:50 upstream 84b134997212 2d3cdd63 .config console log report ci2-upstream-kcsan-gce
2020/09/14 04:28 upstream 84b134997212 2d3cdd63 .config console log report ci2-upstream-kcsan-gce
2020/09/14 01:41 upstream 84b134997212 2d3cdd63 .config console log report ci2-upstream-kcsan-gce
2020/09/11 00:19 upstream 581cb3a26baf ac7ca78e .config console log report ci2-upstream-kcsan-gce
2020/09/07 16:42 upstream f4d51dffc6c0 abf9ba4f .config console log report ci2-upstream-kcsan-gce
2020/09/07 01:14 upstream a8205e310011 abf9ba4f .config console log report ci2-upstream-kcsan-gce
2020/09/04 07:13 upstream 59126901f200 abf9ba4f .config console log report ci2-upstream-kcsan-gce
2020/08/31 10:39 upstream f75aef392f86 d5a3ae1f .config console log report ci2-upstream-kcsan-gce
2020/08/30 20:48 upstream dcc5c6f013d8 d5a3ae1f .config console log report ci2-upstream-kcsan-gce
2020/08/28 17:54 upstream 15bc20c6af4c d5a3ae1f .config console log report ci2-upstream-kcsan-gce
2020/08/10 10:43 upstream fc80c51fd4b2 7adc7b65 .config console log report ci2-upstream-kcsan-gce
2020/08/09 22:14 upstream 9420f1ce0186 70301872 .config console log report ci2-upstream-kcsan-gce
2020/08/08 23:26 upstream 06a81c1c7db9 f721e4a0 .config console log report ci2-upstream-kcsan-gce
2020/08/08 00:17 upstream 30185b69a2d5 ff51e522 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.