KCSAN: data-race in generic_file_buffered_read / simple_write_end (2)

Status: auto-closed as invalid on 2021/03/22 07:07
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+166eff7b0c24c5d204e5@syzkaller.appspotmail.com
First crash: 2075d, last: 2003d
▶ ▼ 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 fs 6 67 2117d 2141d 0/29 auto-closed as invalid on 2020/11/28 15:21

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

write to 0xffff88810e58e5d0 of 8 bytes by task 15218 on cpu 1:
 i_size_write include/linux/fs.h:870 [inline]
 simple_write_end+0x2c3/0x420 fs/libfs.c:589
 generic_perform_write+0x23e/0x3a0 mm/filemap.c:3423
 __generic_file_write_iter+0x15c/0x340 mm/filemap.c:3541
 generic_file_write_iter+0x75/0x130 mm/filemap.c:3573
 call_write_iter include/linux/fs.h:1901 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x41a/0x770 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+0x5e0/0xcf0 fs/read_write.c:1257
 __do_sys_sendfile64 fs/read_write.c:1312 [inline]
 __se_sys_sendfile64 fs/read_write.c:1304 [inline]
 __x64_sys_sendfile64+0xa9/0x130 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 0xffff88810e58e5d0 of 8 bytes by task 15263 on cpu 0:
 i_size_read include/linux/fs.h:848 [inline]
 generic_file_buffered_read+0x290/0x9c0 mm/filemap.c:2500
 generic_file_read_iter+0x82/0x3e0 mm/filemap.c:2637
 call_read_iter include/linux/fs.h:1895 [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+0x5e0/0xcf0 fs/read_write.c:1257
 __do_sys_sendfile64 fs/read_write.c:1312 [inline]
 __se_sys_sendfile64 fs/read_write.c:1304 [inline]
 __x64_sys_sendfile64+0xa9/0x130 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: 0 PID: 15263 Comm: syz-executor.5 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/02/15 07:06 upstream f40ddce88593 98682e5e .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in generic_file_buffered_read / simple_write_end
2021/02/13 03:43 upstream dcc0b49040c7 98682e5e .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in generic_file_buffered_read / simple_write_end
2021/02/07 13:49 upstream 825b5991a46e 2ce644fc .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in generic_file_buffered_read / simple_write_end
2021/01/22 08:17 upstream 83d09ad4b950 d4f4eca5 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in generic_file_buffered_read / simple_write_end
2020/12/31 19:35 upstream f6e1ea196492 79264ae3 .config console log report info ci2-upstream-kcsan-gce
2020/12/14 01:40 upstream ec6f5e0e5ca0 8f160dd5 .config console log report info ci2-upstream-kcsan-gce
2020/12/14 01:39 upstream ec6f5e0e5ca0 8f160dd5 .config console log report info ci2-upstream-kcsan-gce
2020/12/05 08:08 upstream b3298500b23f 0ef84591 .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.