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KCSAN: data-race in ext4_dio_write_end_io / filemap_read (3)

Status: auto-closed as invalid on 2022/01/25 16:20
Subsystems: ext4
[Documentation on labels]
First crash: 868d, last: 827d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in ext4_dio_write_end_io / filemap_read (4) ext4 1 687d 687d 0/26 closed as invalid on 2022/05/13 11:20
upstream KCSAN: data-race in ext4_dio_write_end_io / filemap_read ext4 1 1052d 1052d 0/26 auto-closed as invalid on 2021/06/15 12:27
upstream KCSAN: data-race in ext4_dio_write_end_io / filemap_read (2) ext4 4 922d 998d 0/26 auto-closed as invalid on 2021/10/23 06:54

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ext4_dio_write_end_io / filemap_read

write to 0xffff88813549c7d8 of 8 bytes by task 5211 on cpu 0:
 i_size_write include/linux/fs.h:913 [inline]
 ext4_dio_write_end_io+0xd3/0x100 fs/ext4/file.c:399
 iomap_dio_complete+0xb8/0x3e0 fs/iomap/direct-io.c:77
 iomap_dio_rw+0x56/0x80 fs/iomap/direct-io.c:682
 ext4_dio_write_iter fs/ext4/file.c:568 [inline]
 ext4_file_write_iter+0xac3/0x1200 fs/ext4/file.c:679
 call_write_iter include/linux/fs.h:2162 [inline]
 do_iter_readv_writev+0x2de/0x380 fs/read_write.c:725
 do_iter_write+0x192/0x5c0 fs/read_write.c:851
 vfs_iter_write+0x4c/0x70 fs/read_write.c:892
 iter_file_splice_write+0x43a/0x790 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88813549c7d8 of 8 bytes by task 5226 on cpu 1:
 i_size_read include/linux/fs.h:891 [inline]
 filemap_read+0x1208/0x16d0 mm/filemap.c:2654
 generic_file_read_iter+0x72/0x2a0 mm/filemap.c:2792
 ext4_file_read_iter+0x1db/0x290
 call_read_iter include/linux/fs.h:2156 [inline]
 generic_file_splice_read+0x24f/0x330 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:870
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000000a5000 -> 0x00000000000b4000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5226 Comm: syz-executor.1 Not tainted 5.16.0-rc6-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
2021/12/21 16:20 upstream 6e0567b73052 a938f0b8 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
2021/12/13 04:06 upstream 90d9fbc16b69 49ca1f59 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
2021/11/21 09:48 upstream 923dcc5eb0c1 4eb20a4e .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
2021/11/21 02:18 upstream 61564e7b3abc 4eb20a4e .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
2021/11/20 01:25 upstream 4c388a8e740d 3a9d0024 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
2021/11/15 03:38 upstream ce49bfc8d037 75b04091 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
2021/11/11 08:24 upstream debe436e77c7 75b04091 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
2021/11/10 17:15 upstream cb690f5238d7 75b04091 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
* Struck through repros no longer work on HEAD.