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KCSAN: data-race in ext4_dio_write_end_io / filemap_read (2)

Status: auto-closed as invalid on 2021/10/23 06:54
Subsystems: ext4
[Documentation on labels]
First crash: 1027d, last: 951d
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 716d 716d 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 1081d 1081d 0/26 auto-closed as invalid on 2021/06/15 12:27
upstream KCSAN: data-race in ext4_dio_write_end_io / filemap_read (3) ext4 8 856d 897d 0/26 auto-closed as invalid on 2022/01/25 16:20

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

write to 0xffff88812fd41a88 of 8 bytes by task 17118 on cpu 1:
 i_size_write include/linux/fs.h:916 [inline]
 ext4_dio_write_end_io+0xd3/0x100 fs/ext4/file.c:399
 iomap_dio_complete+0xb8/0x3c0 fs/iomap/direct-io.c:86
 iomap_dio_rw+0x4e/0x70 fs/iomap/direct-io.c:652
 ext4_dio_write_iter fs/ext4/file.c:568 [inline]
 ext4_file_write_iter+0xa59/0x11f0 fs/ext4/file.c:678
 call_write_iter include/linux/fs.h:2163 [inline]
 do_iter_readv_writev+0x2de/0x380 fs/read_write.c:729
 do_iter_write+0x192/0x5c0 fs/read_write.c:855
 vfs_iter_write+0x4c/0x70 fs/read_write.c:896
 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+0x63e/0xbb0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1314 [inline]
 __se_sys_sendfile64 fs/read_write.c:1300 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1300
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88812fd41a88 of 8 bytes by task 17106 on cpu 0:
 i_size_read include/linux/fs.h:894 [inline]
 filemap_read+0xd55/0x1220 mm/filemap.c:2640
 generic_file_read_iter+0x75/0x2c0 mm/filemap.c:2779
 ext4_file_read_iter+0x1db/0x290
 call_read_iter include/linux/fs.h:2157 [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+0x63e/0xbb0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1314 [inline]
 __se_sys_sendfile64 fs/read_write.c:1300 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1300
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000149000 -> 0x000000000014a200

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 17106 Comm: syz-executor.5 Not tainted 5.15.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/09/18 06:51 upstream 4357f03d6611 70b76c1d .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
2021/09/01 02:27 upstream b91db6a0b52e 7eb7e152 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
2021/07/28 21:41 upstream 4010a528219e 9a4781d4 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in ext4_dio_write_end_io / filemap_read
2021/07/03 18:28 upstream 3dbdb38e2869 55aa55c2 .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.