syzbot


KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (4)

Status: auto-closed as invalid on 2022/01/24 21:33
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 364d, last: 342d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages 3 543d 567d 0/24 auto-closed as invalid on 2021/07/08 08:36
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (3) 13 402d 461d 0/24 auto-closed as invalid on 2021/11/26 15:32
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (6) 5 202d 203d 0/24 closed as invalid on 2022/05/13 11:20
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (2) 2 497d 501d 0/24 auto-closed as invalid on 2021/08/23 09:16
upstream KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages (5) 2 297d 299d 0/24 auto-closed as invalid on 2022/03/11 03:48

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages

write to 0xffff88813387ab48 of 8 bytes by task 6747 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 0xffff88813387ab48 of 8 bytes by task 6751 on cpu 1:
 i_size_read include/linux/fs.h:891 [inline]
 ext4_readpage_limit fs/ext4/readpage.c:221 [inline]
 ext4_mpage_readpages+0x395/0x1080 fs/ext4/readpage.c:265
 ext4_readahead+0x99/0xa0 fs/ext4/inode.c:3199
 read_pages+0xba/0x5f0 mm/readahead.c:129
 page_cache_ra_unbounded+0x16a/0x430 mm/readahead.c:210
 ondemand_readahead+0x4f8/0x700
 page_cache_sync_ra+0xaf/0xe0 mm/readahead.c:579
 page_cache_sync_readahead include/linux/pagemap.h:1029 [inline]
 filemap_get_pages mm/filemap.c:2556 [inline]
 filemap_read+0x3eb/0x16d0 mm/filemap.c:2642
 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: 0x000000000050a000 -> 0x0000000000519000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 6751 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 (6):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/12/20 21:25 upstream 86085fe79e3c 62bd192b .config log report info KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
ci2-upstream-kcsan-gce 2021/12/20 05:11 upstream a76c3d035872 44068e19 .config log report info KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
ci2-upstream-kcsan-gce 2021/12/19 09:08 upstream 3f667b5d4053 44068e19 .config log report info KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
ci2-upstream-kcsan-gce 2021/12/18 17:11 upstream 9eaa88c7036e 44068e19 .config log report info KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
ci2-upstream-kcsan-gce 2021/11/29 11:31 upstream d58071a8a76d 63eeac02 .config log report info KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
ci2-upstream-kcsan-gce 2021/11/29 10:32 upstream d06c942efea4 63eeac02 .config log report info KCSAN: data-race in ext4_dio_write_end_io / ext4_mpage_readpages
* Struck through repros no longer work on HEAD.