syzbot


KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent (3)

Status: auto-closed as invalid on 2021/05/17 10:01
Subsystems: ext4
[Documentation on labels]
First crash: 1100d, last: 1100d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent (2) ext4 2 1194d 1201d 0/26 auto-closed as invalid on 2021/02/11 08:14
upstream KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent (6) ext4 1 867d 867d 0/26 auto-closed as invalid on 2022/01/05 07:12
upstream KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent (4) ext4 2 1059d 1063d 0/26 auto-closed as invalid on 2021/06/26 18:17
upstream KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent (5) ext4 4 972d 1017d 0/26 auto-closed as invalid on 2021/09/22 04:33
upstream KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent ext4 1 1251d 1225d 0/26 auto-closed as invalid on 2020/12/21 12:00

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent

write to 0xffff8881417bd468 of 8 bytes by task 6107 on cpu 1:
 __es_find_extent_range+0x28e/0x330 fs/ext4/extents_status.c:298
 __es_scan_range fs/ext4/extents_status.c:347 [inline]
 ext4_es_scan_range+0x94/0x140 fs/ext4/extents_status.c:371
 ext4_map_blocks+0xaad/0xff0 fs/ext4/inode.c:704
 mpage_map_one_extent+0x10d/0x3a0 fs/ext4/inode.c:2397
 mpage_map_and_submit_extent fs/ext4/inode.c:2450 [inline]
 ext4_writepages+0xa51/0x1e70 fs/ext4/inode.c:2802
 do_writepages+0x7b/0x150 mm/page-writeback.c:2352
 __filemap_fdatawrite_range+0x19d/0x1d0 mm/filemap.c:424
 file_write_and_wait_range+0x9f/0x120 mm/filemap.c:763
 ext4_sync_file+0x105/0x6e0 fs/ext4/fsync.c:151
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2843 [inline]
 ext4_buffered_write_iter+0x38f/0x3e0 fs/ext4/file.c:277
 ext4_file_write_iter+0x48a/0x10b0 fs/ext4/file.c:502
 call_write_iter include/linux/fs.h:1977 [inline]
 new_sync_write fs/read_write.c:518 [inline]
 vfs_write+0x6f9/0x7e0 fs/read_write.c:605
 ksys_write+0xce/0x180 fs/read_write.c:658
 __do_sys_write fs/read_write.c:670 [inline]
 __se_sys_write fs/read_write.c:667 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:667
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881417bd468 of 8 bytes by task 6089 on cpu 0:
 ext4_es_lookup_extent+0xac/0x500 fs/ext4/extents_status.c:937
 ext4_da_map_blocks fs/ext4/inode.c:1715 [inline]
 ext4_da_get_block_prep+0x14e/0x9b0 fs/ext4/inode.c:1836
 ext4_block_write_begin+0x414/0xc20 fs/ext4/inode.c:1078
 ext4_da_write_begin+0x50f/0xaf0 fs/ext4/inode.c:3017
 generic_perform_write+0x196/0x3a0 mm/filemap.c:3575
 ext4_buffered_write_iter+0x2e5/0x3e0 fs/ext4/file.c:269
 ext4_file_write_iter+0x48a/0x10b0 fs/ext4/file.c:502
 call_write_iter include/linux/fs.h:1977 [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+0x40a/0x750 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+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x7a6/0xe20 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 6089 Comm: syz-executor.5 Tainted: G        W         5.12.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/04/11 22:52 upstream 7d900724913c 6a81331a .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __es_find_extent_range / ext4_es_lookup_extent
* Struck through repros no longer work on HEAD.