syzbot


KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent (2)

Status: closed as invalid on 2019/10/18 14:11
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 1084d, last: 1084d
similar bugs (8):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent (4) 1 885d 885d 0/24 auto-closed as invalid on 2020/06/18 13:13
upstream KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent (5) 3 738d 795d 0/24 auto-closed as invalid on 2020/10/30 13:53
upstream KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent (6) 1 688d 665d 0/24 auto-closed as invalid on 2020/12/21 12:01
upstream KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent (3) 5 978d 1065d 0/24 auto-closed as invalid on 2020/04/09 02:07
upstream KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent (8) 6 493d 541d 0/24 auto-closed as invalid on 2021/07/03 03:54
upstream KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent (9) 4 326d 335d 0/24 auto-closed as invalid on 2021/12/17 02:26
upstream KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent 60 1084d 1095d 0/24 closed as invalid on 2019/10/15 15:50
upstream KCSAN: data-race in ext4_es_lookup_extent / ext4_es_lookup_extent (7) 2 627d 648d 0/24 auto-closed as invalid on 2021/02/19 02:54

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

read to 0xffff8882184fbc28 of 8 bytes by task 7302 on cpu 1:
 ext4_es_lookup_extent+0x3ba/0x510 fs/ext4/extents_status.c:950
 ext4_map_blocks+0xc2/0xf70 fs/ext4/inode.c:530
 ext4_getblk+0x30b/0x380 fs/ext4/inode.c:974
 ext4_bread+0x4a/0x190 fs/ext4/inode.c:1024
 __ext4_read_dirblock+0x3e/0x700 fs/ext4/namei.c:112
 ext4_add_entry+0x46b/0x8e0 fs/ext4/namei.c:2214
 ext4_mkdir+0x515/0x820 fs/ext4/namei.c:2778
 vfs_mkdir+0x283/0x390 fs/namei.c:3815
 do_mkdirat+0x1ac/0x1f0 fs/namei.c:3838
 __do_sys_mkdir fs/namei.c:3854 [inline]
 __se_sys_mkdir fs/namei.c:3852 [inline]
 __x64_sys_mkdir+0x40/0x50 fs/namei.c:3852
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8882184fbc28 of 8 bytes by task 7300 on cpu 0:
 ext4_es_lookup_extent+0x3d3/0x510 fs/ext4/extents_status.c:950
 ext4_map_blocks+0xc2/0xf70 fs/ext4/inode.c:530
 ext4_mpage_readpages+0x92b/0x1270 fs/ext4/readpage.c:182
 ext4_readpages+0x92/0xc0 fs/ext4/inode.c:3388
 read_pages+0xa2/0x2d0 mm/readahead.c:126
 __do_page_cache_readahead+0x353/0x390 mm/readahead.c:212
 ra_submit mm/internal.h:62 [inline]
 ondemand_readahead+0x35d/0x710 mm/readahead.c:492
 page_cache_async_readahead+0x22c/0x250 mm/readahead.c:574
 generic_file_buffered_read mm/filemap.c:2079 [inline]
 generic_file_read_iter+0xffc/0x1440 mm/filemap.c:2344
 ext4_file_read_iter fs/ext4/file.c:77 [inline]
 ext4_file_read_iter+0xfa/0x240 fs/ext4/file.c:65
 call_read_iter include/linux/fs.h:1864 [inline]
 new_sync_read+0x389/0x4f0 fs/read_write.c:414
 __vfs_read+0xb1/0xc0 fs/read_write.c:427
 integrity_kernel_read+0xa1/0xe0 security/integrity/iint.c:200

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7300 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2019/10/15 16:18 https://github.com/google/ktsan.git kcsan 81f95ec7998e b5268b89 .config log report
* Struck through repros no longer work on HEAD.