syzbot


KCSAN: data-race in xas_create / xas_find_marked (6)

Status: auto-obsoleted due to no activity on 2024/03/09 19:07
Subsystems: mm fs
[Documentation on labels]
Reported-by: syzbot+d99a3b7070791d35415f@syzkaller.appspotmail.com
First crash: 178d, last: 142d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in xas_create / xas_find_marked (4) fs mm 2 597d 601d 0/27 auto-obsoleted due to no activity on 2022/12/10 21:02
upstream KCSAN: data-race in xas_create / xas_find_marked (2) fs mm 1 973d 973d 0/27 auto-closed as invalid on 2021/11/29 22:24
upstream KCSAN: data-race in xas_create / xas_find_marked (3) fs mm 1 772d 772d 0/27 auto-closed as invalid on 2022/06/19 06:15
upstream KCSAN: data-race in xas_create / xas_find_marked (5) fs mm 3 254d 290d 0/27 auto-obsoleted due to no activity on 2023/11/18 23:30
upstream KCSAN: data-race in xas_create / xas_find_marked fs mm 1 1062d 1062d 0/27 auto-closed as invalid on 2021/09/03 00:06

Sample crash report:
loop3: detected capacity change from 0 to 2048
==================================================================
BUG: KCSAN: data-race in xas_create / xas_find_marked

write to 0xffff888106eae491 of 1 bytes by task 3080 on cpu 1:
 xas_expand lib/xarray.c:612 [inline]
 xas_create+0x656/0xbb0 lib/xarray.c:653
 xas_store+0x78/0xc90 lib/xarray.c:787
 __filemap_add_folio+0x45e/0x730 mm/filemap.c:899
 filemap_add_folio+0x70/0x160 mm/filemap.c:938
 page_cache_ra_unbounded+0x15e/0x2e0 mm/readahead.c:250
 do_page_cache_ra mm/readahead.c:299 [inline]
 force_page_cache_ra mm/readahead.c:330 [inline]
 page_cache_sync_ra+0x24b/0x2a0 mm/readahead.c:689
 page_cache_sync_readahead include/linux/pagemap.h:1300 [inline]
 filemap_get_pages+0x251/0xf90 mm/filemap.c:2498
 filemap_read+0x214/0x680 mm/filemap.c:2594
 blkdev_read_iter+0x217/0x2c0 block/fops.c:757
 call_read_iter include/linux/fs.h:2079 [inline]
 new_sync_read fs/read_write.c:395 [inline]
 vfs_read+0x5ab/0x6a0 fs/read_write.c:476
 ksys_read+0xeb/0x1a0 fs/read_write.c:619
 __do_sys_read fs/read_write.c:629 [inline]
 __se_sys_read fs/read_write.c:627 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:627
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888106eae491 of 1 bytes by task 4862 on cpu 0:
 xas_find_marked+0x419/0x660 lib/xarray.c:1338
 find_get_entry+0x5d/0x290 mm/filemap.c:1961
 filemap_get_folios_tag+0x9e/0x210 mm/filemap.c:2211
 __filemap_fdatawait_range+0x82/0x140 mm/filemap.c:514
 filemap_write_and_wait_range+0x11a/0x210 mm/filemap.c:685
 filemap_write_and_wait include/linux/pagemap.h:64 [inline]
 sync_blockdev block/bdev.c:201 [inline]
 set_blocksize+0x1c5/0x290 block/bdev.c:153
 sb_set_blocksize+0x2d/0xb0 block/bdev.c:164
 ext4_load_super fs/ext4/super.c:5099 [inline]
 __ext4_fill_super fs/ext4/super.c:5227 [inline]
 ext4_fill_super+0xad5/0x39b0 fs/ext4/super.c:5703
 get_tree_bdev+0x250/0x2e0 fs/super.c:1619
 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5735
 vfs_get_tree+0x53/0x1d0 fs/super.c:1784
 do_new_mount+0x227/0x690 fs/namespace.c:3352
 path_mount+0x496/0xb30 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3875
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3875
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x03 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4862 Comm: syz-executor.3 Not tainted 6.8.0-rc2-syzkaller-00419-gb555d191561a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
==================================================================
EXT4-fs (loop3): warning: checktime reached, running e2fsck is recommended
EXT4-fs (loop3): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/02/03 19:06 upstream b555d191561a a67b2c42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_create / xas_find_marked
2024/01/10 11:47 upstream 35f11a3710cd b438bd66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_create / xas_find_marked
2023/12/30 05:13 upstream f016f7547aee fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in xas_create / xas_find_marked
* Struck through repros no longer work on HEAD.