syzbot


KCSAN: data-race in copy_page_to_iter / ext4_fill_super (2)

Status: auto-closed as invalid on 2021/11/23 22:50
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 489d, last: 411d
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in copy_page_to_iter / ext4_fill_super 6 527d 587d 0/24 auto-closed as invalid on 2021/07/31 12:41
upstream KCSAN: data-race in copy_page_to_iter / ext4_fill_super (3) 1 354d 354d 0/24 auto-closed as invalid on 2022/01/19 23:07

Sample crash report:
==================================================================
BUG: KCSAN: data-race in copy_page_to_iter / ext4_fill_super

write to 0xffff88812f67240c of 4 bytes by task 23848 on cpu 0:
 ext4_free_blocks_count_set fs/ext4/ext4.h:3323 [inline]
 ext4_fill_super+0x692c/0x7830 fs/ext4/super.c:4885
 mount_bdev+0x1e8/0x290 fs/super.c:1368
 ext4_mount+0x2d/0x40 fs/ext4/super.c:6515
 legacy_get_tree+0x70/0xc0 fs/fs_context.c:610
 vfs_get_tree+0x4a/0x1a0 fs/super.c:1498
 do_new_mount fs/namespace.c:2988 [inline]
 path_mount+0x11ec/0x1d20 fs/namespace.c:3318
 do_mount fs/namespace.c:3331 [inline]
 __do_sys_mount fs/namespace.c:3539 [inline]
 __se_sys_mount+0x24b/0x2f0 fs/namespace.c:3516
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3516
 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 0xffff88812f672400 of 1024 bytes by task 3012 on cpu 1:
 instrument_copy_to_user include/linux/instrumented.h:119 [inline]
 copyout lib/iov_iter.c:156 [inline]
 copy_page_to_iter_iovec lib/iov_iter.c:228 [inline]
 __copy_page_to_iter lib/iov_iter.c:805 [inline]
 copy_page_to_iter+0x2cb/0x950 lib/iov_iter.c:833
 filemap_read+0xee6/0x1220 mm/filemap.c:2683
 generic_file_read_iter+0x75/0x2c0 mm/filemap.c:2779
 blkdev_read_iter+0xb9/0xf0 block/fops.c:545
 call_read_iter include/linux/fs.h:2157 [inline]
 new_sync_read fs/read_write.c:404 [inline]
 vfs_read+0x66c/0x750 fs/read_write.c:485
 ksys_read+0xd9/0x190 fs/read_write.c:623
 __do_sys_read fs/read_write.c:633 [inline]
 __se_sys_read fs/read_write.c:631 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:631
 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

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3012 Comm: udevd Tainted: G        W         5.15.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (11):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/10/19 22:41 upstream d9abdee5fd5a 466b7db1 .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
ci2-upstream-kcsan-gce 2021/10/08 17:27 upstream 1da38549dd64 efe0f24d .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
ci2-upstream-kcsan-gce 2021/10/06 10:29 upstream 60a9483534ed 0a63fd36 .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
ci2-upstream-kcsan-gce 2021/10/04 16:54 upstream 9e1ff307c779 ce697b49 .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
ci2-upstream-kcsan-gce 2021/09/22 16:28 upstream 92477dd1faa6 8cac236e .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
ci2-upstream-kcsan-gce 2021/09/22 07:44 upstream 92477dd1faa6 169724fe .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
ci2-upstream-kcsan-gce 2021/09/15 09:04 upstream 3ca706c189db 07e953c1 .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
ci2-upstream-kcsan-gce 2021/09/09 13:45 upstream a3fa7a101dcf e2776ee4 .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
ci2-upstream-kcsan-gce 2021/08/30 14:43 upstream 7d2a07b76933 8f58a0ef .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
ci2-upstream-kcsan-gce 2021/08/04 00:35 upstream d5ad8ec3cfb5 6c236867 .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
ci2-upstream-kcsan-gce 2021/08/03 01:56 upstream c500bee1c5b2 6c236867 .config log report info KCSAN: data-race in copy_page_to_iter / ext4_fill_super
* Struck through repros no longer work on HEAD.