syzbot


KCSAN: data-race in copy_page_to_iter / ext4_orphan_del

Status: auto-closed as invalid on 2021/11/06 21:29
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 431d, last: 431d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in copy_page_to_iter / ext4_orphan_del

write to 0xffff88813a54e4e8 of 4 bytes by task 2485 on cpu 1:
 ext4_orphan_del+0x607/0x730 fs/ext4/orphan.c:279
 ext4_evict_inode+0xb1e/0xdb0 fs/ext4/inode.c:318
 evict+0x1c8/0x3c0 fs/inode.c:588
 iput_final fs/inode.c:1664 [inline]
 iput+0x430/0x580 fs/inode.c:1690
 ext4_process_orphan+0x1b5/0x1d0 fs/ext4/orphan.c:360
 ext4_orphan_cleanup+0x627/0x9b0 fs/ext4/orphan.c:474
 ext4_fill_super+0x71af/0x7840 fs/ext4/super.c:4952
 mount_bdev+0x1e8/0x290 fs/super.c:1368
 ext4_mount+0x2d/0x40 fs/ext4/super.c:6506
 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 0xffff88813a54e000 of 1377 bytes by task 1941 on cpu 0:
 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: 0 PID: 1941 Comm: systemd-udevd Not tainted 5.15.0-rc3-syzkaller #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 2021/10/02 21:20 upstream ab2a7a35c4e7 db0f5787 .config log report info KCSAN: data-race in copy_page_to_iter / ext4_orphan_del
* Struck through repros no longer work on HEAD.