syzbot


KCSAN: data-race in _copy_to_iter / fat_set_state (10)

Status: moderation: reported on 2024/11/21 22:32
Subsystems: exfat
[Documentation on labels]
Reported-by: syzbot+3b57f2200e201709227f@syzkaller.appspotmail.com
First crash: 1d01h, last: 1d01h
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (6) exfat 4 399d 421d 0/28 auto-obsoleted due to no activity on 2023/11/24 07:27
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (5) exfat 1 465d 465d 0/28 auto-obsoleted due to no activity on 2023/09/19 09:04
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (4) exfat 1 522d 522d 0/28 auto-obsoleted due to no activity on 2023/07/24 15:00
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (9) exfat 1 61d 61d 0/28 auto-obsoleted due to no activity on 2024/10/27 23:03
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (7) exfat 6 266d 326d 0/28 auto-obsoleted due to no activity on 2024/04/05 03:03
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (8) exfat 2 138d 172d 0/28 auto-obsoleted due to no activity on 2024/08/11 01:41
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (3) exfat 1 615d 615d 0/28 auto-obsoleted due to no activity on 2023/04/29 03:39
upstream KCSAN: data-race in _copy_to_iter / fat_set_state (2) exfat 2 743d 770d 0/28 auto-obsoleted due to no activity on 2022/12/15 10:49
upstream KCSAN: data-race in _copy_to_iter / fat_set_state exfat 1 842d 842d 0/28 auto-closed as invalid on 2022/09/08 00:15

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

write to 0xffff888108f92025 of 1 bytes by task 15921 on cpu 1:
 fat_set_state+0x16e/0x1e0
 fat_fill_super+0x1798/0x1bf0 fs/fat/inode.c:1832
 vfat_fill_super+0x24/0x30 fs/fat/namei_vfat.c:1200
 get_tree_bdev_flags+0x29f/0x310 fs/super.c:1636
 get_tree_bdev+0x1f/0x30 fs/super.c:1659
 vfat_get_tree+0x1c/0x30 fs/fat/namei_vfat.c:1205
 vfs_get_tree+0x56/0x1e0 fs/super.c:1814
 do_new_mount+0x227/0x690 fs/namespace.c:3507
 path_mount+0x49b/0xb30 fs/namespace.c:3834
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4057 [inline]
 __se_sys_mount+0x27c/0x2d0 fs/namespace.c:4034
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4034
 x64_sys_call+0x2c84/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888108f92000 of 256 bytes by task 3308 on cpu 0:
 instrument_copy_to_user include/linux/instrumented.h:113 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:30 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:300 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 _copy_to_iter+0x130/0xd00 lib/iov_iter.c:185
 copy_page_to_iter+0x171/0x2b0 lib/iov_iter.c:362
 copy_folio_to_iter include/linux/uio.h:189 [inline]
 filemap_read+0x42d/0x6a0 mm/filemap.c:2698
 blkdev_read_iter+0x20e/0x2c0 block/fops.c:767
 new_sync_read fs/read_write.c:484 [inline]
 vfs_read+0x5dc/0x700 fs/read_write.c:565
 ksys_read+0xe8/0x1b0 fs/read_write.c:708
 __do_sys_read fs/read_write.c:717 [inline]
 __se_sys_read fs/read_write.c:715 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:715
 x64_sys_call+0x2874/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3308 Comm: udevd Not tainted 6.12.0-syzkaller-03657-g43fb83c17ba2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/21 22:31 upstream 43fb83c17ba2 4b25d554 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in _copy_to_iter / fat_set_state
* Struck through repros no longer work on HEAD.