syzbot


KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner (4)

Status: auto-closed as invalid on 2021/07/06 03:43
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 491d, last: 432d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner (2) 2 676d 689d 0/23 auto-closed as invalid on 2020/11/04 12:23
upstream KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner (3) 1 599d 599d 0/23 auto-closed as invalid on 2021/01/20 08:48
upstream KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner 1 730d 730d 0/23 auto-closed as invalid on 2020/09/10 17:38

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

write to 0xffff888147ce40ac of 4 bytes by task 10977 on cpu 1:
 ns_capable_common kernel/capability.c:377 [inline]
 ns_capable kernel/capability.c:396 [inline]
 capable_wrt_inode_uidgid+0xa5/0x140 kernel/capability.c:509
 generic_permission+0x1b7/0x420 fs/namei.c:422
 do_inode_permission fs/namei.c:453 [inline]
 inode_permission+0x6b/0x290 fs/namei.c:513
 may_open+0x1a7/0x2f0 fs/namei.c:2982
 do_open fs/namei.c:3359 [inline]
 path_openat+0x17b3/0x20b0 fs/namei.c:3494
 do_filp_open+0xd9/0x1f0 fs/namei.c:3521
 do_sys_openat2+0xa3/0x250 fs/open.c:1187
 do_sys_open fs/open.c:1203 [inline]
 __do_sys_open fs/open.c:1211 [inline]
 __se_sys_open fs/open.c:1207 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1207
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888147ce40ac of 4 bytes by task 10978 on cpu 0:
 mm_update_next_owner+0x1d9/0x520 kernel/exit.c:389
 exit_mm+0x358/0x450 kernel/exit.c:501
 do_exit+0x3ff/0x1560 kernel/exit.c:813
 do_group_exit+0xce/0x1a0 kernel/exit.c:923
 get_signal+0xfc3/0x1610 kernel/signal.c:2835
 arch_do_signal_or_restart+0x2a/0x220 arch/x86/kernel/signal.c:789
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x109/0x190 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:301
 do_syscall_64+0x56/0x90 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00404040 -> 0x00404140

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10978 Comm: syz-executor.4 Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (7):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/06/01 03:34 upstream c2131f7e73c9 032639db .config log report info KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner
ci2-upstream-kcsan-gce 2021/05/29 03:14 upstream 5ff2756afde0 858ea628 .config log report info KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner
ci2-upstream-kcsan-gce 2021/05/25 05:10 upstream 1434a3127887 3c7fef33 .config log report info KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner
ci2-upstream-kcsan-gce 2021/05/20 20:11 upstream f01da525b3de c560a65d .config log report info KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner
ci2-upstream-kcsan-gce 2021/05/02 14:46 upstream 17ae69aba89d 77e2b668 .config log report info KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner
ci2-upstream-kcsan-gce 2021/04/15 17:12 upstream 7f75285ca572 c59079a6 .config log report info KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner
ci2-upstream-kcsan-gce 2021/04/02 18:34 upstream 1678e493d530 6a81331a .config log report info KCSAN: data-race in capable_wrt_inode_uidgid / mm_update_next_owner