[syzbot] KMSAN: uninit-value in psi_poll_worker

* [syzbot] KMSAN: uninit-value in psi_poll_worker
@ 2022-08-26  9:19 ` syzbot
  0 siblings, 0 replies; 4+ messages in thread
From: syzbot @ 2022-08-26  9:19 UTC (permalink / raw)
  To: bpf, brauner, cgroups, glider, hannes, linux-kernel, lizefan.x,
	syzkaller-bugs, tj

Hello,

syzbot found the following issue on:

HEAD commit:    3a2b6b904ea7 x86: kmsan: enable KMSAN builds for x86
git tree:       https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=13f51a33080000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8e64bc5364a1307e
dashboard link: https://syzkaller.appspot.com/bug?extid=dd8e45eb61404849cde9
compiler:       clang version 15.0.0 (https://github.com/llvm/llvm-project.git 610139d2d9ce6746b3c617fb3e2f7886272d26ff), GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+dd8e45eb61404849cde9@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in update_triggers kernel/sched/psi.c:525 [inline]
BUG: KMSAN: uninit-value in psi_poll_work kernel/sched/psi.c:626 [inline]
BUG: KMSAN: uninit-value in psi_poll_worker+0x972/0x16a0 kernel/sched/psi.c:648
 update_triggers kernel/sched/psi.c:525 [inline]
 psi_poll_work kernel/sched/psi.c:626 [inline]
 psi_poll_worker+0x972/0x16a0 kernel/sched/psi.c:648
 kthread+0x31b/0x430 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

Uninit was stored to memory at:
 collect_percpu_times+0x193d/0x19a0 kernel/sched/psi.c:355
 psi_poll_work kernel/sched/psi.c:604 [inline]
 psi_poll_worker+0x587/0x16a0 kernel/sched/psi.c:648
 kthread+0x31b/0x430 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

Uninit was stored to memory at:
 collect_percpu_times+0x193d/0x19a0 kernel/sched/psi.c:355
 psi_poll_work kernel/sched/psi.c:604 [inline]
 psi_poll_worker+0x587/0x16a0 kernel/sched/psi.c:648
 kthread+0x31b/0x430 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3258 [inline]
 slab_alloc mm/slub.c:3266 [inline]
 kmem_cache_alloc_trace+0x696/0xdf0 mm/slub.c:3297
 kmalloc include/linux/slab.h:600 [inline]
 psi_cgroup_alloc+0x83/0x250 kernel/sched/psi.c:960
 cgroup_create kernel/cgroup/cgroup.c:5430 [inline]
 cgroup_mkdir+0x10a3/0x3080 kernel/cgroup/cgroup.c:5550
 kernfs_iop_mkdir+0x2ba/0x520 fs/kernfs/dir.c:1185
 vfs_mkdir+0x62a/0x870 fs/namei.c:4013
 do_mkdirat+0x466/0x7b0 fs/namei.c:4038
 __do_sys_mkdirat fs/namei.c:4053 [inline]
 __se_sys_mkdirat fs/namei.c:4051 [inline]
 __x64_sys_mkdirat+0xc4/0x120 fs/namei.c:4051
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 0 PID: 19765 Comm: psimon Not tainted 6.0.0-rc2-syzkaller-47460-g3a2b6b904ea7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
=====================================================

---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

^ permalink raw reply	[flat|nested] 4+ messages in thread