kernel panic: corrupted stack end in syscall_exit_to_user_mode

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 38d2b86a665b Add linux-next specific files for 20230208
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11d0039f480000
kernel config: https://syzkaller.appspot.com/x/.config?x=3691b32dd4410e01
dashboard link: https://syzkaller.appspot.com/bug?extid=694d875fe9906819aec8
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
CC: [linux-...@vger.kernel.org lu...@kernel.org pet...@infradead.org tg...@linutronix.de]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0a9d60e90514/disk-38d2b86a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/71311be5f1a1/vmlinux-38d2b86a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a242870cc8eb/bzImage-38d2b86a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+694d87...@syzkaller.appspotmail.com

Kernel panic - not syncing: corrupted stack end detected inside scheduler
CPU: 0 PID: 6063 Comm: syz-executor.0 Not tainted 6.2.0-rc7-next-20230208-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
panic+0x61b/0x6c0 kernel/panic.c:319
schedule_debug kernel/sched/core.c:5862 [inline]
__schedule+0x5953/0x5a60 kernel/sched/core.c:6513
preempt_schedule_irq+0x52/0x90 kernel/sched/core.c:6931
irqentry_exit+0x35/0x80 kernel/entry/common.c:433
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:stack_not_used include/linux/sched/task_stack.h:107 [inline]
RIP: 0010:check_stack_usage kernel/exit.c:772 [inline]
RIP: 0010:do_exit+0x18af/0x2b60 kernel/exit.c:913
Code: 00 fc ff df 4c 8b 6d 20 4c 89 ed e8 1b f5 36 00 48 83 c5 08 48 89 e8 48 c1 e8 03 42 80 3c 30 00 0f 85 2f 0d 00 00 4c 8b 65 00 <31> ff 4c 89 e6 e8 67 f1 36 00 4d 85 e4 74 d2 e8 ed f4 36 00 4c 63
RSP: 0018:ffffc90014affc18 EFLAGS: 00000246
RAX: 1ffff9200295f001 RBX: ffff888085770000 RCX: 0000000000000000
RDX: ffff888085770000 RSI: ffffffff814d78c5 RDI: ffff888085770020
RBP: ffffc90014af8008 R08: 0000000000000005 R09: 0000000000000008
R10: 0000000000000008 R11: 0000000000000000 R12: 0000000000000000
R13: ffffc90014af8000 R14: dffffc0000000000 R15: ffff8880857705f8
do_group_exit+0xd4/0x2a0 kernel/exit.c:1019
get_signal+0x2321/0x25b0 kernel/signal.c:2859
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
__syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297
ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:301
RIP: 0033:0x7efce288d521
Code: Unable to access opcode bytes at 0x7efce288d4f7.
RSP: 002b:00007efce35992f0 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: 0000000000000000 RBX: 00007efce3599700 RCX: 00007efce288d521
RDX: 00007efce35999d0 RSI: 00007efce35992f0 RDI: 00000000003d0f00
RBP: 00007ffda04ab050 R08: 00007efce3599700 R09: 00007efce3599700
R10: 00007efce35999d0 R11: 0000000000000206 R12: 00007ffda04aaebe
R13: 00007ffda04aaebf R14: 00007efce3599300 R15: 0000000000022000
</TASK>
Kernel Offset: disabled
Rebooting in 86400 seconds..
----------------
Code disassembly (best guess), 3 bytes skipped:
0: df 4c 8b 6d fisttps 0x6d(%rbx,%rcx,4)
4: 20 4c 89 ed and %cl,-0x13(%rcx,%rcx,4)
8: e8 1b f5 36 00 callq 0x36f528
d: 48 83 c5 08 add $0x8,%rbp
11: 48 89 e8 mov %rbp,%rax
14: 48 c1 e8 03 shr $0x3,%rax
18: 42 80 3c 30 00 cmpb $0x0,(%rax,%r14,1)
1d: 0f 85 2f 0d 00 00 jne 0xd52
23: 4c 8b 65 00 mov 0x0(%rbp),%r12
* 27: 31 ff xor %edi,%edi <-- trapping instruction
29: 4c 89 e6 mov %r12,%rsi
2c: e8 67 f1 36 00 callq 0x36f198
31: 4d 85 e4 test %r12,%r12
34: 74 d2 je 0x8
36: e8 ed f4 36 00 callq 0x36f528
3b: 4c rex.WR
3c: 63 .byte 0x63


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.