KASAN: user-memory-access Read in preempt_schedule_common

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c5c17547b778 Merge tag 'net-5.16-rc3' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1039f2deb00000
kernel config: https://syzkaller.appspot.com/x/.config?x=75f05fb8d1a152d3
dashboard link: https://syzkaller.appspot.com/bug?extid=1e46367ea3e95c2a97a3
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
CC: [ak...@linux-foundation.org linux-...@vger.kernel.org linu...@kvack.org]

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+1e4636...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: user-memory-access in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: user-memory-access in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
BUG: KASAN: user-memory-access in test_ti_thread_flag include/linux/thread_info.h:118 [inline]
BUG: KASAN: user-memory-access in need_resched include/linux/sched.h:2120 [inline]
BUG: KASAN: user-memory-access in preempt_schedule_common+0x59/0xc0 kernel/sched/core.c:6427
Read of size 8 at addr 0000000084029d00 by task syz-executor.1/19584

CPU: 1 PID: 19584 Comm: syz-executor.1 Not tainted 5.16.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
__kasan_report mm/kasan/report.c:437 [inline]
kasan_report.cold+0x66/0xdf mm/kasan/report.c:450
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:71 [inline]
test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
test_ti_thread_flag include/linux/thread_info.h:118 [inline]
need_resched include/linux/sched.h:2120 [inline]
preempt_schedule_common+0x59/0xc0 kernel/sched/core.c:6427
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:389 [inline]
zap_pte_range mm/memory.c:1408 [inline]
zap_pmd_range mm/memory.c:1467 [inline]
zap_pud_range mm/memory.c:1496 [inline]
zap_p4d_range mm/memory.c:1517 [inline]
unmap_page_range+0x107c/0x29f0 mm/memory.c:1538
unmap_single_vma+0x198/0x310 mm/memory.c:1583
unmap_vmas+0x16b/0x2f0 mm/memory.c:1615
exit_mmap+0x1d0/0x630 mm/mmap.c:3170
__mmput+0x122/0x4b0 kernel/fork.c:1113
mmput+0x56/0x60 kernel/fork.c:1134
exit_mm kernel/exit.c:507 [inline]
do_exit+0xb27/0x2b40 kernel/exit.c:819
do_group_exit+0x125/0x310 kernel/exit.c:929
get_signal+0x47d/0x2220 kernel/signal.c:2852
arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868
handle_signal_work kernel/entry/common.c:148 [inline]
exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f64b4ce7ae9
Code: Unable to access opcode bytes at RIP 0x7f64b4ce7abf.
RSP: 002b:00007f64b223c218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f64b4dfb028 RCX: 00007f64b4ce7ae9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f64b4dfb02c
RBP: 00007f64b4dfb020 R08: 000000000000000e R09: 0000000000000000
R10: 0000000000000050 R11: 0000000000000246 R12: 00007f64b4dfb02c
R13: 00007ffd3442a1bf R14: 00007f64b223c300 R15: 0000000000022000
</TASK>
==================================================================


---
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 syzk...@googlegroups.com.

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

[syzbot]

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