[v6.1] WARNING: suspicious RCU usage in get_callchain_entry

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6741e066ec76 Linux 6.1.87
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1200a087180000
kernel config: https://syzkaller.appspot.com/x/.config?x=3fc2f61bd0ae457
dashboard link: https://syzkaller.appspot.com/bug?extid=a7ca37e23072f6e28af5
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b606a22ddf4b/disk-6741e066.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e31c21737449/vmlinux-6741e066.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ee0cb8c049e9/bzImage-6741e066.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a7ca37...@syzkaller.appspotmail.com

=============================
WARNING: suspicious RCU usage
6.1.87-syzkaller #0 Not tainted
-----------------------------
kernel/events/callchain.c:161 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz-executor.0/4143:
#0: ffffffff8d12b540 (rcu_read_lock_trace){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8d12b540 (rcu_read_lock_trace){....}-{0:0}, at: rcu_read_lock_trace+0x37/0x70 include/linux/rcupdate_trace.h:57

stack backtrace:
CPU: 1 PID: 4143 Comm: syz-executor.0 Not tainted 6.1.87-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
lockdep_rcu_suspicious+0x21c/0x330 kernel/locking/lockdep.c:6592
get_callchain_entry+0x2ac/0x3c0 kernel/events/callchain.c:161
get_perf_callchain+0xe6/0x810 kernel/events/callchain.c:187
__bpf_get_stack+0x378/0x570 kernel/bpf/stackmap.c:438
____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1877 [inline]
bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1867
bpf_prog_b8a90dd1efcc4ad9+0x3d/0x41
bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
__bpf_prog_run include/linux/filter.h:603 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
bpf_prog_run_pin_on_cpu+0x62/0x130 include/linux/filter.h:627
bpf_prog_test_run_syscall+0x312/0x4d0 net/bpf/test_run.c:1629
bpf_prog_test_run+0x32f/0x3a0 kernel/bpf/syscall.c:3670
__sys_bpf+0x3eb/0x6c0 kernel/bpf/syscall.c:5023
__do_sys_bpf kernel/bpf/syscall.c:5109 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5107 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5107
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f89f6e7dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f89f7b6a0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f89f6fabf80 RCX: 00007f89f6e7dea9
RDX: 000000000000000c RSI: 00000000200004c0 RDI: 000000000000000a
RBP: 00007f89f6eca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f89f6fabf80 R15: 00007ffc994174e8
</TASK>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 6741e066ec76 Linux 6.1.87
git tree: linux-6.1.y

console output: https://syzkaller.appspot.com/x/log.txt?x=11874890980000

kernel config: https://syzkaller.appspot.com/x/.config?x=3fc2f61bd0ae457
dashboard link: https://syzkaller.appspot.com/bug?extid=a7ca37e23072f6e28af5
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13e5f237180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=163a46d8980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b606a22ddf4b/disk-6741e066.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e31c21737449/vmlinux-6741e066.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ee0cb8c049e9/bzImage-6741e066.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a7ca37...@syzkaller.appspotmail.com

=============================
WARNING: suspicious RCU usage
6.1.87-syzkaller #0 Not tainted
-----------------------------
kernel/events/callchain.c:161 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1

1 lock held by syz-executor694/3541:

#0: ffffffff8d12b540 (rcu_read_lock_trace){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8d12b540 (rcu_read_lock_trace){....}-{0:0}, at: rcu_read_lock_trace+0x37/0x70 include/linux/rcupdate_trace.h:57

stack backtrace:

CPU: 0 PID: 3541 Comm: syz-executor694 Not tainted 6.1.87-syzkaller #0

RIP: 0033:0x7fdcd878d669
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc652e2d48 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007ffc652e2f18 RCX: 00007fdcd878d669

RDX: 000000000000000c RSI: 00000000200004c0 RDI: 000000000000000a

RBP: 00007fdcd8800610 R08: 00007ffc652e2f18 R09: 00007ffc652e2f18
R10: 00007


---
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