Subject: WARNING in tracepoint_add_func

From: syzbot <[email-masked]>
Date: Sun, 28 Jun 2020 04:29:17 -0700

Hello,

syzbot found the following crash on:

HEAD commit:    7a64135f libbpf: Adjust SEC short cut for expected attach ..
git tree:       bpf
console output: https://syzkaller.appspot.com/x/log.txt?x=142782e3100000
kernel config:  https://syzkaller.appspot.com/x/.config?x=dcc6334acae363d4
dashboard link: https://syzkaller.appspot.com/bug?extid=721aa903751db87aa244
compiler:       gcc (GCC) 10.1.0-syz 20200507

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: [email-masked]

------------[ cut here ]------------
WARNING: CPU: 1 PID: 16762 at kernel/tracepoint.c:243 tracepoint_add_func+0x254/0x880 kernel/tracepoint.c:243
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 16762 Comm: syz-executor.4 Not tainted 5.8.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:231
 __warn.cold+0x20/0x45 kernel/panic.c:600
 report_bug+0x1bd/0x210 lib/bug.c:198
 exc_invalid_op+0x24d/0x400 arch/x86/kernel/traps.c:235
 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:563
RIP: 0010:tracepoint_add_func+0x254/0x880 kernel/tracepoint.c:243
Code: 44 24 20 48 8b 5b 08 80 38 00 0f 85 6b 05 00 00 48 8b 44 24 08 48 3b 58 08 0f 85 2d ff ff ff 41 bc ef ff ff ff e8 4c 78 fe ff <0f> 0b e8 45 78 fe ff 44 89 e0 48 83 c4 38 5b 5d 41 5c 41 5d 41 5e
RSP: 0018:ffffc90001497a98 EFLAGS: 00010216
RAX: 000000000000199a RBX: ffffffff89b99040 RCX: ffffc90011df4000
RDX: 0000000000040000 RSI: ffffffff8174d824 RDI: ffff8880979adb30
RBP: ffffffff814f1b80 R08: 0000000000000000 R09: ffffffff89bf9867
R10: 000000000000000a R11: 0000000000000000 R12: 00000000ffffffef
R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880979adb10
 tracepoint_probe_register_prio kernel/tracepoint.c:315 [inline]
 tracepoint_probe_register+0x9c/0xe0 kernel/tracepoint.c:335
 trace_event_reg+0x28f/0x350 kernel/trace/trace_events.c:304
 perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline]
 perf_trace_event_init+0x532/0x9a0 kernel/trace/trace_event_perf.c:204
 perf_trace_init+0x176/0x240 kernel/trace/trace_event_perf.c:228
 perf_tp_event_init+0xa2/0x120 kernel/events/core.c:9330
 perf_try_init_event+0x12a/0x560 kernel/events/core.c:10782
 perf_init_event kernel/events/core.c:10834 [inline]
 perf_event_alloc.part.0+0xdee/0x36f0 kernel/events/core.c:11110
 perf_event_alloc kernel/events/core.c:11489 [inline]
 __do_sys_perf_event_open+0x72c/0x2b50 kernel/events/core.c:11605
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cb19
Code: Bad RIP value.
RSP: 002b:00007f2d99608c78 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00000000004fa640 RCX: 000000000045cb19
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000020000100
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000841 R14: 00000000004cb320 R15: 00007f2d996096d4
Kernel Offset: disabled

---
This bug 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 [email-masked].

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