[Syzkaller & bisect] There is WARNING in perf_event_open in v6.7-rc5 kernel

From: Pengfei Xu
Date: Wed Dec 13 2023 - 21:28:27 EST

Hi Peter,

Greeting!

There is WARNING in perf_event_open in v6.7-rc5 kernel.

All detailed info: https://github.com/xupengfe/syzkaller_logs/tree/main/231212_034950_perf_event_open
Syzkaller reproduced code: https://github.com/xupengfe/syzkaller_logs/blob/main/231212_034950_perf_event_open/repro.c
Syzkaller syscall reproduced steps: https://github.com/xupengfe/syzkaller_logs/blob/main/231212_034950_perf_event_open/repro.prog
Kconfig(make olddefconfig): https://github.com/xupengfe/syzkaller_logs/blob/main/231212_034950_perf_event_open/kconfig_origin
Bisect info: https://github.com/xupengfe/syzkaller_logs/blob/main/231212_034950_perf_event_open/bisect_info.log
Issue dmesg: https://github.com/xupengfe/syzkaller_logs/blob/main/231212_034950_perf_event_open/a39b6ac3781d46ba18193c9dbb2110f31e9bffe9_dmesg.log
bzImage: https://github.com/xupengfe/syzkaller_logs/raw/main/231212_034950_perf_event_open/bzImage_a39b6ac3781d46ba18193c9dbb2110f31e9bffe9.tar.gz


Bisected and found related commit:
"
382c27f4ed28 perf: Fix perf_event_validate_size()
"
Revert on top of v6.7-rc5, this issue was gone.

[ 23.133852] ------------[ cut here ]------------
[ 23.134146] WARNING: CPU: 1 PID: 727 at kernel/events/core.c:1950 __do_sys_perf_event_open+0x2ba3/0x2c50
[ 23.134752] Modules linked in:
[ 23.134924] CPU: 1 PID: 727 Comm: repro Not tainted 6.7.0-rc5-a39b6ac3781d+ #1
[ 23.135292] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
[ 23.135882] RIP: 0010:__do_sys_perf_event_open+0x2ba3/0x2c50
[ 23.136212] Code: 48 8d b8 a8 00 00 00 e8 5b 99 bb 03 bf 01 00 00 00 41 89 c5 89 c6 e8 fc d9 c9 ff 41 83 ed 01 0f 84 81 ec ff ff e8 fd d7 c9 ff <0f> 0b e9 75 ec ff ff e8 f1 16 29 00 e9 d1 ec ff ff e8 77 17 29 00
[ 23.137194] RSP: 0018:ffff88800cb27d88 EFLAGS: 00010293
[ 23.137465] RAX: ffff888010ea8000 RBX: ffff88800d44bd40 RCX: ffffffff8196ccf4
[ 23.137832] RDX: 0000000000000000 RSI: ffffffff8196cd03 RDI: 0000000000000005
[ 23.138229] RBP: ffff88800cb27ef8 R08: ffff888010ea8000 R09: fffffbfff11c7a2a
[ 23.138724] R10: 0000000000000001 R11: ffffffff88e3d14f R12: ffff88800d44bd40
[ 23.139126] R13: 00000000ffffffff R14: 0000000000000000 R15: 1ffff11001964fbe
[ 23.139492] FS: 00007fef8c620600(0000) GS:ffff88806cd00000(0000) knlGS:0000000000000000
[ 23.139901] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 23.140223] CR2: 00000000200000c0 CR3: 000000000d90a000 CR4: 0000000000750ef0
[ 23.140619] PKRU: 55555554
[ 23.140778] Call Trace:
[ 23.140920] <TASK>
[ 23.141049] ? show_regs+0xa2/0xb0
[ 23.141236] ? __warn+0xef/0x340
[ 23.141412] ? report_bug+0x2f6/0x570
[ 23.141616] ? __do_sys_perf_event_open+0x2ba3/0x2c50
[ 23.141881] ? report_bug+0x360/0x570
[ 23.142083] ? __do_sys_perf_event_open+0x2ba3/0x2c50
[ 23.142385] ? handle_bug+0xa4/0x130
[ 23.142668] ? exc_invalid_op+0x3a/0x90
[ 23.142956] ? asm_exc_invalid_op+0x1f/0x30
[ 23.143241] ? __do_sys_perf_event_open+0x2b94/0x2c50
[ 23.143506] ? __do_sys_perf_event_open+0x2ba3/0x2c50
[ 23.143788] ? __do_sys_perf_event_open+0x2ba3/0x2c50
[ 23.144089] ? __do_sys_perf_event_open+0x2ba3/0x2c50
[ 23.144397] ? __pfx___do_sys_perf_event_open+0x10/0x10
[ 23.144697] ? trace_hardirqs_on+0x26/0x120
[ 23.144951] __x64_sys_perf_event_open+0xc7/0x160
[ 23.145202] ? syscall_enter_from_user_mode+0x51/0x60
[ 23.145476] do_syscall_64+0x42/0xf0
[ 23.145670] entry_SYSCALL_64_after_hwframe+0x6e/0x76
[ 23.145940] RIP: 0033:0x7fef8c43ee5d
[ 23.146145] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 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 8b 0d 93 af 1b 00 f7 d8 64 89 01 48
[ 23.147095] RSP: 002b:00007ffe0ede25a8 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
[ 23.147633] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fef8c43ee5d
[ 23.148052] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 00000000200000c0
[ 23.148451] RBP: 00007ffe0ede25b0 R08: 0000000000000000 R09: 00007ffe0ede25e0
[ 23.148860] R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe0ede2708
[ 23.149263] R13: 0000000000401b49 R14: 0000000000403e08 R15: 00007fef8c661000
[ 23.149654] </TASK>
[ 23.149775] irq event stamp: 1131
[ 23.149961] hardirqs last enabled at (1139): [<ffffffff81420a0d>] console_unlock+0x22d/0x240
[ 23.150428] hardirqs last disabled at (1148): [<ffffffff814209f2>] console_unlock+0x212/0x240
[ 23.151012] softirqs last enabled at (944): [<ffffffff8556dd60>] __do_softirq+0x4f0/0x791
[ 23.151445] softirqs last disabled at (935): [<ffffffff81266fb1>] irq_exit_rcu+0xc1/0x110
[ 23.151884] ---[ end trace 0000000000000000 ]---


I hope it's helpful.


---

If you don't need the following environment to reproduce the problem or if you
already have one reproduced environment, please ignore the following information.

How to reproduce:
git clone https://gitlab.com/xupengfe/repro_vm_env.git
cd repro_vm_env
tar -xvf repro_vm_env.tar.gz
cd repro_vm_env; ./start3.sh // it needs qemu-system-x86_64 and I used v7.1.0
// start3.sh will load bzImage_2241ab53cbb5cdb08a6b2d4688feb13971058f65 v6.2-rc5 kernel
// You could change the bzImage_xxx as you want
// Maybe you need to remove line "-drive if=pflash,format=raw,readonly=on,file=./OVMF_CODE.fd \" for different qemu version
You could use below command to log in, there is no password for root.
ssh -p 10023 root@localhost

After login vm(virtual machine) successfully, you could transfer reproduced
binary to the vm by below way, and reproduce the problem in vm:
gcc -pthread -o repro repro.c
scp -P 10023 repro root@localhost:/root/

Get the bzImage for target kernel:
Please use target kconfig and copy it to kernel_src/.config
make olddefconfig
make -jx bzImage //x should equal or less than cpu num your pc has

Fill the bzImage file into above start3.sh to load the target kernel in vm.


Tips:
If you already have qemu-system-x86_64, please ignore below info.
If you want to install qemu v7.1.0 version:
git clone https://github.com/qemu/qemu.git
cd qemu
git checkout -f v7.1.0
mkdir build
cd build
yum install -y ninja-build.x86_64
yum -y install libslirp-devel.x86_64
../configure --target-list=x86_64-softmmu --enable-kvm --enable-vnc --enable-gtk --enable-sdl --enable-usb-redir --enable-slirp
make
make install

Best Regards,
Thanks!