Re: [x86/kprobes] 413d31338f: kernel_BUG_at_mm/vmalloc.c
From: Masami Hiramatsu
Date: Fri Dec 18 2020 - 07:45:18 EST
Hi,
> +
> static int arch_copy_kprobe(struct kprobe *p)
> {
> struct insn insn;
> kprobe_opcode_t buf[MAX_INSN_SIZE];
> int len;
>
> + memset(&p->ainsn, 0, sizeof(p->ainsn));
Oops, I missed to clear the ainsn.insn here. This must be fixed.
Thanks,
On Fri, 18 Dec 2020 09:02:21 +0800
kernel test robot <oliver.sang@xxxxxxxxx> wrote:
>
> Greeting,
>
> FYI, we noticed the following commit (built with gcc-9):
>
> commit: 413d31338fca081133c508bcabc57854765f43df ("[PATCH 1/1] x86/kprobes: Do not decode opcode in resume_execution()")
> url: https://github.com/0day-ci/linux/commits/Masami-Hiramatsu/x86-kprobes-Classify-opcode-while-preparing-kprobe/20201206-221324
> base: https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git 238c91115cd05c71447ea071624a4c9fe661f970
>
> in testcase: trinity
> version: trinity-static-i386-x86_64-f93256fb_2019-08-28
> with following parameters:
>
> runtime: 300s
>
> test-description: Trinity is a linux system call fuzz tester.
> test-url: http://codemonkey.org.uk/projects/trinity/
>
>
> on test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 2 -m 8G
>
> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
>
>
> +------------------------------------------+------------+------------+
> | | 238c91115c | 413d31338f |
> +------------------------------------------+------------+------------+
> | boot_successes | 8 | 0 |
> | boot_failures | 0 | 8 |
> | kernel_BUG_at_mm/vmalloc.c | 0 | 8 |
> | invalid_opcode:#[##] | 0 | 8 |
> | EIP:vmalloc_to_page | 0 | 8 |
> | Kernel_panic-not_syncing:Fatal_exception | 0 | 8 |
> +------------------------------------------+------------+------------+
>
>
> If you fix the issue, kindly add following tag
> Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
>
>
> [ 8.468076] kernel BUG at mm/vmalloc.c:364!
> [ 8.468257] invalid opcode: 0000 [#1] PREEMPT SMP PTI
> [ 8.468344] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc7-00002-g413d31338fca08 #2
> [ 8.468344] EIP: vmalloc_to_page+0x27/0x107
> [ 8.468344] Code: 89 c8 c3 55 89 c2 89 c1 c1 e9 1e 89 e5 57 56 53 53 a1 64 06 cb c1 89 55 f0 8d 1c c8 89 d0 e8 9d ff ff ff 85 c0 8b 55 f0 75 02 <0f> 0b 8b 03 8b 4b 04 89 c6 81 e6 18 0e 00 00 74 02 0f 0b 89 c3 81
> [ 8.468344] EAX: 00000000 EBX: c1f6a000 ECX: 00000000 EDX: 00000000
> [ 8.468344] ESI: d087bda5 EDI: d087bda5 EBP: d087bce0 ESP: d087bcd0
> [ 8.468344] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010246
> [ 8.468344] CR0: 80050033 CR2: 00000000 CR3: 01f6a000 CR4: 000406b0
> [ 8.468344] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
> [ 8.468344] DR6: fffe0ff0 DR7: 00000400
> [ 8.468344] Call Trace:
> [ 8.468344] __text_poke+0x4c/0x28f
> [ 8.468344] ? insn_get_displacement+0x1b/0xce
> [ 8.468344] ? cmp_ex_sort+0x17/0x17
> [ 8.468344] text_poke+0x35/0x3a
> [ 8.468344] arch_copy_kprobe+0x12b/0x148
> [ 8.468344] arch_prepare_kprobe+0x48/0x6a
> [ 8.468344] register_kprobe+0x27f/0x374
> [ 8.468344] __register_trace_kprobe+0x6e/0x73
> [ 8.468344] register_trace_kprobe+0x140/0x282
> [ 8.468344] ? traceprobe_set_print_fmt+0x40/0x58
> [ 8.468344] trace_kprobe_create+0x33e/0x3c3
> [ 8.468344] ? __kmalloc+0xc1/0xcd
> [ 8.468344] ? argv_split+0x5b/0xb9
> [ 8.468344] ? trace_kprobe_create+0x3c3/0x3c3
> [ 8.468344] create_or_delete_trace_kprobe+0x1b/0x27
> [ 8.468344] trace_run_command+0x48/0x6b
> [ 8.468344] trace_kprobe_run_command+0xf/0x11
> [ 8.468344] dynevent_create+0xb/0xd
> [ 8.468344] kprobe_event_gen_test_init+0x82/0x1e2
> [ 8.468344] ? kprobe_event_cmd_init+0x13/0x13
> [ 8.468344] ? init_trace_printk+0xf/0xf
> [ 8.468344] do_one_initcall+0xaa/0x1d4
> [ 8.468344] ? rdinit_setup+0x21/0x21
> [ 8.468344] ? trace_initcall_level+0x72/0x76
> [ 8.468344] do_initcalls+0xa8/0xc8
> [ 8.468344] kernel_init_freeable+0x94/0xb9
> [ 8.468344] ? rest_init+0xce/0xce
> [ 8.468344] kernel_init+0x8/0xe4
> [ 8.468344] ret_from_fork+0x1c/0x28
> [ 8.468344] Modules linked in:
> [ 8.476471] ---[ end trace 543d3449d7fd5d3a ]---
>
>
> To reproduce:
>
> # build kernel
> cd linux
> cp config-5.9.0-rc7-00002-g413d31338fca08 .config
> make HOSTCC=gcc-9 CC=gcc-9 ARCH=i386 olddefconfig prepare modules_prepare bzImage
>
> git clone https://github.com/intel/lkp-tests.git
> cd lkp-tests
> bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email
>
>
>
> Thanks,
> Oliver Sang
>
--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>