Re: Kernel oops+crash on repeated auditd restarts

[Eric Paris <eparis@redhat.com>]

That patch fixes a BUG() .  The report has a NULL ptr deref and some
apparent list correuption....  Sadly they aren't the same....

On Wed, 2012-03-28 at 15:42 -0700, Peter Moody wrote:
> fyi: this patch [1] seems to fix the issue for me. The explanation in
> the subject would reliably oops my machine.
> 
> [1] http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=fed474857efbed79cd390d0aee224231ca718f63
> 
> On Wed, Mar 28, 2012 at 1:51 PM, Peter Moody <pmoody@google.com> wrote:
> > Are you still able to reliably reproduce this oops? I'm trying to
> > track this down because this bug (or a very similar bug) is causing
> > some significant headaches here at work, but I haven't had a lot of
> > luck. I'm using usermode linux, though, so that might be interfering
> > with things.
> >
> > On Mon, Mar 5, 2012 at 12:35 AM, Valentin Avram <aval13@gmail.com> wrote:
> >> Finally i found some time and spare server to retest the oops and list_add
> >> corruptions i was getting with the 3.x kernels and auditd 2.1.3.
> >>
> >> I tested now with gentoo's latest stable 3.2.1-gentoo-r2 and kernel.org's
> >> 3.2.9.
> >>
> >> Both get the oops/BUG in the same way and after that, they keep pouring
> >> list_add corruptions with audit_prune_tre(truncated?) and auditctl as comms.
> >>
> >> Since this is not about Gentoo's kernel only, i'll post here the oops in
> >> 3.2.9 and also attach some list_add corruptions.
> >>
> >> 3.2.9 BUG:
> >>
> >> kernel: [  301.240011] BUG: unable to handle kernel NULL pointer dereference
> >> at   (null)
> >> kernel: [  301.240305] IP: [<c1238dd0>] __list_del_entry+0x20/0xe0
> >> kernel: [  301.240481] *pdpt = 0000000000000000 *pde = f000ddc8f000ddc8
> >> kernel: [  301.240698] Oops: 0000 [#1] SMP
> >> kernel: [  301.240910]
> >> kernel: [  301.241030] Pid: 642, comm: fsnotify_mark Not tainted
> >> 3.2.9-drbd-version3 #1 Dell Inc. PowerEdge 2950/0CX396
> >> kernel: [  301.241370] EIP: 0060:[<c1238dd0>] EFLAGS: 00010287 CPU: 6
> >> kernel: [  301.241498] EIP is at __list_del_entry+0x20/0xe0
> >> kernel: [  301.241623] EAX: f4fae544 EBX: f47cffa4 ECX: ffffffff EDX:
> >> 00000000
> >> kernel: [  301.241751] ESI: f4fae544 EDI: f4fae508 EBP: f47cff7c ESP:
> >> f47cff64
> >> kernel: [  301.241879]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
> >> kernel: [  301.242005] Process fsnotify_mark (pid: 642, ti=f47ce000
> >> task=f4f47c00 task.ti=f47ce000)
> >> kernel: [  301.242207] Stack:
> >> kernel: [  301.242327]  c10813c0 f47cffa4 f4f47c00 f4e70888 f47cff7c
> >> f47cffa4 f47cffb8 c10f6976
> >> kernel: [  301.242882]  ffffffc3 f4f47c00 f4f47c00 00000000 f4f47c00
> >> c10530c0 f47cff9c f47cff9c
> >> kernel: [  301.243438]  f4fae544 f4fae544 f4c47f58 00000000 c10f68f0
> >> f47cffe4 c1052834 00000000
> >> kernel: [  301.243995] Call Trace:
> >> kernel: [  301.244119]  [<c10813c0>] ? rcu_check_callbacks+0x110/0x110
> >> kernel: [  301.244248]  [<c10f6976>] fsnotify_mark_destroy+0x86/0x120
> >> kernel: [  301.244377]  [<c10530c0>] ? abort_exclusive_wait+0x80/0x80
> >> kernel: [  301.244504]  [<c10f68f0>] ? fsnotify_put_mark+0x30/0x30
> >> kernel: [  301.244631]  [<c1052834>] kthread+0x74/0x80
> >> kernel: [  301.244756]  [<c10527c0>] ? kthread_flush_work_fn+0x10/0x10
> >> kernel: [  301.244885]  [<c1582ab6>] kernel_thread_helper+0x6/0xd
> >> kernel: [  301.245011] Code: 55 f4 8b 45 f8 e9 75 ff ff ff 90 55 89 e5 53 83
> >> ec 14 8b 08 8b 50 04 81 f9 00 01 10 00 74 24 81 fa 00 02 20 00 0f 84 8e 00
> >> 00 00 <8b> 1a 39 d8 75 62 8b 59 04 39 d8 75 35 89 51 04 89 0a 83 c4 14
> >> kernel: [  301.248195] EIP: [<c1238dd0>] __list_del_entry+0x20/0xe0 SS:ESP
> >> 0068:f47cff64
> >> kernel: [  301.248414] CR2: 0000000000000000
> >> kernel: [  301.248538] ---[ end trace 15082dbfb353f84c ]---
> >>
> >> The kernel was compiled with the following DEBUG support (the bolded one
> >> were requested by Gentoo's Dev:
> >> CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC=y
> >> CONFIG_SLUB_DEBUG=y
> >> CONFIG_HAVE_DMA_API_DEBUG=y
> >> CONFIG_X86_DEBUGCTLMSR=y
> >> CONFIG_PNP_DEBUG_MESSAGES=y
> >> CONFIG_AIC94XX_DEBUG=y
> >> CONFIG_USB_DEBUG=y
> >> CONFIG_DEBUG_KERNEL=y
> >> CONFIG_SCHED_DEBUG=y
> >> CONFIG_DEBUG_RT_MUTEXES=y
> >> CONFIG_DEBUG_PI_LIST=y
> >> CONFIG_DEBUG_BUGVERBOSE=y
> >> CONFIG_DEBUG_INFO=y
> >> CONFIG_DEBUG_MEMORY_INIT=y
> >> CONFIG_DEBUG_LIST=y
> >> CONFIG_DEBUG_STACKOVERFLOW=y
> >> CONFIG_DEBUG_RODATA=y
> >> CONFIG_DEBUG_RODATA_TEST=y
> >>
> >> I attached the kernel config i used for 3.2.9 to generate this oops and
> >> warnings.
> >>
> >> From the list_add warnings that come after, out of 805 warnings i processed,
> >> after masking with XXXXX the PID and next= values that kept changing in
> >> every one, i got 26 types of MD5. I also attached the files relevant as an
> >> archive to this email.
> >>
> >> The Gentoo bug i opened is sleeping, it seems nobody has the time to at
> >> least test to confirm or not the problems i'm seeing (or everybody's
> >> thinking that nobody would restart auditd so often, so the bug it's not that
> >> serious).
> >>
> >>
> >> Thank you for your time.
> >>
> >> On Wed, Feb 8, 2012 at 6:11 PM, Valentin Avram <aval13@gmail.com> wrote:
> >>
> >>
> >> --
> >> Linux-audit mailing list
> >> Linux-audit@redhat.com
> >> https://www.redhat.com/mailman/listinfo/linux-audit
> >
> >
> >
> > --
> > Peter Moody      Google    1.650.253.7306
> > Security Engineer  pgp:0xC3410038
> 
> 
>