'halt due to suspicious kernel crash' during poweroff
Posted: Sat Nov 29, 2014 7:33 pmRelated to VirtualBox modules? Kernel version is 3.17.4 gentoo hardened, with linux ZFS (current git) and virtualbox guest additions 4.3.20 added.
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'halt due to suspicious kernel crash' during poweroff
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Posted: Sat Nov 29, 2014 7:33 pmRe: 'halt due to suspicious kernel crash' during poweroff
Posted: Sun Nov 30, 2014 7:51 amthis looks like a use after free bug caught by SANITIZE (do you have it enabled?), probably in vboxguest, but i can tell more if you reproduce this with frame pointers enabled.
Re: 'halt due to suspicious kernel crash' during poweroff
Posted: Sun Nov 30, 2014 8:13 amPaX Team wrote:this looks like a use after free bug caught by SANITIZE (do you have it enabled?), probably in vboxguest, but i can tell more if you reproduce this with frame pointers enabled.
Erp, sorry about the lack of frame pointers.
Seeing it took a good few hours before you guys timezone rolled around I disabled some options as a workaround ... I'll revert to a previous snapshot, alter the frame pointer status, give it a go at reproducing and post the output now.
Re: 'halt due to suspicious kernel crash' during poweroff
Posted: Sun Nov 30, 2014 9:37 amI did have PAX_MEMORY_SANITIZE enabled but I think the culprit is actually CONFIG_PAX_KERNEXEC. I am currently verifying this by recompiling without it... will post an update in a minute.
Here's the panic image with frame pointers .. almost the same as I see it, with the addition of a VBoxGuest_RTHeapSimpleSize entry in the call trace.
Here's the panic image with frame pointers .. almost the same as I see it, with the addition of a VBoxGuest_RTHeapSimpleSize entry in the call trace.
Re: 'halt due to suspicious kernel crash' during poweroff
Posted: Sun Nov 30, 2014 9:51 amcuriousity wrote:I did have PAX_MEMORY_SANITIZE enabled but I think the culprit is actually CONFIG_PAX_KERNEXEC. I am currently verifying this by recompiling without it... will post an update in a minute.
No, that wasn't it. I will try disabling PAX_MEMORY_SANITIZE and re-enabling CONFIG_PAX_KERNEXEC, recompile all the modules again and see what happens.
Re: 'halt due to suspicious kernel crash' during poweroff
Posted: Sun Nov 30, 2014 9:54 amcuriousity wrote:curiousity wrote:I did have PAX_MEMORY_SANITIZE enabled but I think the culprit is actually CONFIG_PAX_KERNEXEC. I am currently verifying this by recompiling without it... will post an update in a minute.
No, that wasn't it. I will try disabling PAX_MEMORY_SANITIZE and re-enabling CONFIG_PAX_KERNEXEC, recompile all the modules again and see what happens.
Actually I will leave PAX_MEMORY_SANITIZE on, but try disabling PAX_MEMORY_STACKLEAK. Also still re-enabling CONFIG_PAX_KERNEXEC.
Re: 'halt due to suspicious kernel crash' during poweroff
Posted: Sun Nov 30, 2014 10:16 amcuriousity wrote:Actually I will leave PAX_MEMORY_SANITIZE on, but try disabling PAX_MEMORY_STACKLEAK. Also still re-enabling CONFIG_PAX_KERNEXEC.
Still fails. Time to try PAX_MEMORY_SANITIZE off, PAX_MEMORY_STACKLEAK on, CONFIG_PAX_KERNEXEC on...
Re: 'halt due to suspicious kernel crash' during poweroff
Posted: Sun Nov 30, 2014 7:23 pmcuriousity wrote:Still fails. Time to try PAX_MEMORY_SANITIZE off, PAX_MEMORY_STACKLEAK on, CONFIG_PAX_KERNEXEC on...
That fixed it again.
So yes, it's dying repeatably on multiple kernel builds if PAX_MEMORY_SANITIZE is enabled, while unloading the vboxguest module.
Is this something I can whitelist around and/or whinge about to the virtualbox people upstream? I'd prefer not to switch the whole option off just to get clean shutdowns happening.
Re: 'halt due to suspicious kernel crash' during poweroff
Posted: Sun Nov 30, 2014 7:29 pmi think the problem is in vboxguest/VBoxGuest-linux.c:vboxguestLinuxTermInputDevice, the call to input_free_device is probably not necessary but you should ask kernel and/or vbox developers to be sure.