Messages in this thread | | | Date | Wed, 14 May 2014 12:38:10 -0400 | From | Sasha Levin <> | Subject | Re: perf: use after free in perf_remove_from_context |
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On 05/14/2014 12:35 PM, Peter Zijlstra wrote: > On Wed, May 14, 2014 at 12:32:26PM -0400, Sasha Levin wrote: >> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 >> >> On 05/14/2014 12:29 PM, Peter Zijlstra wrote: >>> On Mon, May 12, 2014 at 11:42:33AM -0400, Sasha Levin wrote: >>>> Hi all, >>>> >>>> While fuzzing with trinity inside a KVM tools guest running the latest -next kernel I've stumbled on the following spew. Maybe related to the very recent change in freeing on task exit? >>>> >>>> [ 2509.827261] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC [ 2509.830379] Dumping ftrace buffer: [ 2509.830379] (ftrace buffer empty) [ 2509.830379] Modules linked in: [ 2509.830379] CPU: 47 PID: 43306 Comm: trinity-c126 Tainted: G W 3.15.0-rc5-next-20140512-sasha-00019-ga20bc00-dirty #456 >>> >>> Any particular trinity setup? And would you happen to have the seed of that run? >> >> Nothing special about trinity options. 400 threads and blacklisting some of the destructive syscalls (umount, reboot, etc). >> >> I don't have the seed, but that problem did reproduce again tonight so I can test out debug code if you have something in mind. > > Nah, I drew a pretty big blank, which is why I wanted to see if I could reproduce. If you could share your trinity cmdline I'd be much obliged. While I did manage to clone (the repo moved since last time) and build it, I'm not really that handy with it and want to avoid destroying my machine if possible ;-) >
./trinity -xinit_module -xreboot -xshutdown -xunshare -xnfsservctl -xclock_nanosleep -xuselib -xumount -xmount -m --quiet --dangerous -C 400 -l off
Note that I run it as root in a disposable VM. Running that as root on your machine will likely kill it.
Thanks, Sasha -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
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