Messages in this thread | | | From | Alexander Potapenko <> | Date | Tue, 21 Apr 2020 14:54:23 +0200 | Subject | Re: [PATCH] fs/binfmt_elf.c: allocate initialized memory in fill_thread_core_info() |
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On Tue, Apr 21, 2020 at 5:42 AM Al Viro <viro@zeniv.linux.org.uk> wrote: > > On Mon, Apr 20, 2020 at 03:41:40PM -0700, Kees Cook wrote: > > On Mon, Apr 20, 2020 at 03:33:52PM -0700, Andrew Morton wrote: > > > On Sun, 19 Apr 2020 12:08:48 +0200 glider@google.com wrote: > > > > > > > KMSAN reported uninitialized data being written to disk when dumping > > > > core. As a result, several kilobytes of kmalloc memory may be written to > > > > the core file and then read by a non-privileged user. > > > > Ewww. That's been there for 12 years. Did something change in > > regset_size() or regset->get()? Do you know what leaves the hole? > > Not lately and I would also like to hear the details; which regset it is? > Should be reasonably easy to find - just memset() the damn thing to something > recognizable, do whatever triggers that KMSAN report and look at that > resulting coredump. >
Seems to be REGSET_XSTATE filled by xstateregs_get(). Is there a ptrace interface also using that function?
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