Messages in this thread | | | From | Alexander Potapenko <> | Date | Tue, 21 Apr 2020 10:00:58 +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 12:33 AM Andrew Morton <akpm@linux-foundation.org> 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. > > > > ... > > > > --- a/fs/binfmt_elf.c > > +++ b/fs/binfmt_elf.c > > @@ -1733,7 +1733,7 @@ static int fill_thread_core_info(struct elf_thread_core_info *t, > > (!regset->active || regset->active(t->task, regset) > 0)) { > > int ret; > > size_t size = regset_size(t->task, regset); > > - void *data = kmalloc(size, GFP_KERNEL); > > + void *data = kzalloc(size, GFP_KERNEL); > > if (unlikely(!data)) > > return 0; > > ret = regset->get(t->task, regset, > > This seems to be a quite easy way of exposing quite a large amount of > kernel memory contents, so I think I'll add a cc:stable to this patch?
Correct. Sorry, I forgot about this.
The reporter is also happy with the Reported-by: tag, so you can ignore the note.
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