lkml.org 
[lkml]   [2009]   [Dec]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] avoid out of bounds array reference in save_trace()
From
Date
On Wed, 2009-12-09 at 14:29 -0800, Luck, Tony wrote:
> ia64 found this the hard way (because we currently have a stub for
> save_stack_trace() that does nothing). But it would be a good idea to
> be cautious in case a real save_stack_trace() bailed out with an
> error before it set trace->nr_entries.
>
> Signed-off-by: Tony Luck <tony.luck@intel.com>

Thanks Tony,

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>

> ---
>
> diff --git a/kernel/lockdep.c b/kernel/lockdep.c
> index 03c06af..429540c 100644
> --- a/kernel/lockdep.c
> +++ b/kernel/lockdep.c
> @@ -387,7 +387,8 @@ static int save_trace(struct stack_trace *trace)
> * complete trace that maxes out the entries provided will be reported
> * as incomplete, friggin useless </rant>
> */
> - if (trace->entries[trace->nr_entries-1] == ULONG_MAX)
> + if (trace->nr_entries != 0 &&
> + trace->entries[trace->nr_entries-1] == ULONG_MAX)
> trace->nr_entries--;
>
> trace->max_entries = trace->nr_entries;




\
 
 \ /
  Last update: 2009-12-09 23:37    [W:0.120 / U:0.544 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site