lkml.org 
[lkml]   [2015]   [Sep]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2] zram: fix possible use after free in zcomp_create()
On (09/07/15 15:13), Luis Henriques wrote:
> zcomp_create() verifies the success of zcomp_strm_{multi,siggle}_create()
> through comp->stream, which can potentially be pointing to memory that was
> freed if these functions returned an error.
>
> Fixes: beca3ec71fe5 ("zram: add multi stream functionality")
> Cc: stable@vger.kernel.org
> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

Cc Andrew


Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>

-ss

> ---
> Changes since v1:
> * Check zcomp_strm_{multi,siggle}_create() return code instead
> comp->stream (suggested by Sergey)
>
> drivers/block/zram/zcomp.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
> index 965d1afb0eaa..8d2cdfd307db 100644
> --- a/drivers/block/zram/zcomp.c
> +++ b/drivers/block/zram/zcomp.c
> @@ -336,6 +336,7 @@ struct zcomp *zcomp_create(const char *compress, int max_strm)
> {
> struct zcomp *comp;
> struct zcomp_backend *backend;
> + int ret;
>
> backend = find_backend(compress);
> if (!backend)
> @@ -347,10 +348,10 @@ struct zcomp *zcomp_create(const char *compress, int max_strm)
>
> comp->backend = backend;
> if (max_strm > 1)
> - zcomp_strm_multi_create(comp, max_strm);
> + ret = zcomp_strm_multi_create(comp, max_strm);
> else
> - zcomp_strm_single_create(comp);
> - if (!comp->stream) {
> + ret = zcomp_strm_single_create(comp);
> + if (ret) {
> kfree(comp);
> return ERR_PTR(-ENOMEM);
> }
>


\
 
 \ /
  Last update: 2015-09-08 02:21    [W:0.086 / U:0.088 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site