Joseph Qi
2013-Aug-02 07:30 UTC
[Ocfs2-devel] [PATCH] ocfs2: fix possible double free in ocfs2_reflink_xattr_rec
In ocfs2_reflink_xattr_rec(), meta_ac and data_ac are allocated by calling ocfs2_lock_reflink_xattr_rec_allocators(). Once an error occurs when allocating *data_ac, it frees *meta_ac which is allocated before. Here it mistakenly sets meta_ac to NULL but *meta_ac. Then ocfs2_reflink_xattr_rec() will try to free meta_ac again which is already invalid. Signed-off-by: Joseph Qi <joseph.qi at huawei.com> --- fs/ocfs2/xattr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index 87daa44..bd2a1f0 100644 --- a/fs/ocfs2/xattr.c +++ b/fs/ocfs2/xattr.c @@ -6799,7 +6799,7 @@ out: if (ret) { if (*meta_ac) { ocfs2_free_alloc_context(*meta_ac); - meta_ac = NULL; + *meta_ac = NULL; } } -- 1.7.9.7
Jeff Liu
2013-Aug-06 14:43 UTC
[Ocfs2-devel] [PATCH] ocfs2: fix possible double free in ocfs2_reflink_xattr_rec
On 08/02/2013 03:30 PM, Joseph Qi wrote:> In ocfs2_reflink_xattr_rec(), meta_ac and data_ac are allocated by > calling ocfs2_lock_reflink_xattr_rec_allocators(). > Once an error occurs when allocating *data_ac, it frees *meta_ac which > is allocated before. Here it mistakenly sets meta_ac to NULL but > *meta_ac. Then ocfs2_reflink_xattr_rec() will try to free meta_ac again > which is already invalid. > > Signed-off-by: Joseph Qi <joseph.qi at huawei.com>Looks good to me, thanks. Reviewed-by: Jie Liu <jeff.liu at oracle.com>> --- > fs/ocfs2/xattr.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c > index 87daa44..bd2a1f0 100644 > --- a/fs/ocfs2/xattr.c > +++ b/fs/ocfs2/xattr.c > @@ -6799,7 +6799,7 @@ out: > if (ret) { > if (*meta_ac) { > ocfs2_free_alloc_context(*meta_ac); > - meta_ac = NULL; > + *meta_ac = NULL; > } > } >