lkml.org 
[lkml]   [2016]   [Dec]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
SubjectRe: CVE-2016-7097 causes acl leak
On Mon, Dec 5, 2016 at 9:16 AM, Mark Salyzyn <salyzyn@android.com> wrote:
> Commit 073931017b49d9458aa351605b43a7e34598caef has several occurrences of
> an acl leak.
>
> posix_acl_update_mode(inose, &mode, &acl);
>
> . . .
>
> posix_acl_release(acl);
>
>
> acl is NULLed in posix_acl_update_mode to signal caller to not update the
> acl; but because it is nulled, it is never released.

I think you blame the wrong commit, this leak exists before that commit.
Looks like we should just release it before NULL'ing.

diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 5955220..edd862a 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -648,8 +648,10 @@ int posix_acl_update_mode(struct inode *inode,
umode_t *mode_p,
error = posix_acl_equiv_mode(*acl, &mode);
if (error < 0)
return error;
- if (error == 0)
+ if (error == 0) {
+ posix_acl_release(*acl);
*acl = NULL;
+ }
if (!in_group_p(inode->i_gid) &&
!capable_wrt_inode_uidgid(inode, CAP_FSETID))
mode &= ~S_ISGID;
\
 
 \ /
  Last update: 2016-12-12 01:35    [W:0.112 / U:0.236 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site