diff options
| author | Adam Jackson <ajax@redhat.com> | 2014-11-10 12:13:36 -0500 |
|---|---|---|
| committer | Alan Coopersmith <alan.coopersmith@oracle.com> | 2014-12-08 18:09:49 -0800 |
| commit | 23fe7718bb171e71db2d1a30505c2ca2988799d9 (patch) | |
| tree | ceb80e0703cd96315b0d42d5b7fbaf51bc6e9766 /glx | |
| parent | f4afd53f2aeaddf509bf9f71d1716dd273fd6e14 (diff) | |
glx: Be more paranoid about variable-length requests [CVE-2014-8093 1/6]
If the size computation routine returns -1 we should just reject the
request outright. Clamping it to zero could give an attacker the
opportunity to also mangle cmdlen in such a way that the subsequent
length check passes, and the request would get executed, thus passing
data we wanted to reject to the renderer.
Reviewed-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Julien Cristau <jcristau@debian.org>
Reviewed-by: Michal Srb <msrb@suse.com>
Reviewed-by: Andy Ritger <aritger@nvidia.com>
Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Diffstat (limited to 'glx')
| -rw-r--r-- | glx/glxcmds.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/glx/glxcmds.c b/glx/glxcmds.c index 009fd9be0..ea42e2a01 100644 --- a/glx/glxcmds.c +++ b/glx/glxcmds.c @@ -2062,7 +2062,7 @@ __glXDisp_Render(__GLXclientState * cl, GLbyte * pc) extra = (*entry.varsize) (pc + __GLX_RENDER_HDR_SIZE, client->swapped); if (extra < 0) { - extra = 0; + return BadLength; } if (cmdlen != __GLX_PAD(entry.bytes + extra)) { return BadLength; @@ -2179,7 +2179,7 @@ __glXDisp_RenderLarge(__GLXclientState * cl, GLbyte * pc) extra = (*entry.varsize) (pc + __GLX_RENDER_LARGE_HDR_SIZE, client->swapped); if (extra < 0) { - extra = 0; + return BadLength; } /* large command's header is 4 bytes longer, so add 4 */ if (cmdlen != __GLX_PAD(entry.bytes + 4 + extra)) { |