glx: Length checking for non-generated single requests (v2) [CVE-2014-8098 7/8]

v2:
Fix single versus vendor-private length checking for ARB_imaging subset
extensions. (Julien Cristau)

v3:
Fix single versus vendor-private length checking for ARB_imaging subset
extensions. (Julien Cristau)

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: Julien Cristau <jcristau@debian.org>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>

1 files changed, 15 insertions, 4 deletions

diff --git a/glx/single2swap.c b/glx/single2swap.c
index 764501f59..53490694b 100644
--- a/glx/single2swap.c
+++ b/glx/single2swap.c
@@ -41,6 +41,7 @@
 int
 __glXDispSwap_FeedbackBuffer(__GLXclientState * cl, GLbyte * pc)
 {
+    ClientPtr client = cl->client;
     GLsizei size;
     GLenum type;
 
@@ -48,6 +49,8 @@ __glXDispSwap_FeedbackBuffer(__GLXclientState * cl, GLbyte * pc)
     __GLXcontext *cx;
     int error;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 8);
+
     __GLX_SWAP_INT(&((xGLXSingleReq *) pc)->contextTag);
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
@@ -77,12 +80,15 @@ __glXDispSwap_FeedbackBuffer(__GLXclientState * cl, GLbyte * pc)
 int
 __glXDispSwap_SelectBuffer(__GLXclientState * cl, GLbyte * pc)
 {
+    ClientPtr client = cl->client;
     __GLXcontext *cx;
     GLsizei size;
 
     __GLX_DECLARE_SWAP_VARIABLES;
     int error;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 4);
+
     __GLX_SWAP_INT(&((xGLXSingleReq *) pc)->contextTag);
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
@@ -109,7 +115,7 @@ __glXDispSwap_SelectBuffer(__GLXclientState * cl, GLbyte * pc)
 int
 __glXDispSwap_RenderMode(__GLXclientState * cl, GLbyte * pc)
 {
-    ClientPtr client;
+    ClientPtr client = cl->client;
     __GLXcontext *cx;
     xGLXRenderModeReply reply;
     GLint nitems = 0, retBytes = 0, retval, newModeCheck;
@@ -120,6 +126,8 @@ __glXDispSwap_RenderMode(__GLXclientState * cl, GLbyte * pc)
     __GLX_DECLARE_SWAP_ARRAY_VARIABLES;
     int error;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 4);
+
     __GLX_SWAP_INT(&((xGLXSingleReq *) pc)->contextTag);
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
@@ -200,7 +208,6 @@ __glXDispSwap_RenderMode(__GLXclientState * cl, GLbyte * pc)
      ** selection array, as per the API for glRenderMode itself.
      */
  noChangeAllowed:;
-    client = cl->client;
     reply = (xGLXRenderModeReply) {
         .type = X_Reply,
         .sequenceNumber = client->sequence,
@@ -224,11 +231,14 @@ __glXDispSwap_RenderMode(__GLXclientState * cl, GLbyte * pc)
 int
 __glXDispSwap_Flush(__GLXclientState * cl, GLbyte * pc)
 {
+    ClientPtr client = cl->client;
     __GLXcontext *cx;
     int error;
 
     __GLX_DECLARE_SWAP_VARIABLES;
 
+    REQUEST_SIZE_MATCH(xGLXSingleReq);
+
     __GLX_SWAP_INT(&((xGLXSingleReq *) pc)->contextTag);
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
@@ -243,12 +253,14 @@ __glXDispSwap_Flush(__GLXclientState * cl, GLbyte * pc)
 int
 __glXDispSwap_Finish(__GLXclientState * cl, GLbyte * pc)
 {
+    ClientPtr client = cl->client;
     __GLXcontext *cx;
-    ClientPtr client;
     int error;
 
     __GLX_DECLARE_SWAP_VARIABLES;
 
+    REQUEST_SIZE_MATCH(xGLXSingleReq);
+
     __GLX_SWAP_INT(&((xGLXSingleReq *) pc)->contextTag);
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
@@ -260,7 +272,6 @@ __glXDispSwap_Finish(__GLXclientState * cl, GLbyte * pc)
     cx->hasUnflushedCommands = GL_FALSE;
 
     /* Send empty reply packet to indicate finish is finished */
-    client = cl->client;
     __GLX_BEGIN_REPLY(0);
     __GLX_PUT_RETVAL(0);
     __GLX_SWAP_REPLY_HEADER();