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>

5 files changed, 95 insertions, 29 deletions

diff --git a/glx/indirect_texture_compression.c b/glx/indirect_texture_compression.c
index cda765698..1ebf7f3a2 100644
--- a/glx/indirect_texture_compression.c
+++ b/glx/indirect_texture_compression.c
@@ -43,6 +43,8 @@ __glXDisp_GetCompressedTexImage(struct __GLXclientStateRec *cl, GLbyte * pc)
     __GLXcontext *const cx = __glXForceCurrent(cl, req->contextTag, &error);
     ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 8);
+
     pc += __GLX_SINGLE_HDR_SIZE;
     if (cx != NULL) {
         const GLenum target = *(GLenum *) (pc + 0);
@@ -87,6 +89,8 @@ __glXDispSwap_GetCompressedTexImage(struct __GLXclientStateRec *cl, GLbyte * pc)
         __glXForceCurrent(cl, bswap_32(req->contextTag), &error);
     ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 8);
+
     pc += __GLX_SINGLE_HDR_SIZE;
     if (cx != NULL) {
         const GLenum target = (GLenum) bswap_32(*(int *) (pc + 0));
diff --git a/glx/single2.c b/glx/single2.c
index 53b661d20..a6ea614fd 100644
--- a/glx/single2.c
+++ b/glx/single2.c
@@ -45,11 +45,14 @@
 int
 __glXDisp_FeedbackBuffer(__GLXclientState * cl, GLbyte * pc)
 {
+    ClientPtr client = cl->client;
     GLsizei size;
     GLenum type;
     __GLXcontext *cx;
     int error;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 8);
+
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
         return error;
@@ -76,10 +79,13 @@ __glXDisp_FeedbackBuffer(__GLXclientState * cl, GLbyte * pc)
 int
 __glXDisp_SelectBuffer(__GLXclientState * cl, GLbyte * pc)
 {
+    ClientPtr client = cl->client;
     __GLXcontext *cx;
     GLsizei size;
     int error;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 4);
+
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
         return error;
@@ -104,7 +110,7 @@ __glXDisp_SelectBuffer(__GLXclientState * cl, GLbyte * pc)
 int
 __glXDisp_RenderMode(__GLXclientState * cl, GLbyte * pc)
 {
-    ClientPtr client;
+    ClientPtr client = cl->client;
     xGLXRenderModeReply reply;
     __GLXcontext *cx;
     GLint nitems = 0, retBytes = 0, retval, newModeCheck;
@@ -112,6 +118,8 @@ __glXDisp_RenderMode(__GLXclientState * cl, GLbyte * pc)
     GLenum newMode;
     int error;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 4);
+
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
         return error;
@@ -188,7 +196,6 @@ __glXDisp_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,
@@ -207,9 +214,12 @@ __glXDisp_RenderMode(__GLXclientState * cl, GLbyte * pc)
 int
 __glXDisp_Flush(__GLXclientState * cl, GLbyte * pc)
 {
+    ClientPtr client = cl->client;
     __GLXcontext *cx;
     int error;
 
+    REQUEST_SIZE_MATCH(xGLXSingleReq);
+
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
         return error;
@@ -223,10 +233,12 @@ __glXDisp_Flush(__GLXclientState * cl, GLbyte * pc)
 int
 __glXDisp_Finish(__GLXclientState * cl, GLbyte * pc)
 {
+    ClientPtr client = cl->client;
     __GLXcontext *cx;
-    ClientPtr client;
     int error;
 
+    REQUEST_SIZE_MATCH(xGLXSingleReq);
+
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
         return error;
@@ -317,7 +329,7 @@ __glXcombine_strings(const char *cext_string, const char *sext_string)
 int
 DoGetString(__GLXclientState * cl, GLbyte * pc, GLboolean need_swap)
 {
-    ClientPtr client;
+    ClientPtr client = cl->client;
     __GLXcontext *cx;
     GLenum name;
     const char *string;
@@ -327,6 +339,8 @@ DoGetString(__GLXclientState * cl, GLbyte * pc, GLboolean need_swap)
     char *buf = NULL, *buf1 = NULL;
     GLint length = 0;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 4);
+
     /* If the client has the opposite byte order, swap the contextTag and
      * the name.
      */
@@ -343,7 +357,6 @@ DoGetString(__GLXclientState * cl, GLbyte * pc, GLboolean need_swap)
     pc += __GLX_SINGLE_HDR_SIZE;
     name = *(GLenum *) (pc + 0);
     string = (const char *) glGetString(name);
-    client = cl->client;
 
     if (string == NULL)
         string = "";
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();
diff --git a/glx/singlepix.c b/glx/singlepix.c
index 8b6c26187..54ed7fd21 100644
--- a/glx/singlepix.c
+++ b/glx/singlepix.c
@@ -51,6 +51,8 @@ __glXDisp_ReadPixels(__GLXclientState * cl, GLbyte * pc)
     int error;
     char *answer, answerBuffer[200];
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 28);
+
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
         return error;
@@ -100,6 +102,8 @@ __glXDisp_GetTexImage(__GLXclientState * cl, GLbyte * pc)
     char *answer, answerBuffer[200];
     GLint width = 0, height = 0, depth = 1;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 20);
+
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
         return error;
@@ -157,6 +161,8 @@ __glXDisp_GetPolygonStipple(__GLXclientState * cl, GLbyte * pc)
     GLubyte answerBuffer[200];
     char *answer;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 4);
+
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
         return error;
@@ -217,15 +223,13 @@ GetSeparableFilter(__GLXclientState * cl, GLbyte * pc, GLXContextTag tag)
     compsize = __glGetTexImage_size(target, 1, format, type, width, 1, 1);
     compsize2 = __glGetTexImage_size(target, 1, format, type, height, 1, 1);
 
-    if (compsize < 0)
+    if ((compsize = safe_pad(compsize)) < 0)
         return BadLength;
-    if (compsize2 < 0)
+    if ((compsize2 = safe_pad(compsize2)) < 0)
         return BadLength;
-    compsize = __GLX_PAD(compsize);
-    compsize2 = __GLX_PAD(compsize2);
 
     glPixelStorei(GL_PACK_SWAP_BYTES, swapBytes);
-    __GLX_GET_ANSWER_BUFFER(answer, cl, compsize + compsize2, 1);
+    __GLX_GET_ANSWER_BUFFER(answer, cl, safe_add(compsize, compsize2), 1);
     __glXClearErrorOccured();
     glGetSeparableFilter(*(GLenum *) (pc + 0), *(GLenum *) (pc + 4),
                          *(GLenum *) (pc + 8), answer, answer + compsize, NULL);
@@ -249,7 +253,8 @@ int
 __glXDisp_GetSeparableFilter(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_SINGLE_CONTEXT_TAG(pc);
-
+    ClientPtr client = cl->client;
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 16);
     return GetSeparableFilter(cl, pc + __GLX_SINGLE_HDR_SIZE, tag);
 }
 
@@ -257,7 +262,8 @@ int
 __glXDisp_GetSeparableFilterEXT(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_VENDPRIV_CONTEXT_TAG(pc);
-
+    ClientPtr client = cl->client;
+    REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 16);
     return GetSeparableFilter(cl, pc + __GLX_VENDPRIV_HDR_SIZE, tag);
 }
 
@@ -323,7 +329,8 @@ int
 __glXDisp_GetConvolutionFilter(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_SINGLE_CONTEXT_TAG(pc);
-
+    ClientPtr client = cl->client;
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 16);
     return GetConvolutionFilter(cl, pc + __GLX_SINGLE_HDR_SIZE, tag);
 }
 
@@ -331,7 +338,8 @@ int
 __glXDisp_GetConvolutionFilterEXT(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_VENDPRIV_CONTEXT_TAG(pc);
-
+    ClientPtr client = cl->client;
+    REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 16);
     return GetConvolutionFilter(cl, pc + __GLX_VENDPRIV_HDR_SIZE, tag);
 }
 
@@ -390,7 +398,8 @@ int
 __glXDisp_GetHistogram(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_SINGLE_CONTEXT_TAG(pc);
-
+    ClientPtr client = cl->client;
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 16);
     return GetHistogram(cl, pc + __GLX_SINGLE_HDR_SIZE, tag);
 }
 
@@ -398,7 +407,8 @@ int
 __glXDisp_GetHistogramEXT(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_VENDPRIV_CONTEXT_TAG(pc);
-
+    ClientPtr client = cl->client;
+    REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 16);
     return GetHistogram(cl, pc + __GLX_VENDPRIV_HDR_SIZE, tag);
 }
 
@@ -450,7 +460,8 @@ int
 __glXDisp_GetMinmax(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_SINGLE_CONTEXT_TAG(pc);
-
+    ClientPtr client = cl->client;
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 16);
     return GetMinmax(cl, pc + __GLX_SINGLE_HDR_SIZE, tag);
 }
 
@@ -458,7 +469,8 @@ int
 __glXDisp_GetMinmaxEXT(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_VENDPRIV_CONTEXT_TAG(pc);
-
+    ClientPtr client = cl->client;
+    REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 16);
     return GetMinmax(cl, pc + __GLX_VENDPRIV_HDR_SIZE, tag);
 }
 
@@ -517,7 +529,8 @@ int
 __glXDisp_GetColorTable(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_SINGLE_CONTEXT_TAG(pc);
-
+    ClientPtr client = cl->client;
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 16);
     return GetColorTable(cl, pc + __GLX_SINGLE_HDR_SIZE, tag);
 }
 
@@ -525,6 +538,7 @@ int
 __glXDisp_GetColorTableSGI(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_VENDPRIV_CONTEXT_TAG(pc);
-
+    ClientPtr client = cl->client;
+    REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 16);
     return GetColorTable(cl, pc + __GLX_VENDPRIV_HDR_SIZE, tag);
 }
diff --git a/glx/singlepixswap.c b/glx/singlepixswap.c
index 8dc304fa7..9eff5923d 100644
--- a/glx/singlepixswap.c
+++ b/glx/singlepixswap.c
@@ -53,6 +53,8 @@ __glXDispSwap_ReadPixels(__GLXclientState * cl, GLbyte * pc)
     int error;
     char *answer, answerBuffer[200];
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 28);
+
     __GLX_SWAP_INT(&((xGLXSingleReq *) pc)->contextTag);
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
@@ -114,6 +116,8 @@ __glXDispSwap_GetTexImage(__GLXclientState * cl, GLbyte * pc)
     char *answer, answerBuffer[200];
     GLint width = 0, height = 0, depth = 1;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 20);
+
     __GLX_SWAP_INT(&((xGLXSingleReq *) pc)->contextTag);
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
@@ -184,6 +188,8 @@ __glXDispSwap_GetPolygonStipple(__GLXclientState * cl, GLbyte * pc)
 
     __GLX_DECLARE_SWAP_VARIABLES;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 4);
+
     __GLX_SWAP_INT(&((xGLXSingleReq *) pc)->contextTag);
     cx = __glXForceCurrent(cl, __GLX_GET_SINGLE_CONTEXT_TAG(pc), &error);
     if (!cx) {
@@ -251,15 +257,13 @@ GetSeparableFilter(__GLXclientState * cl, GLbyte * pc, GLXContextTag tag)
     compsize = __glGetTexImage_size(target, 1, format, type, width, 1, 1);
     compsize2 = __glGetTexImage_size(target, 1, format, type, height, 1, 1);
 
-    if (compsize < 0)
+    if ((compsize = safe_pad(compsize)) < 0)
         return BadLength;
-    if (compsize2 < 0)
+    if ((compsize2 = safe_pad(compsize2)) < 0)
         return BadLength;
-    compsize = __GLX_PAD(compsize);
-    compsize2 = __GLX_PAD(compsize2);
 
     glPixelStorei(GL_PACK_SWAP_BYTES, !swapBytes);
-    __GLX_GET_ANSWER_BUFFER(answer, cl, compsize + compsize2, 1);
+    __GLX_GET_ANSWER_BUFFER(answer, cl, safe_add(compsize, compsize2), 1);
     __glXClearErrorOccured();
     glGetSeparableFilter(*(GLenum *) (pc + 0), *(GLenum *) (pc + 4),
                          *(GLenum *) (pc + 8), answer, answer + compsize, NULL);
@@ -285,7 +289,9 @@ int
 __glXDispSwap_GetSeparableFilter(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_SINGLE_CONTEXT_TAG(pc);
+    ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 16);
     return GetSeparableFilter(cl, pc + __GLX_SINGLE_HDR_SIZE, tag);
 }
 
@@ -293,7 +299,9 @@ int
 __glXDispSwap_GetSeparableFilterEXT(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_VENDPRIV_CONTEXT_TAG(pc);
+    ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 16);
     return GetSeparableFilter(cl, pc + __GLX_VENDPRIV_HDR_SIZE, tag);
 }
 
@@ -367,7 +375,9 @@ int
 __glXDispSwap_GetConvolutionFilter(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_SINGLE_CONTEXT_TAG(pc);
+    ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 16);
     return GetConvolutionFilter(cl, pc + __GLX_SINGLE_HDR_SIZE, tag);
 }
 
@@ -375,7 +385,9 @@ int
 __glXDispSwap_GetConvolutionFilterEXT(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_VENDPRIV_CONTEXT_TAG(pc);
+    ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 16);
     return GetConvolutionFilter(cl, pc + __GLX_VENDPRIV_HDR_SIZE, tag);
 }
 
@@ -441,7 +453,9 @@ int
 __glXDispSwap_GetHistogram(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_SINGLE_CONTEXT_TAG(pc);
+    ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 16);
     return GetHistogram(cl, pc + __GLX_SINGLE_HDR_SIZE, tag);
 }
 
@@ -449,7 +463,9 @@ int
 __glXDispSwap_GetHistogramEXT(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_VENDPRIV_CONTEXT_TAG(pc);
+    ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 16);
     return GetHistogram(cl, pc + __GLX_VENDPRIV_HDR_SIZE, tag);
 }
 
@@ -507,7 +523,9 @@ int
 __glXDispSwap_GetMinmax(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_SINGLE_CONTEXT_TAG(pc);
+    ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 16);
     return GetMinmax(cl, pc + __GLX_SINGLE_HDR_SIZE, tag);
 }
 
@@ -515,7 +533,9 @@ int
 __glXDispSwap_GetMinmaxEXT(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_VENDPRIV_CONTEXT_TAG(pc);
+    ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 16);
     return GetMinmax(cl, pc + __GLX_VENDPRIV_HDR_SIZE, tag);
 }
 
@@ -581,7 +601,9 @@ int
 __glXDispSwap_GetColorTable(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_SINGLE_CONTEXT_TAG(pc);
+    ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXSingleReq, 16);
     return GetColorTable(cl, pc + __GLX_SINGLE_HDR_SIZE, tag);
 }
 
@@ -589,6 +611,8 @@ int
 __glXDispSwap_GetColorTableSGI(__GLXclientState * cl, GLbyte * pc)
 {
     const GLXContextTag tag = __GLX_GET_VENDPRIV_CONTEXT_TAG(pc);
+    ClientPtr client = cl->client;
 
+    REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 16);
     return GetColorTable(cl, pc + __GLX_VENDPRIV_HDR_SIZE, tag);
 }