Save major/minor opcodes in ClientRec for RecordAReply

The record extension needs the major and minor opcodes in the reply hook, but the request buffer may have been freed by the time the hook is invoked. Saving the request major and minor codes as the request is executed avoids fetching from the defunct request buffer. This patch also eliminates the public MinorOpcodeOfRequest function, inlining it into Dispatch. Usages of that function have been replaced with direct access to the new ClientRec field. Signed-off-by: Keith Packard <keithp@keithp.com> Reviewed-by: Jamey Sharp <jamey@minilop.net> (cherry picked from commit fb22a40) Conflicts: include/extension.h
pelya · Dec 21, 2011 · 53e347b · 53e347b
1 parent b736f8c
commit 53e347b
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Showing 7 changed files with 20 additions and 36 deletions.
diff --git a/Xext/security.c b/Xext/security.c
@@ -148,9 +148,7 @@ SecurityLabelInitial(void)
 static _X_INLINE const char *
 SecurityLookupRequestName(ClientPtr client)
 {
-    int major = ((xReq *)client->requestBuffer)->reqType;
-    int minor = MinorOpcodeOfRequest(client);
-    return LookupRequestName(major, minor);
+    return LookupRequestName(client->majorOp, client->minorOp);
 }
 
 

diff --git a/Xext/xselinux_hooks.c b/Xext/xselinux_hooks.c
@@ -263,8 +263,8 @@ SELinuxAudit(void *auditdata,
     if (client) {
 	REQUEST(xReq);
 	if (stuff) {
-	    major = stuff->reqType;
-	    minor = MinorOpcodeOfRequest(client);
+	    major = client->majorOp;
+	    minor = client->minorOp;
 	}
     }
     if (audit->id)

diff --git a/dix/dispatch.c b/dix/dispatch.c
@@ -337,8 +337,6 @@ DisableLimitedSchedulingLatency(void)
 	SmartScheduleLatencyLimited = 0;
 }
 
-#define MAJOROP ((xReq *)client->requestBuffer)->reqType
-
 void
 Dispatch(void)
 {
@@ -419,21 +417,28 @@ Dispatch(void)
 	        }
 
 		client->sequence++;
+		client->majorOp = ((xReq *)client->requestBuffer)->reqType;
+		client->minorOp = 0;
+		if (client->majorOp >= EXTENSION_BASE) {
+		    ExtensionEntry *ext = GetExtensionEntry(client->majorOp);
+		    if (ext)
+			client->minorOp = ext->MinorOpcode(client);
+		}
 #ifdef XSERVER_DTRACE
-		XSERVER_REQUEST_START(LookupMajorName(MAJOROP), MAJOROP,
+		XSERVER_REQUEST_START(LookupMajorName(client->majorOp), client->majorOp,
 			      ((xReq *)client->requestBuffer)->length,
 			      client->index, client->requestBuffer);
 #endif
 		if (result > (maxBigRequestSize << 2))
 		    result = BadLength;
 		else {
-		    result = XaceHookDispatch(client, MAJOROP);
+		    result = XaceHookDispatch(client, client->majorOp);
 		    if (result == Success)
-			result = (* client->requestVector[MAJOROP])(client);
+			result = (* client->requestVector[client->majorOp])(client);
 		    XaceHookAuditEnd(client, result);
 		}
 #ifdef XSERVER_DTRACE
-		XSERVER_REQUEST_DONE(LookupMajorName(MAJOROP), MAJOROP,
+		XSERVER_REQUEST_DONE(LookupMajorName(client->majorOp), client->majorOp,
 			      client->sequence, client->index, result);
 #endif
 
@@ -444,8 +449,8 @@ Dispatch(void)
 		}
 		else if (result != Success)
 		{
-		    SendErrorToClient(client, MAJOROP,
-				      MinorOpcodeOfRequest(client),
+		    SendErrorToClient(client, client->majorOp,
+				      client->minorOp,
 				      client->errorValue, result);
 		    break;
 		}
@@ -466,8 +471,6 @@ Dispatch(void)
     SmartScheduleLatencyLimited = 0;
 }
 
-#undef MAJOROP
-
 static int  VendorRelease = VENDOR_RELEASE;
 static char *VendorString = VENDOR_NAME;
 

diff --git a/dix/extension.c b/dix/extension.c
@@ -228,20 +228,6 @@ StandardMinorOpcode(ClientPtr client)
     return ((xReq *)client->requestBuffer)->data;
 }
 
-unsigned short
-MinorOpcodeOfRequest(ClientPtr client)
-{
-    unsigned char major;
-
-    major = ((xReq *)client->requestBuffer)->reqType;
-    if (major < EXTENSION_BASE)
-	return 0;
-    major -= EXTENSION_BASE;
-    if (major >= NumExtensions)
-	return 0;
-    return (*extensions[major]->MinorOpcode)(client);
-}
-
 void
 CloseDownExtensions(void)
 {

diff --git a/include/dixstruct.h b/include/dixstruct.h
@@ -123,6 +123,7 @@ typedef struct _Client {
 
     DeviceIntPtr clientPtr;
     ClientIdPtr  clientIds;
+    unsigned short majorOp, minorOp;
 }           ClientRec;
 
 /*

diff --git a/include/extension.h b/include/extension.h
@@ -52,8 +52,6 @@ _XFUNCPROTOBEGIN
 
 extern _X_EXPORT unsigned short StandardMinorOpcode(ClientPtr /*client*/);
 
-extern _X_EXPORT unsigned short MinorOpcodeOfRequest(ClientPtr /*client*/);
-
 extern _X_EXPORT Bool EnableDisableExtension(char *name, Bool enable);
 
 extern _X_EXPORT void EnableDisableExtensionError(char *name, Bool enable);

diff --git a/record/record.c b/record/record.c
@@ -554,7 +554,7 @@ RecordARequest(ClientPtr client)
 	    }
 	    else /* extension, check minor opcode */
 	    {
-		int minorop = MinorOpcodeOfRequest(client);
+		int minorop = client->minorOp;
 		int numMinOpInfo;
 		RecordMinorOpPtr pMinorOpInfo = pRCAP->pRequestMinOpInfo;
 
@@ -611,19 +611,17 @@ RecordAReply(CallbackListPtr *pcbl, pointer nulldata, pointer calldata)
     RecordContextPtr pContext;
     RecordClientsAndProtocolPtr pRCAP;
     int eci;
-    int majorop;
     ReplyInfoRec *pri = (ReplyInfoRec *)calldata;
     ClientPtr client = pri->client;
-    REQUEST(xReq);
 
-    majorop = stuff->reqType;
     for (eci = 0; eci < numEnabledContexts; eci++)
     {
 	pContext = ppAllContexts[eci];
 	pRCAP = RecordFindClientOnContext(pContext, client->clientAsMask,
 					  NULL);
 	if (pRCAP)
 	{
+	    int majorop = client->majorOp;
 	    if (pContext->continuedReply)
 	    {
 		RecordAProtocolElement(pContext, client, XRecordFromServer,
@@ -644,7 +642,7 @@ RecordAReply(CallbackListPtr *pcbl, pointer nulldata, pointer calldata)
 		}
 		else /* extension, check minor opcode */
 		{
-		    int minorop = MinorOpcodeOfRequest(client);
+		    int minorop = client->minorOp;
 		    int numMinOpInfo;
 		    RecordMinorOpPtr pMinorOpInfo = pRCAP->pReplyMinOpInfo;
 		    		    assert (pMinorOpInfo);