Changeset 93616 in vbox for trunk/src/VBox

Timestamp:

Feb 6, 2022 8:03:47 AM (3 years ago)

Author:

vboxsync

Message:

SUP: Make sure SUPR3PageAllocEx returns zero'ed memory. bugref:10094

Location:

trunk/src/VBox/HostDrivers/Support

Files:

• SUPDrv.cpp (modified) (1 diff)
• SUPLib.cpp (modified) (4 diffs)

trunk/src/VBox/HostDrivers/Support/SUPDrv.cpp

@@ -3811 +3811 @@
         int rc2;
         if (ppvR3)
+        {
+            /* Make sure memory mapped into ring-3 is zero initialized if we can: */
+            if (   ppvR0
+                && !RTR0MemObjWasZeroInitialized(Mem.MemObj))
+            {
+                void *pv = RTR0MemObjAddress(Mem.MemObj);
+                Assert(pv || !ppvR0);
+                if (pv)
+                    RT_BZERO(pv, (size_t)cPages * PAGE_SIZE);
+            }
+
             rc = RTR0MemObjMapUser(&Mem.MapObjR3, Mem.MemObj, (RTR3PTR)-1, 0, RTMEM_PROT_WRITE | RTMEM_PROT_READ, NIL_RTR0PROCESS);
+        }
         else
             Mem.MapObjR3 = NIL_RTR0MEMOBJ;

trunk/src/VBox/HostDrivers/Support/SUPLib.cpp

@@ -1105 +1105 @@
     if (RT_SUCCESS(rc))
     {
+        Assert(ASMMemIsZero(*ppvPages, cPages << PAGE_SHIFT));
         if (!paPages)
             paPages = (PSUPPAGE)alloca(sizeof(paPages[0]) * cPages);
@@ -1135 +1136 @@
     {
         int rc = SUPR3PageAlloc(cPages, 0 /*fFlags*/, ppvPages);
+        Assert(RT_FAILURE(rc) || ASMMemIsZero(*ppvPages, cPages << PAGE_SHIFT));
         if (pR0Ptr)
             *pR0Ptr = NIL_RTR0PTR;
@@ -1186 +1188 @@
                 *ppvPages = pReq->u.Out.pvR3;
                 if (pR0Ptr)
-                    *pR0Ptr   = pReq->u.Out.pvR0;
+                {
+                    *pR0Ptr = pReq->u.Out.pvR0;
+                    Assert(ASMMemIsZero(pReq->u.Out.pvR3, cPages << PAGE_SHIFT));
+#ifdef RT_OS_DARWIN /* HACK ALERT! */
+                    supR3TouchPages(pReq->u.Out.pvR3, cPages);
+#endif
+                }
+                else
+                    RT_BZERO(pReq->u.Out.pvR3, cPages << PAGE_SHIFT);
+
                 if (paPages)
                     for (size_t iPage = 0; iPage < cPages; iPage++)
@@ -1194 +1205 @@
                         Assert(!(paPages[iPage].Phys & ~X86_PTE_PAE_PG_MASK));
                     }
-#ifdef RT_OS_DARWIN /* HACK ALERT! */
-                supR3TouchPages(pReq->u.Out.pvR3, cPages);
-#endif
             }
             else if (   rc == VERR_NOT_SUPPORTED