X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/c7d2c2c6ee645e10cbccdd01c6191873ec77239d..743345f9a4b36f7e2f9ba37691e70c50baecb56e:/iokit/Kernel/IOBufferMemoryDescriptor.cpp

diff --git a/iokit/Kernel/IOBufferMemoryDescriptor.cpp b/iokit/Kernel/IOBufferMemoryDescriptor.cpp
index 046274c59..5641d3b9e 100644
--- a/iokit/Kernel/IOBufferMemoryDescriptor.cpp
+++ b/iokit/Kernel/IOBufferMemoryDescriptor.cpp
@@ -626,6 +626,9 @@ void *
 IOBufferMemoryDescriptor::getBytesNoCopy(vm_size_t start, vm_size_t withLength)
 {
     IOVirtualAddress address;
+
+    if ((start + withLength) < start) return 0;
+
     if (kIOMemoryTypePhysical64 == (_flags & kIOMemoryTypeMask))
 	address = (IOVirtualAddress) _buffer;
     else