gallium: Fix uninitialized variable warning in compute test.

[mesa.git] / src / gallium / auxiliary / os / os_memory_aligned.h

diff --git a/src/gallium/auxiliary/os/os_memory_aligned.h b/src/gallium/auxiliary/os/os_memory_aligned.h
index d4528f73196a6c9938f7ca27da807646d1d57bc5..df398a32bfdbd3af9124b73a54dff7efc64ade40 100644 (file)
--- a/src/gallium/auxiliary/os/os_memory_aligned.h
+++ b/src/gallium/auxiliary/os/os_memory_aligned.h
@@ -39,19 +39,45 @@
 #include "pipe/p_compiler.h"
 
 
+
+/**
+ * Add two size_t values with integer overflow check.
+ * TODO: leverage __builtin_add_overflow where available
+ */
+static inline bool
+add_overflow_size_t(size_t a, size_t b, size_t *res)
+{
+   *res = a + b;
+   return *res < a || *res < b;
+}
+
+
 /**
  * Return memory on given byte alignment
  */
-static INLINE void *
-os_malloc_aligned(size_t size, uint alignment)
+static inline void *
+os_malloc_aligned(size_t size, size_t alignment)
 {
    char *ptr, *buf;
+   size_t alloc_size;
+
+   /*
+    * Calculate
+    *
+    *   alloc_size = size + alignment + sizeof(void *)
+    *
+    * while checking for overflow.
+    */
+   if (add_overflow_size_t(size, alignment, &alloc_size) ||
+       add_overflow_size_t(alloc_size, sizeof(void *), &alloc_size)) {
+      return NULL;
+   }
 
-   ptr = (char *) os_malloc(size + alignment + sizeof(void *));
+   ptr = (char *) os_malloc(alloc_size);
    if (!ptr)
       return NULL;
 
-   buf = (char *)(((uintptr_t)ptr + sizeof(void *) + alignment - 1) & ~(alignment - 1));
+   buf = (char *)(((uintptr_t)ptr + sizeof(void *) + alignment - 1) & ~((uintptr_t)(alignment - 1)));
    *(char **)(buf - sizeof(void *)) = ptr;
 
    return buf;
@@ -59,9 +85,9 @@ os_malloc_aligned(size_t size, uint alignment)
 
 
 /**
- * Free memory returned by align_malloc().
+ * Free memory returned by os_malloc_aligned().
  */
-static INLINE void
+static inline void
 os_free_aligned(void *ptr)
 {
    if (ptr) {