---

yaml --- r: 361545 b: refs/heads/master c: 3118a4f h: refs/heads/master i: 361543: 99d82ef v: v3
git-mirror · Mar 13, 2013 · ea4a807 · ea4a807
1 parent a31a002
commit ea4a807
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Showing 2 changed files with 9 additions and 4 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 2563a4524febe8f4a98e717e02436d1aaf672aa2
+refs/heads/master: 3118a4f652c7b12c752f3222af0447008f9b2368
diff --git a/trunk/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/trunk/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -732,6 +732,8 @@ validate_exec_list(struct drm_i915_gem_exec_object2 *exec,
 		   int count)
 {
 	int i;
+	int relocs_total = 0;
+	int relocs_max = INT_MAX / sizeof(struct drm_i915_gem_relocation_entry);
 
 	for (i = 0; i < count; i++) {
 		char __user *ptr = (char __user *)(uintptr_t)exec[i].relocs_ptr;
@@ -740,10 +742,13 @@ validate_exec_list(struct drm_i915_gem_exec_object2 *exec,
 		if (exec[i].flags & __EXEC_OBJECT_UNKNOWN_FLAGS)
 			return -EINVAL;
 
-		/* First check for malicious input causing overflow */
-		if (exec[i].relocation_count >
-		    INT_MAX / sizeof(struct drm_i915_gem_relocation_entry))
+		/* First check for malicious input causing overflow in
+		 * the worst case where we need to allocate the entire
+		 * relocation tree as a single array.
+		 */
+		if (exec[i].relocation_count > relocs_max - relocs_total)
 			return -EINVAL;
+		relocs_total += exec[i].relocation_count;
 
 		length = exec[i].relocation_count *
 			sizeof(struct drm_i915_gem_relocation_entry);