---

yaml
---
r: 163797
b: refs/heads/master
c: cdf8073
h: refs/heads/master
i:
  163795: ce5f56b
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ec60a3fe478c0fc6d109eb5840b435ecee4d132b
+refs/heads/master: cdf8073d6b2c6c5a3cd6ce0e6c1297157f7f99ba

trunk/kernel/perf_counter.c

@@ -4208,8 +4208,8 @@ perf_counter_alloc(struct perf_counter_attr *attr,
 static int perf_copy_attr(struct perf_counter_attr __user *uattr,
 			  struct perf_counter_attr *attr)
 {
-	int ret;
 	u32 size;
+	int ret;
 
 	if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0))
 		return -EFAULT;
@@ -4234,19 +4234,19 @@ static int perf_copy_attr(struct perf_counter_attr __user *uattr,
 
 	/*
 	 * If we're handed a bigger struct than we know of,
-	 * ensure all the unknown bits are 0.
+	 * ensure all the unknown bits are 0 - i.e. new
+	 * user-space does not rely on any kernel feature
+	 * extensions we dont know about yet.
 	 */
 	if (size > sizeof(*attr)) {
-		unsigned long val;
-		unsigned long __user *addr;
-		unsigned long __user *end;
+		unsigned char __user *addr;
+		unsigned char __user *end;
+		unsigned char val;
 
-		addr = PTR_ALIGN((void __user *)uattr + sizeof(*attr),
-				sizeof(unsigned long));
-		end  = PTR_ALIGN((void __user *)uattr + size,
-				sizeof(unsigned long));
+		addr = (void __user *)uattr + sizeof(*attr);
+		end  = (void __user *)uattr + size;
 
-		for (; addr < end; addr += sizeof(unsigned long)) {
+		for (; addr < end; addr++) {
 			ret = get_user(val, addr);
 			if (ret)
 				return ret;