perf probe: Fix memory leak when synthesizing SDT probes

[linux-2.6-microblaze.git] / lib / test_user_copy.c

diff --git a/lib/test_user_copy.c b/lib/test_user_copy.c
index e365ace..5ff04d8 100644 (file)
--- a/lib/test_user_copy.c
+++ b/lib/test_user_copy.c
@@ -47,18 +47,35 @@ static bool is_zeroed(void *from, size_t size)
 static int test_check_nonzero_user(char *kmem, char __user *umem, size_t size)
 {
        int ret = 0;
-       size_t start, end, i;
-       size_t zero_start = size / 4;
-       size_t zero_end = size - zero_start;
+       size_t start, end, i, zero_start, zero_end;
+
+       if (test(size < 2 * PAGE_SIZE, "buffer too small"))
+               return -EINVAL;
+
+       /*
+        * We want to cross a page boundary to exercise the code more
+        * effectively. We also don't want to make the size we scan too large,
+        * otherwise the test can take a long time and cause soft lockups. So
+        * scan a 1024 byte region across the page boundary.
+        */
+       size = 1024;
+       start = PAGE_SIZE - (size / 2);
+
+       kmem += start;
+       umem += start;
+
+       zero_start = size / 4;
+       zero_end = size - zero_start;
 
        /*
-        * We conduct a series of check_nonzero_user() tests on a block of memory
-        * with the following byte-pattern (trying every possible [start,end]
-        * pair):
+        * We conduct a series of check_nonzero_user() tests on a block of
+        * memory with the following byte-pattern (trying every possible
+        * [start,end] pair):
         *
         *   [ 00 ff 00 ff ... 00 00 00 00 ... ff 00 ff 00 ]
         *
-        * And we verify that check_nonzero_user() acts identically to memchr_inv().
+        * And we verify that check_nonzero_user() acts identically to
+        * memchr_inv().
         */
 
        memset(kmem, 0x0, size);
@@ -93,11 +110,13 @@ static int test_copy_struct_from_user(char *kmem, char __user *umem,
        size_t ksize, usize;
 
        umem_src = kmalloc(size, GFP_KERNEL);
-       if ((ret |= test(umem_src == NULL, "kmalloc failed")))
+       ret = test(umem_src == NULL, "kmalloc failed");
+       if (ret)
                goto out_free;
 
        expected = kmalloc(size, GFP_KERNEL);
-       if ((ret |= test(expected == NULL, "kmalloc failed")))
+       ret = test(expected == NULL, "kmalloc failed");
+       if (ret)
                goto out_free;
 
        /* Fill umem with a fixed byte pattern. */