livepatch/sample: Use the right type for the leaking data pointer

The "leak" pointer, in the sample of shadow variable API, is allocated as sizeof(int). Let's help developers and static analyzers with understanding the code by using the appropriate pointer type. Reported-by: Dan Carpenter <[email protected]> Signed-off-by: Petr Mladek <[email protected]> Reviewed-by: Joe Lawrence <[email protected]> Acked-by: Miroslav Benes <[email protected]> Reviewed-by: Kamalesh Babulal <[email protected]> Signed-off-by: Jiri Kosina <[email protected]>
vieko · Jan 17, 2020 · 8f6b886 · 8f6b886
1 parent f838767
commit 8f6b886
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Showing 3 changed files with 10 additions and 10 deletions.
diff --git a/samples/livepatch/livepatch-shadow-fix1.c b/samples/livepatch/livepatch-shadow-fix1.c
@@ -52,8 +52,8 @@ struct dummy {
  */
 static int shadow_leak_ctor(void *obj, void *shadow_data, void *ctor_data)
 {
-	void **shadow_leak = shadow_data;
-	void *leak = ctor_data;
+	int **shadow_leak = shadow_data;
+	int *leak = ctor_data;
 
 	*shadow_leak = leak;
 	return 0;
@@ -62,7 +62,7 @@ static int shadow_leak_ctor(void *obj, void *shadow_data, void *ctor_data)
 static struct dummy *livepatch_fix1_dummy_alloc(void)
 {
 	struct dummy *d;
-	void *leak;
+	int *leak;
 
 	d = kzalloc(sizeof(*d), GFP_KERNEL);
 	if (!d)
@@ -76,7 +76,7 @@ static struct dummy *livepatch_fix1_dummy_alloc(void)
 	 * variable.  A patched dummy_free routine can later fetch this
 	 * pointer to handle resource release.
 	 */
-	leak = kzalloc(sizeof(int), GFP_KERNEL);
+	leak = kzalloc(sizeof(*leak), GFP_KERNEL);
 	if (!leak) {
 		kfree(d);
 		return NULL;
@@ -94,7 +94,7 @@ static struct dummy *livepatch_fix1_dummy_alloc(void)
 static void livepatch_fix1_dummy_leak_dtor(void *obj, void *shadow_data)
 {
 	void *d = obj;
-	void **shadow_leak = shadow_data;
+	int **shadow_leak = shadow_data;
 
 	kfree(*shadow_leak);
 	pr_info("%s: dummy @ %p, prevented leak @ %p\n",
@@ -103,7 +103,7 @@ static void livepatch_fix1_dummy_leak_dtor(void *obj, void *shadow_data)
 
 static void livepatch_fix1_dummy_free(struct dummy *d)
 {
-	void **shadow_leak;
+	int **shadow_leak;
 
 	/*
 	 * Patch: fetch the saved SV_LEAK shadow variable, detach and

diff --git a/samples/livepatch/livepatch-shadow-fix2.c b/samples/livepatch/livepatch-shadow-fix2.c
@@ -59,7 +59,7 @@ static bool livepatch_fix2_dummy_check(struct dummy *d, unsigned long jiffies)
 static void livepatch_fix2_dummy_leak_dtor(void *obj, void *shadow_data)
 {
 	void *d = obj;
-	void **shadow_leak = shadow_data;
+	int **shadow_leak = shadow_data;
 
 	kfree(*shadow_leak);
 	pr_info("%s: dummy @ %p, prevented leak @ %p\n",
@@ -68,7 +68,7 @@ static void livepatch_fix2_dummy_leak_dtor(void *obj, void *shadow_data)
 
 static void livepatch_fix2_dummy_free(struct dummy *d)
 {
-	void **shadow_leak;
+	int **shadow_leak;
 	int *shadow_count;
 
 	/* Patch: copy the memory leak patch from the fix1 module. */

diff --git a/samples/livepatch/livepatch-shadow-mod.c b/samples/livepatch/livepatch-shadow-mod.c
@@ -95,7 +95,7 @@ struct dummy {
 static __used noinline struct dummy *dummy_alloc(void)
 {
 	struct dummy *d;
-	void *leak;
+	int *leak;
 
 	d = kzalloc(sizeof(*d), GFP_KERNEL);
 	if (!d)
@@ -105,7 +105,7 @@ static __used noinline struct dummy *dummy_alloc(void)
 		msecs_to_jiffies(1000 * EXPIRE_PERIOD);
 
 	/* Oops, forgot to save leak! */
-	leak = kzalloc(sizeof(int), GFP_KERNEL);
+	leak = kzalloc(sizeof(*leak), GFP_KERNEL);
 	if (!leak) {
 		kfree(d);
 		return NULL;