Merge tag 'v5.9-rc2' into regulator-5.9

Linux 5.9-rc2

1 files changed, 18 insertions, 7 deletions

diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index 0bbb328bd17f..ed615d3b9cf1 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -89,15 +89,23 @@ static struct devres_group * node_to_group(struct devres_node *node)
 	return NULL;
 }
 
+static bool check_dr_size(size_t size, size_t *tot_size)
+{
+	/* We must catch any near-SIZE_MAX cases that could overflow. */
+	if (unlikely(check_add_overflow(sizeof(struct devres),
+					size, tot_size)))
+		return false;
+
+	return true;
+}
+
 static __always_inline struct devres * alloc_dr(dr_release_t release,
 						size_t size, gfp_t gfp, int nid)
 {
 	size_t tot_size;
 	struct devres *dr;
 
-	/* We must catch any near-SIZE_MAX cases that could overflow. */
-	if (unlikely(check_add_overflow(sizeof(struct devres), size,
-					&tot_size)))
+	if (!check_dr_size(size, &tot_size))
 		return NULL;
 
 	dr = kmalloc_node_track_caller(tot_size, gfp, nid);
@@ -807,10 +815,13 @@ static int devm_kmalloc_match(struct device *dev, void *res, void *data)
  * RETURNS:
  * Pointer to allocated memory on success, NULL on failure.
  */
-void * devm_kmalloc(struct device *dev, size_t size, gfp_t gfp)
+void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp)
 {
 	struct devres *dr;
 
+	if (unlikely(!size))
+		return ZERO_SIZE_PTR;
+
 	/* use raw alloc_dr for kmalloc caller tracing */
 	dr = alloc_dr(devm_kmalloc_release, size, gfp, dev_to_node(dev));
 	if (unlikely(!dr))
@@ -942,10 +953,10 @@ void devm_kfree(struct device *dev, const void *p)
 	int rc;
 
 	/*
-	 * Special case: pointer to a string in .rodata returned by
-	 * devm_kstrdup_const().
+	 * Special cases: pointer to a string in .rodata returned by
+	 * devm_kstrdup_const() or NULL/ZERO ptr.
 	 */
-	if (unlikely(is_kernel_rodata((unsigned long)p)))
+	if (unlikely(is_kernel_rodata((unsigned long)p) || ZERO_OR_NULL_PTR(p)))
 		return;
 
 	rc = devres_destroy(dev, devm_kmalloc_release,