[PATCH 1/4] devres: Provide krealloc_array

[James Clark <james.clark@arm.com>]

There is no krealloc_array equivalent in devres. Users would have to
do their own multiplication overflow check so provide one.

Signed-off-by: James Clark <james.clark@arm.com>
---
 Documentation/driver-api/driver-model/devres.rst |  1 +
 include/linux/device.h                           | 10 ++++++++++
 2 files changed, 11 insertions(+)

diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index 4249eb4239e0..8be086b3f829 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -364,6 +364,7 @@ MEM
   devm_kmalloc_array()
   devm_kmemdup()
   devm_krealloc()
+  devm_krealloc_array()
   devm_kstrdup()
   devm_kstrdup_const()
   devm_kvasprintf()
diff --git a/include/linux/device.h b/include/linux/device.h
index 1508e637bb26..0dd5956c8516 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -223,6 +223,16 @@ static inline void *devm_kcalloc(struct device *dev,
 {
 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
 }
+static inline __realloc_size(3, 4) void * __must_check
+devm_krealloc_array(struct device *dev, void *p, size_t new_n, size_t new_size, gfp_t flags)
+{
+	size_t bytes;
+
+	if (unlikely(check_mul_overflow(new_n, new_size, &bytes)))
+		return NULL;
+	return devm_krealloc(dev, p, bytes, flags);
+}
+
 void devm_kfree(struct device *dev, const void *p);
 char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
 const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp);
-- 
2.34.1