One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:
struct foo {
int stuff;
void *entry[];
};
instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:
instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
---
block/bio-integrity.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 1b633a3526d4..ae8c68ecc0ca 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -57,8 +57,8 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
unsigned inline_vecs;
if (!bs || !mempool_initialized(&bs->bio_integrity_pool)) {
- bip = kmalloc(sizeof(struct bio_integrity_payload) +
- sizeof(struct bio_vec) * nr_vecs, gfp_mask);
+ bip = kmalloc(struct_size(bip, bip_inline_vecs, nr_vecs),
+ gfp_mask);
inline_vecs = nr_vecs;
} else {
bip = mempool_alloc(&bs->bio_integrity_pool, gfp_mask);
--
2.20.1
