md/raid10: Use struct_size() in kmalloc()
PATCH 1/1 md/raid10: Use struct_size() in kmalloc()
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.
--- drivers/md/raid10.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
drivers/md/raid10.c +1 -2
@@ -4788,8 +4788,7 @@ static int handle_reshape_read_error(struct mddev *mddev,int idx =0 ;struct page **pages; - r10b =kmalloc (sizeof (*r10b) + -sizeof (struct r10dev ) * conf->copies,GFP_NOIO ); + r10b =kmalloc (struct_size (r10b, devs, conf->copies),GFP_NOIO );if (!r10b) {set_bit (MD_RECOVERY_INTR , &mddev->recovery);return -ENOMEM ;
Signature · 1 line
2.20.1
Quoted 12 lines · Gustavo A. R. Silva
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);
Quoted 8 lines
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 <[email protected]>
Quoted 21 lines
--- drivers/md/raid10.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)drivers/md/raid10.c +1
-3@@ -4788,8 +4788,7 @@ static int handle_reshape_read_error(struct mddev *mddev,int idx =0 ;struct page **pages; - r10b =kmalloc (sizeof (*r10b) + -sizeof (struct r10dev ) * conf->copies,GFP_NOIO ); + r10b =kmalloc (struct_size (r10b, devs, conf->copies),GFP_NOIO );if (!r10b) {set_bit (MD_RECOVERY_INTR , &mddev->recovery);return -ENOMEM ; --2.20.1