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Subject[PATCH 1/6] afs: Use struct_size() in kzalloc()
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From: Gustavo A. R. Silva <gustavo@embeddedor.com>

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 = kzalloc(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 = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
---

fs/afs/server_list.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/fs/afs/server_list.c b/fs/afs/server_list.c
index 95d0761cdb34..155dc14caef9 100644
--- a/fs/afs/server_list.c
+++ b/fs/afs/server_list.c
@@ -42,9 +42,7 @@ struct afs_server_list *afs_alloc_server_list(struct afs_cell *cell,
if (vldb->fs_mask[i] & type_mask)
nr_servers++;

- slist = kzalloc(sizeof(struct afs_server_list) +
- sizeof(struct afs_server_entry) * nr_servers,
- GFP_KERNEL);
+ slist = kzalloc(struct_size(slist, servers, nr_servers), GFP_KERNEL);
if (!slist)
goto error;

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