From 6b41d4d9cb8f48363e50990e00c64c3fde355d11 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Tue, 15 Jan 2019 13:41:53 -0600 Subject: libceph: use struct_size() for kmalloc() in crush_decode() 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; struct boo entry[]; }; instance = kmalloc(sizeof(struct foo) + count * sizeof(struct boo), 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 Reviewed-by: Ilya Dryomov Signed-off-by: Ilya Dryomov --- net/ceph/osdmap.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'net') diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c index 98c0ff3d6441..48a31dc9161c 100644 --- a/net/ceph/osdmap.c +++ b/net/ceph/osdmap.c @@ -495,9 +495,8 @@ static struct crush_map *crush_decode(void *pbyval, void *end) / sizeof(struct crush_rule_step)) goto bad; #endif - r = c->rules[i] = kmalloc(sizeof(*r) + - yes*sizeof(struct crush_rule_step), - GFP_NOFS); + r = kmalloc(struct_size(r, steps, yes), GFP_NOFS); + c->rules[i] = r; if (r == NULL) goto badmem; dout(" rule %d is at %p\n", i, r); -- cgit v1.2.3-59-g8ed1b