From e736bf72af568d0a04f186e1c5dde6789b19c35e Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Wed, 5 Jun 2019 09:45:16 -0500 Subject: [PATCH] lib: objagg: Use struct_size() in kzalloc() 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 objagg_stats { ... struct objagg_obj_stats_info stats_info[]; }; size = sizeof(*objagg_stats) + sizeof(objagg_stats->stats_info[0]) * count; instance = kzalloc(size, 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, stats_info, count), GFP_KERNEL); Notice that, in this case, variable alloc_size is not necessary, hence it is removed. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva Acked-by: Jiri Pirko Signed-off-by: David S. Miller --- lib/objagg.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/lib/objagg.c b/lib/objagg.c index 576be22e86de..55621fb82e0a 100644 --- a/lib/objagg.c +++ b/lib/objagg.c @@ -605,12 +605,10 @@ const struct objagg_stats *objagg_stats_get(struct objagg *objagg) { struct objagg_stats *objagg_stats; struct objagg_obj *objagg_obj; - size_t alloc_size; int i; - alloc_size = sizeof(*objagg_stats) + - sizeof(objagg_stats->stats_info[0]) * objagg->obj_count; - objagg_stats = kzalloc(alloc_size, GFP_KERNEL); + objagg_stats = kzalloc(struct_size(objagg_stats, stats_info, + objagg->obj_count), GFP_KERNEL); if (!objagg_stats) return ERR_PTR(-ENOMEM);