Re: [PATCH net-next] xprtrdma: Use struct_size() in kzalloc()
From: Chuck Lever <chuck.lever@oracle.com>
Date: 2019-01-31 14:11:54
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On Jan 30, 2019, at 7:46 PM, Gustavo A. R. Silva [off-list ref] wrote:
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 = kzalloc(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 = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <redacted>Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
quoted hunk ↗ jump to hunk
--- net/sunrpc/xprtrdma/verbs.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 4994e75945b8..9e8cf7456840 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c@@ -811,8 +811,7 @@ static struct rpcrdma_sendctx *rpcrdma_sendctx_create(struct rpcrdma_ia *ia){ struct rpcrdma_sendctx *sc; - sc = kzalloc(sizeof(*sc) + - ia->ri_max_send_sges * sizeof(struct ib_sge), + sc = kzalloc(struct_size(sc, sc_sges, ia->ri_max_send_sges), GFP_KERNEL); if (!sc) return NULL; -- 2.20.1
-- Chuck Lever