bpf: Use kmemdup() to replace kmalloc + memcpy

Eliminate the follow coccicheck warning:

./kernel/bpf/btf.c:6537:13-20: WARNING opportunity for kmemdup.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1639030882-92383-1-git-send-email-jiapeng.chong@linux.alibaba.com

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 8b00c6e..baa90f3 100644 (file)
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -6534,12 +6534,11 @@ static struct bpf_cand_cache *populate_cand_cache(struct bpf_cand_cache *cands,
                bpf_free_cands_from_cache(*cc);
                *cc = NULL;
        }
-       new_cands = kmalloc(sizeof_cands(cands->cnt), GFP_KERNEL);
+       new_cands = kmemdup(cands, sizeof_cands(cands->cnt), GFP_KERNEL);
        if (!new_cands) {
                bpf_free_cands(cands);
                return ERR_PTR(-ENOMEM);
        }
-       memcpy(new_cands, cands, sizeof_cands(cands->cnt));
        /* strdup the name, since it will stay in cache.
         * the cands->name points to strings in prog's BTF and the prog can be unloaded.
         */