bpf: sockmap: Enable map_update_elem from bpf_iter
Allow passing a pointer to a BTF struct sock_common* when updating
a sockmap or sockhash. Since BTF pointers can fault and therefore be
NULL at runtime we need to add an additional !sk check to
sock_map_update_elem. Since we may be passed a request or timewait
socket we also need to check sk_fullsock. Doing this allows calling
map_update_elem on sockmap from bpf_iter context, which uses
BTF pointers.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200928090805.23343-2-lmb@cloudflare.com
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index b25ba98..cc9c90d 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3943,7 +3943,7 @@ static int resolve_map_arg_type(struct bpf_verifier_env *env,
case BPF_MAP_TYPE_SOCKMAP:
case BPF_MAP_TYPE_SOCKHASH:
if (*arg_type == ARG_PTR_TO_MAP_VALUE) {
- *arg_type = ARG_PTR_TO_SOCKET;
+ *arg_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON;
} else {
verbose(env, "invalid arg_type for sockmap/sockhash\n");
return -EINVAL;
