From 1479eaff1f16983d8fda7c5a08a586c21891087d Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Tue, 23 Apr 2024 18:28:17 -0700 Subject: [PATCH] bpf: mark bpf_dummy_struct_ops.test_1 parameter as nullable Test case dummy_st_ops/dummy_init_ret_value passes NULL as the first parameter of the test_1() function. Mark this parameter as nullable to make verifier aware of such possibility. Otherwise, NULL check in the test_1() code: SEC("struct_ops/test_1") int BPF_PROG(test_1, struct bpf_dummy_ops_state *state) { if (!state) return ...; ... access state ... } Might be removed by verifier, thus triggering NULL pointer dereference under certain conditions. Reported-by: Jose E. Marchesi Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20240424012821.595216-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov --- net/bpf/bpf_dummy_struct_ops.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/bpf/bpf_dummy_struct_ops.c b/net/bpf/bpf_dummy_struct_ops.c index 25b75844891a..8f413cdfd91a 100644 --- a/net/bpf/bpf_dummy_struct_ops.c +++ b/net/bpf/bpf_dummy_struct_ops.c @@ -232,7 +232,7 @@ static void bpf_dummy_unreg(void *kdata) { } -static int bpf_dummy_test_1(struct bpf_dummy_ops_state *cb) +static int bpf_dummy_ops__test_1(struct bpf_dummy_ops_state *cb__nullable) { return 0; } @@ -249,7 +249,7 @@ static int bpf_dummy_test_sleepable(struct bpf_dummy_ops_state *cb) } static struct bpf_dummy_ops __bpf_bpf_dummy_ops = { - .test_1 = bpf_dummy_test_1, + .test_1 = bpf_dummy_ops__test_1, .test_2 = bpf_dummy_test_2, .test_sleepable = bpf_dummy_test_sleepable, };