6.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eduard Zingerman eddyz87@gmail.com
[ Upstream commit 1479eaff1f16983d8fda7c5a08a586c21891087d ]
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 jemarch@gnu.org Signed-off-by: Eduard Zingerman eddyz87@gmail.com Link: https://lore.kernel.org/r/20240424012821.595216-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 de33dc1b0daad..fdbe30ad8db2f 100644 --- a/net/bpf/bpf_dummy_struct_ops.c +++ b/net/bpf/bpf_dummy_struct_ops.c @@ -230,7 +230,7 @@ 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; } @@ -247,7 +247,7 @@ 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, };