6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jiri Olsa <jolsa@xxxxxxxxxx>
[ Upstream commit 17c4b65a24938c6dd79496cce5df15f70d9c253c ]
The kprobe session program can return only 0 or 1,
instruct verifier to check for that.
Fixes: 535a3692ba72 ("bpf: Add support for kprobe session attach")
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Link: https://lore.kernel.org/bpf/20241108134544.480660-2-jolsa@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
kernel/bpf/verifier.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 71a1877aac687..91317857ea3ee 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -15988,6 +15988,15 @@ static int check_return_code(struct bpf_verifier_env *env, int regno, const char
return -ENOTSUPP;
}
break;
+ case BPF_PROG_TYPE_KPROBE:
+ switch (env->prog->expected_attach_type) {
+ case BPF_TRACE_KPROBE_SESSION:
+ range = retval_range(0, 1);
+ break;
+ default:
+ return 0;
+ }
+ break;
case BPF_PROG_TYPE_SK_LOOKUP:
range = retval_range(SK_DROP, SK_PASS);
break;
--
2.43.0
