Currently the multi_kprobe link attach does not check error
injection list for programs with bpf_override_return helper
and allows them to attach anywhere. Adding the missing check.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 0dcac2725406 ("bpf: Add multi kprobe link")
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
kernel/trace/bpf_trace.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index a7264b2c17ad..c1c1af63ced2 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -2853,6 +2853,17 @@ static int get_modules_for_addrs(struct module ***mods, unsigned long *addrs, u3
return arr.mods_cnt;
}
+static int addrs_check_error_injection_list(unsigned long *addrs, u32 cnt)
+{
+ u32 i;
+
+ for (i = 0; i < cnt; i++) {
+ if (!within_error_injection_list(addrs[i]))
+ return -EINVAL;
+ }
+ return 0;
+}
+
int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
{
struct bpf_kprobe_multi_link *link = NULL;
@@ -2930,6 +2941,11 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
goto error;
}
+ if (prog->kprobe_override && addrs_check_error_injection_list(addrs, cnt)) {
+ err = -EINVAL;
+ goto error;
+ }
+
link = kzalloc(sizeof(*link), GFP_KERNEL);
if (!link) {
err = -ENOMEM;
--
2.41.0
