Don't allow BPF program to set flow_keys->nhoff to less than initial
value. We currently don't read the value afterwards in anything but
the tests, but it's still a good practice to return consistent
values to the test programs.
Signed-off-by: Stanislav Fomichev <s...@google.com>
---
net/core/flow_dissector.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 0dac3382e841..3b35fc35f583 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -716,7 +716,7 @@ bool bpf_flow_dissect(struct bpf_prog *prog, struct
bpf_flow_dissector *ctx,
result = BPF_PROG_RUN(prog, ctx);
- flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, 0, hlen);
+ flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen);
flow_keys->thoff = clamp_t(u16, flow_keys->thoff,
flow_keys->nhoff, hlen);
--
2.21.0.392.gf8f6787159e-goog
