With the following patch, the BPF_SOCK_OPS_GEN_SYNCOOKIE_CB program
can utilise the TCP Timestamps option as another storage to encode
client information.
Then, we use bpf_sock_ops.replylong[1] as the user interface to pass
the timestamp value.
Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
---
net/core/filter.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/core/filter.c b/net/core/filter.c
index cc2e4babc85f..276abecf5d90 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -9079,7 +9079,7 @@ static bool sock_ops_is_valid_access(int off, int size,
if (type == BPF_WRITE) {
switch (off) {
- case offsetof(struct bpf_sock_ops, reply):
+ case bpf_ctx_range_till(struct bpf_sock_ops, reply, replylong[1]):
case offsetof(struct bpf_sock_ops, sk_txhash):
if (size != size_default)
return false;
--
2.30.2
