bpf: Sockmap/tls, msg_push_data may leave end mark in place

Leaving an incorrect end mark in place when passing to crypto
layer will cause crypto layer to stop processing data before
all data is encrypted. To fix clear the end mark on push
data instead of expecting users of the helper to clear the
mark value after the fact.

This happens when we push data into the middle of a skmsg and
have room for it so we don't do a set of copies that already
clear the end flag.

Fixes: 6fff607e2f14b ("bpf: sk_msg program helper bpf_msg_push_data")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/bpf/20200111061206.8028-6-john.fastabend@gmail.com

diff --git a/net/core/filter.c b/net/core/filter.c
index ffa2278020d766da6b9693908e6f8d72b4ddce3d..538f6a735a19f017df8e10149cb578107ddc8cbb 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -2415,6 +2415,7 @@ BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start,
 
                sk_msg_iter_var_next(i);
                sg_unmark_end(psge);
+               sg_unmark_end(&rsge);
                sk_msg_iter_next(msg, end);
        }