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

commit cf21e9ba1eb86c9333ca5b05b2f1cc94021bcaef upstream.

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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/core/filter.c b/net/core/filter.c
index 9eeef8a8ab6d4125e2785fe5fd56eee31ef1ba66..a0b68cbda7bc9e9e3a225304085b63ce2e69e676 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);
        }