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

BugLink: https://bugs.launchpad.net/bugs/1862429
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>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/net/core/filter.c b/net/core/filter.c
index 46d713d8c2ad6e6cc2c9095cb62f44ef7c1f3fec..18296f8cdacedf63b0cd8eb17f60e8ff9d9704a6 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);
        }