[PATCH 5.4 112/222] bpf: Sockmap/tls, msg_push_data may leave end mark in place

From: Greg Kroah-Hartman
Date: Wed Jan 22 2020 - 08:23:47 EST


From: John Fastabend <john.fastabend@xxxxxxxxx>

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@xxxxxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Acked-by: Song Liu <songliubraving@xxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/bpf/20200111061206.8028-6-john.fastabend@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
net/core/filter.c | 1 +
1 file changed, 1 insertion(+)

--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -2415,6 +2415,7 @@ BPF_CALL_4(bpf_msg_push_data, struct sk_

sk_msg_iter_var_next(i);
sg_unmark_end(psge);
+ sg_unmark_end(&rsge);
sk_msg_iter_next(msg, end);
}