net/tls: free the record on encryption error

When tls_do_encryption() fails the SG lists are left with the
SG_END and SG_CHAIN marks in place. One could hope that once
encryption fails we will never see the record again, but that
is in fact not true. Commit d3b18ad31f93 ("tls: add bpf support
to sk_msg handling") added special handling to ENOMEM and ENOSPC
errors which mean we may see the same record re-submitted.

As suggested by John free the record, the BPF code is already
doing just that.

Reported-by: syzbot+df0d4ec12332661dd1f9@syzkaller.appspotmail.com
Fixes: d3b18ad31f93 ("tls: add bpf support to sk_msg handling")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 70e3c0c1af50cec2c91696f14bf095768e862eb0..dbba51b69d212b449ec398aa2cdd26aa221ceb05 100644 (file)
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -771,8 +771,14 @@ static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk,
 
        policy = !(flags & MSG_SENDPAGE_NOPOLICY);
        psock = sk_psock_get(sk);
-       if (!psock || !policy)
-               return tls_push_record(sk, flags, record_type);
+       if (!psock || !policy) {
+               err = tls_push_record(sk, flags, record_type);
+               if (err) {
+                       *copied -= sk_msg_free(sk, msg);
+                       tls_free_open_rec(sk);
+               }
+               return err;
+       }
 more_data:
        enospc = sk_msg_full(msg);
        if (psock->eval == __SK_NONE) {