net: dsa: sja1105: Fix memory leak on meta state machine error path

When RX timestamping is enabled and two link-local (non-meta) frames are
received in a row, this constitutes an error.

The tagger is always caching the last link-local frame, in an attempt to
merge it with the meta follow-up frame when that arrives. To recover
from the above error condition, the initial cached link-local frame is
dropped and the second frame in a row is cached (in expectance of the
second meta frame).

However, when dropping the initial link-local frame, its backing memory
was being leaked.

Fixes: f3097be21bf1 ("net: dsa: sja1105: Add a state machine for RX timestamping")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
index 8fa8dda8a15b69f04e2e6503bece0e8ad809616d..47ee88163a9daede6494af72025d2f86974d167b 100644 (file)
--- a/net/dsa/tag_sja1105.c
+++ b/net/dsa/tag_sja1105.c
@@ -165,6 +165,7 @@ static struct sk_buff
                                            "Expected meta frame, is %12llx "
                                            "in the DSA master multicast filter?\n",
                                            SJA1105_META_DMAC);
+                       kfree_skb(sp->data->stampable_skb);
                }
 
                /* Hold a reference to avoid dsa_switch_rcv