s390/qeth: try harder to get packets from RX buffer

Current code bails out when two subsequent buffer elements hold
insufficient data to contain a qeth_hdr packet descriptor.
This seems reasonable, but it would be legal for quirky hardware to
leave a few elements empty and then present packets in a subsequent
element. These packets would currently be dropped.

So make sure to check all buffer elements, until we hit the LAST_ENTRY
indication.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 23b439f..8855bc8 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -5214,13 +5214,11 @@ struct sk_buff *qeth_core_get_next_skb(struct qeth_card *card,
        int use_rx_sg = 0;
 
        /* qeth_hdr must not cross element boundaries */
-       if (element->length < offset + sizeof(struct qeth_hdr)) {
+       while (element->length < offset + sizeof(struct qeth_hdr)) {
                if (qeth_is_last_sbale(element))
                        return NULL;
                element++;
                offset = 0;
-               if (element->length < sizeof(struct qeth_hdr))
-                       return NULL;
        }
        *hdr = element->addr + offset;