Commit 864c17c3 authored Oct 18, 2017 by Julian Wiedmann Committed by David S. Miller Oct 20, 2017

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>

parent 8d68af6a

drivers/s390/net/qeth_core_main.c

+1 −3

Original line number	Diff line number	Diff line
		@@ -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;