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net: mvneta: fix refilling for Rx DMA buffers

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With the actual code, if a memory allocation error happens while
refilling a Rx descriptor, then the original Rx buffer is both passed
to the networking stack (in a SKB) and let in the Rx ring. This leads
to various kernel oops and crashes.

As a fix, this patch moves Rx descriptor refilling ahead of building
SKB with the associated Rx buffer. In case of a memory allocation
failure, data is dropped and the original DMA buffer is put back into
the Rx ring.

Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Fixes: c5aff18204 ("net: mvneta: driver for Marvell Armada 370/XP network unit")
Cc: <stable@vger.kernel.org> # v3.8+
Tested-by: Yoann Sculo <yoann@sculo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Simon Guinot 2015-07-19 13:00:53 +02:00 committed by David S. Miller
parent a7a6268590
commit a84e328941
1 changed files with 10 additions and 12 deletions
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22
drivers/net/ethernet/marvell/mvneta.c
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@ -1462,7 +1462,7 @@ static int mvneta_rx(struct mvneta_port *pp, int rx_todo,
struct mvneta_rx_queue *rxq)
{
struct net_device *dev = pp->dev;
int rx_done, rx_filled;
int rx_done;
u32 rcvd_pkts = 0;
u32 rcvd_bytes = 0;
@ -1473,7 +1473,6 @@ static int mvneta_rx(struct mvneta_port *pp, int rx_todo,
rx_todo = rx_done;
rx_done = 0;
rx_filled = 0;
/* Fairness NAPI loop */
while (rx_done < rx_todo) {
@ -1484,7 +1483,6 @@ static int mvneta_rx(struct mvneta_port *pp, int rx_todo,
int rx_bytes, err;
rx_done++;
rx_filled++;
rx_status = rx_desc->status;
rx_bytes = rx_desc->data_size - (ETH_FCS_LEN + MVNETA_MH_SIZE);
data = (unsigned char *)rx_desc->buf_cookie;
@ -1524,6 +1522,14 @@ static int mvneta_rx(struct mvneta_port *pp, int rx_todo,
continue;
}
/* Refill processing */
err = mvneta_rx_refill(pp, rx_desc);
if (err) {
netdev_err(dev, "Linux processing - Can't refill\n");
rxq->missed++;
goto err_drop_frame;
}
skb = build_skb(data, pp->frag_size > PAGE_SIZE ? 0 : pp->frag_size);
if (!skb)
goto err_drop_frame;
@ -1543,14 +1549,6 @@ static int mvneta_rx(struct mvneta_port *pp, int rx_todo,
mvneta_rx_csum(pp, rx_status, skb);
napi_gro_receive(&pp->napi, skb);
/* Refill processing */
err = mvneta_rx_refill(pp, rx_desc);
if (err) {
netdev_err(dev, "Linux processing - Can't refill\n");
rxq->missed++;
rx_filled--;
}
}
if (rcvd_pkts) {
@ -1563,7 +1561,7 @@ static int mvneta_rx(struct mvneta_port *pp, int rx_todo,
}
/* Update rxq management counters */
mvneta_rxq_desc_num_update(pp, rxq, rx_done, rx_filled);
mvneta_rxq_desc_num_update(pp, rxq, rx_done, rx_done);
return rx_done;
}