fix skb binding time in some network drivers due to skb_padto conversion
PATCH 1/1 fix skb binding time in some network drivers due to skb_padto conversion
Hi,
It seems that skb_padto security fixes in 2.4 and 2.5 trying to fix "CAN-2003-0001:Multiple ethernet NID device drivers do not pad frames with null bytes", do not put the skb_padto blocks in proper places in the 3c527, eth16i, fmv18x, seeq8005, yellowfin device drivers.
In case a driver calls skb_padto(), it is possible
that the space available in the original skb buffer tailroom is less than the space to pad. In this case, in short, the skb_padto() will create a new skb buffer, copy data from the original skb buffer to a new skb buffer, free the original buffer, and finally return the new buffer.
If this happens to the aforementioned device drivers, they come to point to wrong data. And, for 3c527 and yellowfin, the drivers can unexpectedly double free the original skb buffers since they still point to the original skb buffers. The attached patch against 2.4.23pre1 fixes these issues.
If the patch looks okay, please consider including it in 2.4 and 2.5/6.
Regards,
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drivers/net/3c527.c Sat Aug 30 00:44:47 2003 renamed from drivers/net/3c527.c Fri Aug 29 04:00:19 2003 +4 -3
@@ -1083,15 +1083,16 @@ /* NP is the buffer we will be loading */ np=lp->tx_ring[lp->tx_ring_head].p; - /* We will need this to flush the buffer out */ - lp->tx_ring[lp->tx_ring_head].skb=skb; - if(skb->len < ETH_ZLEN) { skb = skb_padto(skb, ETH_ZLEN); if(skb == NULL) goto out; } + + /* We will need this to flush the buffer out */ + lp->tx_ring[lp->tx_ring_head].skb=skb; + np->length = (skb->len < ETH_ZLEN) ? ETH_ZLEN : skb->len; np->data = virt_to_bus(skb->data);
drivers/net/eth16i.c Sat Aug 30 00:10:33 2003 renamed from drivers/net/eth16i.c Tue Feb 4 04:00:34 2003 +2 -1
@@ -1057,7 +1057,7 @@ int ioaddr = dev->base_addr; int status = 0; ushort length = skb->len; - unsigned char *buf = skb->data; + unsigned char *buf; unsigned long flags; if(length < ETH_ZLEN)
@@ -1067,6 +1067,7 @@ return 0; length = ETH_ZLEN; } + buf = skb->data; netif_stop_queue(dev);
drivers/net/fmv18x.c Sat Aug 30 00:12:06 2003 renamed from drivers/net/fmv18x.c Tue Feb 4 04:00:34 2003 +2 -1
@@ -370,7 +370,7 @@ struct net_local *lp = dev->priv; int ioaddr = dev->base_addr; short length = skb->len; - unsigned char *buf = skb->data; + unsigned char *buf; unsigned long flags; /* Block a transmit from overlapping. */
@@ -389,6 +389,7 @@ return 0; length = ETH_ZLEN; } + buf = skb->data; if (net_debug > 4) printk("%s: Transmitting a packet of length %lu.\n", dev->name,
drivers/net/seeq8005.c Sat Aug 30 00:13:27 2003 renamed from drivers/net/seeq8005.c Tue Feb 4 04:00:34 2003 +3 -1
@@ -379,7 +379,7 @@ { struct net_local *lp = (struct net_local *)dev->priv; short length = skb->len; - unsigned char *buf = skb->data; + unsigned char *buf; if(length < ETH_ZLEN) {
@@ -388,6 +388,8 @@ return 0; length = ETH_ZLEN; } + buf = skb->data; + /* Block a timer-based transmit from overlapping */ netif_stop_queue(dev);
drivers/net/yellowfin.c Sat Aug 30 00:26:57 2003 renamed from drivers/net/yellowfin.c Tue Feb 4 04:00:34 2003 +2 -2
@@ -867,8 +867,6 @@ /* Calculate the next Tx descriptor entry. */ entry = yp->cur_tx % TX_RING_SIZE; - yp->tx_skbuff[entry] = skb; - if (gx_fix) { /* Note: only works for paddable protocols e.g. IP. */ int cacheline_end = ((unsigned long)skb->data + skb->len) % 32; /* Fix GX chipset errata. */
@@ -885,6 +883,8 @@ return 0; } } + yp->tx_skbuff[entry] = skb; + #ifdef NO_TXSTATS yp->tx_ring[entry].addr = cpu_to_le32(pci_map_single(yp->pci_dev, skb->data, len, PCI_DMA_TODEVICE));