r8169: fix crash when large packets are received
Michael Tokarev reported receiving a large packet could crash
a machine with RTL8169 NIC.
( original thread at http://lkml.org/lkml/2009/6/8/192 )
Problem is this driver tells that NIC frames up to 16383 bytes
can be received but provides skb to rx ring allocated with
smaller sizes (1536 bytes in case standard 1500 bytes MTU is used)
When a frame larger than what was allocated by driver is received,
dma transfert can occurs past the end of buffer and corrupt
kernel memory.
Fix is to tell to NIC what is the maximum size a frame can be.
This bug is very old, (before git introduction, linux-2.6.10), and
should be backported to stable versions.
Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c
index 8247a94..3b19e0c 100644
--- a/drivers/net/r8169.c
+++ b/drivers/net/r8169.c
@@ -66,7 +66,6 @@
#define RX_DMA_BURST 6 /* Maximum PCI burst, '6' is 1024 */
#define TX_DMA_BURST 6 /* Maximum PCI burst, '6' is 1024 */
#define EarlyTxThld 0x3F /* 0x3F means NO early transmit */
-#define RxPacketMaxSize 0x3FE8 /* 16K - 1 - ETH_HLEN - VLAN - CRC... */
#define SafeMtu 0x1c20 /* ... actually life sucks beyond ~7k */
#define InterFrameGap 0x03 /* 3 means InterFrameGap = the shortest one */
@@ -2357,10 +2356,10 @@
return cmd;
}
-static void rtl_set_rx_max_size(void __iomem *ioaddr)
+static void rtl_set_rx_max_size(void __iomem *ioaddr, unsigned int rx_buf_sz)
{
/* Low hurts. Let's disable the filtering. */
- RTL_W16(RxMaxSize, 16383);
+ RTL_W16(RxMaxSize, rx_buf_sz);
}
static void rtl8169_set_magic_reg(void __iomem *ioaddr, unsigned mac_version)
@@ -2407,7 +2406,7 @@
RTL_W8(EarlyTxThres, EarlyTxThld);
- rtl_set_rx_max_size(ioaddr);
+ rtl_set_rx_max_size(ioaddr, tp->rx_buf_sz);
if ((tp->mac_version == RTL_GIGA_MAC_VER_01) ||
(tp->mac_version == RTL_GIGA_MAC_VER_02) ||
@@ -2668,7 +2667,7 @@
RTL_W8(EarlyTxThres, EarlyTxThld);
- rtl_set_rx_max_size(ioaddr);
+ rtl_set_rx_max_size(ioaddr, tp->rx_buf_sz);
tp->cp_cmd |= RTL_R16(CPlusCmd) | PktCntrDisable | INTT_1;
@@ -2846,7 +2845,7 @@
RTL_W8(EarlyTxThres, EarlyTxThld);
- rtl_set_rx_max_size(ioaddr);
+ rtl_set_rx_max_size(ioaddr, tp->rx_buf_sz);
tp->cp_cmd |= rtl_rw_cpluscmd(ioaddr) | PCIMulRW;