Re: [patch linux-2.6.11-bk10 1/1] r8169: incoming frame length check
From: Jon Mason <hidden>
Date: 2005-03-16 20:30:17
On Monday 14 March 2005 05:31 pm, Francois Romieu wrote:
The size of the incoming frame is not correctly checked. The RxMaxSize register (0xDA) does not work as expected and incoming frames whose size exceeds the MTU actually end spanning multiple descriptors. The first Rx descriptor contains the size of the whole frame (or some garbage in its place). The driver does not expect something above the space allocated to the current skb and crashes loudly when it issues a skb_put. The fix contains two parts: - disable hardware Rx size filtering: so far it only proved to be able to trigger some new fancy errors; - drop multi-descriptors frame: as the driver allocates MTU sized Rx buffers, it provides an adequate filtering. As a bonus, wrong descriptors were not returned to the asic after their processing. Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Applies cleanly and lightly tested on amd64 (kernel version 2.6.11.3).
quoted hunk ↗ jump to hunk
diff -puN drivers/net/r8169.c~r8169-570 drivers/net/r8169.c--- linux-2.6.11/drivers/net/r8169.c~r8169-570 2005-03-1323:35:37.000000000 +0100 +++ linux-2.6.11-fr/drivers/net/r8169.c 2005-03-14 23:47:56.529014957 +0100 @@ -1585,8 +1585,8 @@ rtl8169_hw_start(struct net_device *dev) RTL_W8(ChipCmd, CmdTxEnb | CmdRxEnb); RTL_W8(EarlyTxThres, EarlyTxThld); - /* For gigabit rtl8169, MTU + header + CRC + VLAN */ - RTL_W16(RxMaxSize, tp->rx_buf_sz); + /* Low hurts. Let's disable the filtering. */ + RTL_W16(RxMaxSize, 16383);
Wouldn't a #define be better than 16k-1? Perhaps, RxPacketMaxSize could be used.
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/* Set Rx Config register */ i = rtl8169_rx_config |@@ -2127,6 +2127,11 @@ rtl8169_tx_interrupt(struct net_device * } } +static inline int rtl8169_fragmented_frame(u32 status) +{ + return (status & (FirstFrag | LastFrag)) != (FirstFrag | LastFrag); +} + static inline void rtl8169_rx_csum(struct sk_buff *skb, struct RxDesc*desc) { u32 opts1 = le32_to_cpu(desc->opts1);@@ -2177,27 +2182,41 @@ rtl8169_rx_interrupt(struct net_device * while (rx_left > 0) { unsigned int entry = cur_rx % NUM_RX_DESC; + struct RxDesc *desc = tp->RxDescArray + entry; u32 status; rmb(); - status = le32_to_cpu(tp->RxDescArray[entry].opts1); + status = le32_to_cpu(desc->opts1); if (status & DescOwn) break; if (status & RxRES) { - printk(KERN_INFO "%s: Rx ERROR!!!\n", dev->name); + printk(KERN_INFO "%s: Rx ERROR. status = %08x\n", + dev->name, status); tp->stats.rx_errors++; if (status & (RxRWT | RxRUNT)) tp->stats.rx_length_errors++; if (status & RxCRC) tp->stats.rx_crc_errors++; + rtl8169_mark_to_asic(desc, tp->rx_buf_sz); } else { - struct RxDesc *desc = tp->RxDescArray + entry; struct sk_buff *skb = tp->Rx_skbuff[entry]; int pkt_size = (status & 0x00001FFF) - 4; void (*pci_action)(struct pci_dev *, dma_addr_t, size_t, int) = pci_dma_sync_single_for_device; + /* + * The driver does not support incoming fragmented + * frames. They are seen as a symptom of over-mtu + * sized frames. + */ + if (unlikely(rtl8169_fragmented_frame(status))) { + tp->stats.rx_dropped++; + tp->stats.rx_length_errors++; + rtl8169_mark_to_asic(desc, tp->rx_buf_sz); + goto move_on; + } + rtl8169_rx_csum(skb, desc); pci_dma_sync_single_for_cpu(tp->pci_dev,@@ -2224,7 +2243,7 @@ rtl8169_rx_interrupt(struct net_device * tp->stats.rx_bytes += pkt_size; tp->stats.rx_packets++; } - +move_on: cur_rx++; rx_left--; }_
Looks similar to some of the > 8k Jumbo Frames changes. Should make the diff for next patch much cleaner. Thanks. -- Jon Mason jdmason@us.ibm.com