From ec54d7d6e40b04c16dfce0e41e506198a20c8645 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Sat, 31 Jan 2009 00:52:57 -0800 Subject: [PATCH] igb: prevent skb_over panic w/ mtu smaller than 1K A panic has been observed with frame sizes smaller than 1K. This has been root caused to the hardware spanning larger frames across multiple buffers and then reporting the original frame size in the first descriptor. To prevent this we can enable set the LPE bit which in turn will restrict packet sizes to those set in the RLPML register. Signed-off-by: Alexander Duyck Signed-off-by: Jeff Kirsher Signed-off-by: David S. Miller --- drivers/net/igb/igb_main.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c index cc94412ddf8..a50db5398fa 100644 --- a/drivers/net/igb/igb_main.c +++ b/drivers/net/igb/igb_main.c @@ -1834,11 +1834,11 @@ static void igb_setup_rctl(struct igb_adapter *adapter) rctl |= E1000_RCTL_SECRC; /* - * disable store bad packets, long packet enable, and clear size bits. + * disable store bad packets and clear size bits. */ - rctl &= ~(E1000_RCTL_SBP | E1000_RCTL_LPE | E1000_RCTL_SZ_256); + rctl &= ~(E1000_RCTL_SBP | E1000_RCTL_SZ_256); - if (adapter->netdev->mtu > ETH_DATA_LEN) + /* enable LPE when to prevent packets larger than max_frame_size */ rctl |= E1000_RCTL_LPE; /* Setup buffer sizes */ @@ -1864,7 +1864,7 @@ static void igb_setup_rctl(struct igb_adapter *adapter) */ /* allocations using alloc_page take too long for regular MTU * so only enable packet split for jumbo frames */ - if (rctl & E1000_RCTL_LPE) { + if (adapter->netdev->mtu > ETH_DATA_LEN) { adapter->rx_ps_hdr_size = IGB_RXBUFFER_128; srrctl |= adapter->rx_ps_hdr_size << E1000_SRRCTL_BSIZEHDRSIZE_SHIFT; -- 2.41.1