From a7551b75fe47fb6fb70f679935845e741c5e0855 Mon Sep 17 00:00:00 2001 From: Robert Love Date: Wed, 24 Mar 2010 10:02:04 +0000 Subject: [PATCH] ixgbe: Don't allow user buffer count to exceed 256 If the user buffer count was 256 the shift would place a 1 in the offset region leading to errors. It also overwrites the uers buffer list. This patch makes sure that at most 256 user buffers are allowed for DDP and the buffer count is masked properly such that it doesn't overwrite the offset when shifting the bits. Signed-off-by: Robert Love Signed-off-by: Yi Zou Signed-off-by: Frank Zhang Signed-off-by: Jeff Kirsher Signed-off-by: David S. Miller --- drivers/net/ixgbe/ixgbe_fcoe.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/drivers/net/ixgbe/ixgbe_fcoe.c b/drivers/net/ixgbe/ixgbe_fcoe.c index 700cfc0aa1b9..e1978da49e5b 100644 --- a/drivers/net/ixgbe/ixgbe_fcoe.c +++ b/drivers/net/ixgbe/ixgbe_fcoe.c @@ -202,6 +202,15 @@ int ixgbe_fcoe_ddp_get(struct net_device *netdev, u16 xid, addr = sg_dma_address(sg); len = sg_dma_len(sg); while (len) { + /* max number of buffers allowed in one DDP context */ + if (j >= IXGBE_BUFFCNT_MAX) { + netif_err(adapter, drv, adapter->netdev, + "xid=%x:%d,%d,%d:addr=%llx " + "not enough descriptors\n", + xid, i, j, dmacount, (u64)addr); + goto out_noddp_free; + } + /* get the offset of length of current buffer */ thisoff = addr & ((dma_addr_t)bufflen - 1); thislen = min((bufflen - thisoff), len); @@ -227,20 +236,13 @@ int ixgbe_fcoe_ddp_get(struct net_device *netdev, u16 xid, len -= thislen; addr += thislen; j++; - /* max number of buffers allowed in one DDP context */ - if (j > IXGBE_BUFFCNT_MAX) { - DPRINTK(DRV, ERR, "xid=%x:%d,%d,%d:addr=%llx " - "not enough descriptors\n", - xid, i, j, dmacount, (u64)addr); - goto out_noddp_free; - } } } /* only the last buffer may have non-full bufflen */ lastsize = thisoff + thislen; fcbuff = (IXGBE_FCBUFF_4KB << IXGBE_FCBUFF_BUFFSIZE_SHIFT); - fcbuff |= (j << IXGBE_FCBUFF_BUFFCNT_SHIFT); + fcbuff |= ((j & 0xff) << IXGBE_FCBUFF_BUFFCNT_SHIFT); fcbuff |= (firstoff << IXGBE_FCBUFF_OFFSET_SHIFT); fcbuff |= (IXGBE_FCBUFF_VALID); -- GitLab