From a0ae17a63e08a57a644eacc1f0fd89d535ed36bf Mon Sep 17 00:00:00 2001 From: Andrew Jones Date: Tue, 4 Jun 2013 10:49:48 +0200 Subject: [PATCH] e1000: cleanup process_tx_desc Coverity complains about two overruns in process_tx_desc(). The complaints are false positives, but we might as well eliminate them. The problem is that "hdr" is defined as an unsigned int, but then used to offset an array of size 65536, and another of size 256 bytes. hdr will actually never be greater than 255 though, as it's assigned only once and to the value of tp->hdr_len, which is an uint8_t. This patch simply gets rid of hdr, replacing it with tp->hdr_len, which makes it consistent with all other tp member use in the function. v2: - also cleanup coding style issues in the touched lines Signed-off-by: Andrew Jones Signed-off-by: Michael S. Tsirkin --- hw/net/e1000.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/hw/net/e1000.c b/hw/net/e1000.c index e6f46f0c51..620f947134 100644 --- a/hw/net/e1000.c +++ b/hw/net/e1000.c @@ -556,7 +556,7 @@ process_tx_desc(E1000State *s, struct e1000_tx_desc *dp) uint32_t txd_lower = le32_to_cpu(dp->lower.data); uint32_t dtype = txd_lower & (E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D); unsigned int split_size = txd_lower & 0xffff, bytes, sz, op; - unsigned int msh = 0xfffff, hdr = 0; + unsigned int msh = 0xfffff; uint64_t addr; struct e1000_context_desc *xp = (struct e1000_context_desc *)dp; struct e1000_tx *tp = &s->tx; @@ -603,8 +603,7 @@ process_tx_desc(E1000State *s, struct e1000_tx_desc *dp) addr = le64_to_cpu(dp->buffer_addr); if (tp->tse && tp->cptse) { - hdr = tp->hdr_len; - msh = hdr + tp->mss; + msh = tp->hdr_len + tp->mss; do { bytes = split_size; if (tp->size + bytes > msh) @@ -612,14 +611,16 @@ process_tx_desc(E1000State *s, struct e1000_tx_desc *dp) bytes = MIN(sizeof(tp->data) - tp->size, bytes); pci_dma_read(&s->dev, addr, tp->data + tp->size, bytes); - if ((sz = tp->size + bytes) >= hdr && tp->size < hdr) - memmove(tp->header, tp->data, hdr); + sz = tp->size + bytes; + if (sz >= tp->hdr_len && tp->size < tp->hdr_len) { + memmove(tp->header, tp->data, tp->hdr_len); + } tp->size = sz; addr += bytes; if (sz == msh) { xmit_seg(s); - memmove(tp->data, tp->header, hdr); - tp->size = hdr; + memmove(tp->data, tp->header, tp->hdr_len); + tp->size = tp->hdr_len; } } while (split_size -= bytes); } else if (!tp->tse && tp->cptse) { @@ -633,8 +634,9 @@ process_tx_desc(E1000State *s, struct e1000_tx_desc *dp) if (!(txd_lower & E1000_TXD_CMD_EOP)) return; - if (!(tp->tse && tp->cptse && tp->size < hdr)) + if (!(tp->tse && tp->cptse && tp->size < tp->hdr_len)) { xmit_seg(s); + } tp->tso_frames = 0; tp->sum_needed = 0; tp->vlan_needed = 0; -- 2.11.4.GIT