From: Slawomir Laba slawomirx.laba@intel.com
[ Upstream commit 92c6058024e87087cf1b99b0389d67c0a886360e ]
When a packet contains an IPv6 header with next header which is an extension header and not a protocol one, the kernel function skb_transport_header called with such sk_buff will return a pointer to the extension header and not to the TCP one.
The above explained call caused a problem with packet processing for skb with encapsulation for tunnel with I40E_TX_CTX_EXT_IP_IPV6. The extension header was not skipped at all.
The ipv6_skip_exthdr function does check if next header of the IPV6 header is an extension header and doesn't modify the l4_proto pointer if it points to a protocol header value so its safe to omit the comparison of exthdr and l4.hdr pointers. The ipv6_skip_exthdr can return value -1. This means that the skipping process failed and there is something wrong with the packet so it will be dropped.
Fixes: a3fd9d8876a5 ("i40e/i40evf: Handle IPv6 extension headers in checksum offload") Signed-off-by: Slawomir Laba slawomirx.laba@intel.com Signed-off-by: Przemyslaw Patynowski przemyslawx.patynowski@intel.com Reviewed-by: Aleksandr Loktionov aleksandr.loktionov@intel.com Tested-by: Tony Brelinski tonyx.brelinski@intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/i40e/i40e_txrx.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c index f47841f3a69d5..218aada8949d9 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c @@ -3093,13 +3093,16 @@ static int i40e_tx_enable_csum(struct sk_buff *skb, u32 *tx_flags,
l4_proto = ip.v4->protocol; } else if (*tx_flags & I40E_TX_FLAGS_IPV6) { + int ret; + tunnel |= I40E_TX_CTX_EXT_IP_IPV6;
exthdr = ip.hdr + sizeof(*ip.v6); l4_proto = ip.v6->nexthdr; - if (l4.hdr != exthdr) - ipv6_skip_exthdr(skb, exthdr - skb->data, - &l4_proto, &frag_off); + ret = ipv6_skip_exthdr(skb, exthdr - skb->data, + &l4_proto, &frag_off); + if (ret < 0) + return -1; }
/* define outer transport */