This is a note to let you know that I've just added the patch titled i40e: Fix flow for IPv6 next header (extension header) to the 5.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: i40e-fix-flow-for-ipv6-next-header-extension-header.patch and it can be found in the queue-5.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 6736ea036396cafb43b93ea3fb523563748e0b65 Author: Slawomir Laba <slawomirx.laba@xxxxxxxxx> Date: Thu Sep 10 07:57:04 2020 +0000 i40e: Fix flow for IPv6 next header (extension header) [ 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@xxxxxxxxx> Signed-off-by: Przemyslaw Patynowski <przemyslawx.patynowski@xxxxxxxxx> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@xxxxxxxxx> Tested-by: Tony Brelinski <tonyx.brelinski@xxxxxxxxx> Signed-off-by: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c index 4aca637d4a23c..32d97315f3f52 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c @@ -3113,13 +3113,16 @@ 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 */