diff mbox series

[nf-next,3/6] netfilter: bridge: move pskb_trim_rcsum out of br_nf_check_hbh_len

Message ID 688b6037c640efeb6141d4646cc9dc1b657796e7.1677888566.git.lucien.xin@gmail.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series netfilter: handle ipv6 jumbo packets properly for bridge ovs and tc | expand

Checks

Context Check Description
netdev/series_format warning Target tree name not specified in the subject
netdev/tree_selection success Guessed tree name to be net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 2 maintainers not CCed: coreteam@netfilter.org bridge@lists.linux-foundation.org
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 63 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Xin Long March 4, 2023, 12:12 a.m. UTC 
br_nf_check_hbh_len() is a function to check the Hop-by-hop option
header, and shouldn't do pskb_trim_rcsum() there. This patch is to
pass pkt_len out to br_validate_ipv6() and do pskb_trim_rcsum()
after calling br_validate_ipv6() instead.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 net/bridge/br_netfilter_ipv6.c | 33 ++++++++++++++-------------------
 1 file changed, 14 insertions(+), 19 deletions(-)

Comments

Simon Horman March 6, 2023, 4:26 p.m. UTC | #1 
On Fri, Mar 03, 2023 at 07:12:39PM -0500, Xin Long wrote:
> br_nf_check_hbh_len() is a function to check the Hop-by-hop option
> header, and shouldn't do pskb_trim_rcsum() there. This patch is to
> pass pkt_len out to br_validate_ipv6() and do pskb_trim_rcsum()
> after calling br_validate_ipv6() instead.
> 
> Signed-off-by: Xin Long <lucien.xin@gmail.com>

Reviewed-by: Simon Horman <simon.horman@corigine.com>

> ---
>  net/bridge/br_netfilter_ipv6.c | 33 ++++++++++++++-------------------
>  1 file changed, 14 insertions(+), 19 deletions(-)
> 
> diff --git a/net/bridge/br_netfilter_ipv6.c b/net/bridge/br_netfilter_ipv6.c
> index 50f564c33551..07289e4f3213 100644
> --- a/net/bridge/br_netfilter_ipv6.c
> +++ b/net/bridge/br_netfilter_ipv6.c
> @@ -43,11 +43,11 @@
>  /* We only check the length. A bridge shouldn't do any hop-by-hop stuff
>   * anyway
>   */
> -static int br_nf_check_hbh_len(struct sk_buff *skb)
> +static int br_nf_check_hbh_len(struct sk_buff *skb, u32 *plen)
>  {
>  	int len, off = sizeof(struct ipv6hdr);
>  	unsigned char *nh;
> -	u32 pkt_len;
> +	u32 pkt_len = 0;
>  
>  	if (!pskb_may_pull(skb, off + 8))
>  		return -1;
> @@ -83,10 +83,6 @@ static int br_nf_check_hbh_len(struct sk_buff *skb)
>  				return -1;
>  			if (pkt_len > skb->len - sizeof(struct ipv6hdr))
>  				return -1;
> -			if (pskb_trim_rcsum(skb,
> -					    pkt_len + sizeof(struct ipv6hdr)))
> -				return -1;
> -			nh = skb_network_header(skb);

nit: Something you may want to consider if you spin a v2.

     It seems that pkt_len is only set here.
     So *plen could also be set here, simplifying the return path slightly.

     Also, if so, then a not entirely related clean-up would
     be to reduce the scope of pkt_len to this block.

>  		}
>  		off += optlen;
>  		len -= optlen;
> @@ -94,6 +90,8 @@ static int br_nf_check_hbh_len(struct sk_buff *skb)
>  	if (len)
>  		return -1;
>  
> +	if (pkt_len)
> +		*plen = pkt_len;
>  	return 0;
>  }
>  

...
Nikolay Aleksandrov March 7, 2023, 9:21 a.m. UTC | #2 
On 04/03/2023 02:12, Xin Long wrote:
> br_nf_check_hbh_len() is a function to check the Hop-by-hop option
> header, and shouldn't do pskb_trim_rcsum() there. This patch is to
> pass pkt_len out to br_validate_ipv6() and do pskb_trim_rcsum()
> after calling br_validate_ipv6() instead.
> 
> Signed-off-by: Xin Long <lucien.xin@gmail.com>
> ---
>  net/bridge/br_netfilter_ipv6.c | 33 ++++++++++++++-------------------
>  1 file changed, 14 insertions(+), 19 deletions(-)
> 

Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Aaron Conole March 7, 2023, 6:32 p.m. UTC | #3 
Xin Long <lucien.xin@gmail.com> writes:

> br_nf_check_hbh_len() is a function to check the Hop-by-hop option
> header, and shouldn't do pskb_trim_rcsum() there. This patch is to
> pass pkt_len out to br_validate_ipv6() and do pskb_trim_rcsum()
> after calling br_validate_ipv6() instead.
>
> Signed-off-by: Xin Long <lucien.xin@gmail.com>
> ---

Reviewed-by: Aaron Conole <aconole@redhat.com>

>  net/bridge/br_netfilter_ipv6.c | 33 ++++++++++++++-------------------
>  1 file changed, 14 insertions(+), 19 deletions(-)
>
> diff --git a/net/bridge/br_netfilter_ipv6.c b/net/bridge/br_netfilter_ipv6.c
> index 50f564c33551..07289e4f3213 100644
> --- a/net/bridge/br_netfilter_ipv6.c
> +++ b/net/bridge/br_netfilter_ipv6.c
> @@ -43,11 +43,11 @@
>  /* We only check the length. A bridge shouldn't do any hop-by-hop stuff
>   * anyway
>   */
> -static int br_nf_check_hbh_len(struct sk_buff *skb)
> +static int br_nf_check_hbh_len(struct sk_buff *skb, u32 *plen)
>  {
>  	int len, off = sizeof(struct ipv6hdr);
>  	unsigned char *nh;
> -	u32 pkt_len;
> +	u32 pkt_len = 0;
>  
>  	if (!pskb_may_pull(skb, off + 8))
>  		return -1;
> @@ -83,10 +83,6 @@ static int br_nf_check_hbh_len(struct sk_buff *skb)
>  				return -1;
>  			if (pkt_len > skb->len - sizeof(struct ipv6hdr))
>  				return -1;
> -			if (pskb_trim_rcsum(skb,
> -					    pkt_len + sizeof(struct ipv6hdr)))
> -				return -1;
> -			nh = skb_network_header(skb);
>  		}
>  		off += optlen;
>  		len -= optlen;
> @@ -94,6 +90,8 @@ static int br_nf_check_hbh_len(struct sk_buff *skb)
>  	if (len)
>  		return -1;
>  
> +	if (pkt_len)
> +		*plen = pkt_len;
>  	return 0;
>  }
>  
> @@ -116,22 +114,19 @@ int br_validate_ipv6(struct net *net, struct sk_buff *skb)
>  		goto inhdr_error;
>  
>  	pkt_len = ntohs(hdr->payload_len);
> +	if (hdr->nexthdr == NEXTHDR_HOP && br_nf_check_hbh_len(skb, &pkt_len))
> +		goto drop;
>  
> -	if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
> -		if (pkt_len + ip6h_len > skb->len) {
> -			__IP6_INC_STATS(net, idev,
> -					IPSTATS_MIB_INTRUNCATEDPKTS);
> -			goto drop;
> -		}
> -		if (pskb_trim_rcsum(skb, pkt_len + ip6h_len)) {
> -			__IP6_INC_STATS(net, idev,
> -					IPSTATS_MIB_INDISCARDS);
> -			goto drop;
> -		}
> -		hdr = ipv6_hdr(skb);
> +	if (pkt_len + ip6h_len > skb->len) {
> +		__IP6_INC_STATS(net, idev,
> +				IPSTATS_MIB_INTRUNCATEDPKTS);
> +		goto drop;
>  	}
> -	if (hdr->nexthdr == NEXTHDR_HOP && br_nf_check_hbh_len(skb))
> +	if (pskb_trim_rcsum(skb, pkt_len + ip6h_len)) {
> +		__IP6_INC_STATS(net, idev,
> +				IPSTATS_MIB_INDISCARDS);
>  		goto drop;
> +	}
>  
>  	memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
>  	/* No IP options in IPv6 header; however it should be
diff mbox series

Patch

diff --git a/net/bridge/br_netfilter_ipv6.c b/net/bridge/br_netfilter_ipv6.c
index 50f564c33551..07289e4f3213 100644
--- a/net/bridge/br_netfilter_ipv6.c
+++ b/net/bridge/br_netfilter_ipv6.c
@@ -43,11 +43,11 @@ 
 /* We only check the length. A bridge shouldn't do any hop-by-hop stuff
  * anyway
  */
-static int br_nf_check_hbh_len(struct sk_buff *skb)
+static int br_nf_check_hbh_len(struct sk_buff *skb, u32 *plen)
 {
 	int len, off = sizeof(struct ipv6hdr);
 	unsigned char *nh;
-	u32 pkt_len;
+	u32 pkt_len = 0;
 
 	if (!pskb_may_pull(skb, off + 8))
 		return -1;
@@ -83,10 +83,6 @@  static int br_nf_check_hbh_len(struct sk_buff *skb)
 				return -1;
 			if (pkt_len > skb->len - sizeof(struct ipv6hdr))
 				return -1;
-			if (pskb_trim_rcsum(skb,
-					    pkt_len + sizeof(struct ipv6hdr)))
-				return -1;
-			nh = skb_network_header(skb);
 		}
 		off += optlen;
 		len -= optlen;
@@ -94,6 +90,8 @@  static int br_nf_check_hbh_len(struct sk_buff *skb)
 	if (len)
 		return -1;
 
+	if (pkt_len)
+		*plen = pkt_len;
 	return 0;
 }
 
@@ -116,22 +114,19 @@  int br_validate_ipv6(struct net *net, struct sk_buff *skb)
 		goto inhdr_error;
 
 	pkt_len = ntohs(hdr->payload_len);
+	if (hdr->nexthdr == NEXTHDR_HOP && br_nf_check_hbh_len(skb, &pkt_len))
+		goto drop;
 
-	if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
-		if (pkt_len + ip6h_len > skb->len) {
-			__IP6_INC_STATS(net, idev,
-					IPSTATS_MIB_INTRUNCATEDPKTS);
-			goto drop;
-		}
-		if (pskb_trim_rcsum(skb, pkt_len + ip6h_len)) {
-			__IP6_INC_STATS(net, idev,
-					IPSTATS_MIB_INDISCARDS);
-			goto drop;
-		}
-		hdr = ipv6_hdr(skb);
+	if (pkt_len + ip6h_len > skb->len) {
+		__IP6_INC_STATS(net, idev,
+				IPSTATS_MIB_INTRUNCATEDPKTS);
+		goto drop;
 	}
-	if (hdr->nexthdr == NEXTHDR_HOP && br_nf_check_hbh_len(skb))
+	if (pskb_trim_rcsum(skb, pkt_len + ip6h_len)) {
+		__IP6_INC_STATS(net, idev,
+				IPSTATS_MIB_INDISCARDS);
 		goto drop;
+	}
 
 	memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
 	/* No IP options in IPv6 header; however it should be