diff mbox series

[PATCHv2,nf-next,1/6] netfilter: bridge: call pskb_may_pull in br_nf_check_hbh_len

Message ID 1395e96f22b8eb3abb0593af644ac687ac746591.1678224658.git.lucien.xin@gmail.com (mailing list archive)
State Awaiting Upstream
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: 20 this patch: 20
netdev/cc_maintainers warning 2 maintainers not CCed: bridge@lists.linux-foundation.org coreteam@netfilter.org
netdev/build_clang success Errors and warnings before: 18 this patch: 18
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: 20 this patch: 20
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 23 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 7, 2023, 9:31 p.m. UTC 
When checking Hop-by-hop option header, if the option data is in
nonlinear area, it should do pskb_may_pull instead of discarding
the skb as a bad IPv6 packet.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
---
 net/bridge/br_netfilter_ipv6.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/net/bridge/br_netfilter_ipv6.c b/net/bridge/br_netfilter_ipv6.c
index 6b07f30675bb..afd1c718b683 100644
--- a/net/bridge/br_netfilter_ipv6.c
+++ b/net/bridge/br_netfilter_ipv6.c
@@ -45,14 +45,18 @@ 
  */
 static int br_nf_check_hbh_len(struct sk_buff *skb)
 {
-	unsigned char *raw = (u8 *)(ipv6_hdr(skb) + 1);
+	int len, off = sizeof(struct ipv6hdr);
+	unsigned char *nh;
 	u32 pkt_len;
-	const unsigned char *nh = skb_network_header(skb);
-	int off = raw - nh;
-	int len = (raw[1] + 1) << 3;
 
-	if ((raw + len) - skb->data > skb_headlen(skb))
+	if (!pskb_may_pull(skb, off + 8))
 		goto bad;
+	nh = (unsigned char *)(ipv6_hdr(skb) + 1);
+	len = (nh[1] + 1) << 3;
+
+	if (!pskb_may_pull(skb, off + len))
+		goto bad;
+	nh = skb_network_header(skb);
 
 	off += 2;
 	len -= 2;