diff mbox series

[04/11] xfrm: Silence warnings triggerable by bad packets

Message ID 20230815095310.3310160-5-steffen.klassert@secunet.com (mailing list archive)
State Accepted
Delegated to: Netdev Maintainers
Headers show
Series [01/11] net: xfrm: Fix xfrm_address_filter OOB read | expand

Checks

Context Check Description
netdev/series_format warning Pull request is its own cover letter; 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: 1335 this patch: 1335
netdev/cc_maintainers warning 2 maintainers not CCed: pabeni@redhat.com edumazet@google.com
netdev/build_clang success Errors and warnings before: 1353 this patch: 1353
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 Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 1358 this patch: 1358
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 58 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Steffen Klassert Aug. 15, 2023, 9:53 a.m. UTC 
From: Herbert Xu <herbert@gondor.apana.org.au>

After the elimination of inner modes, a couple of warnings that
were previously unreachable can now be triggered by malformed
inbound packets.

Fix this by:

1. Moving the setting of skb->protocol into the decap functions.
2. Returning -EINVAL when unexpected protocol is seen.

Reported-by: Maciej Żenczykowski<maze@google.com>
Fixes: 5f24f41e8ea6 ("xfrm: Remove inner/outer modes from input path")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/xfrm/xfrm_input.c | 22 +++++++++-------------
 1 file changed, 9 insertions(+), 13 deletions(-)
diff mbox series

Patch

diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 815b38080401..d5ee96789d4b 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -180,6 +180,8 @@  static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
 	int optlen = 0;
 	int err = -EINVAL;
 
+	skb->protocol = htons(ETH_P_IP);
+
 	if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
 		struct ip_beet_phdr *ph;
 		int phlen;
@@ -232,6 +234,8 @@  static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int err = -EINVAL;
 
+	skb->protocol = htons(ETH_P_IP);
+
 	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
 		goto out;
 
@@ -267,6 +271,8 @@  static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int err = -EINVAL;
 
+	skb->protocol = htons(ETH_P_IPV6);
+
 	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
 		goto out;
 
@@ -296,6 +302,8 @@  static int xfrm6_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
 	int size = sizeof(struct ipv6hdr);
 	int err;
 
+	skb->protocol = htons(ETH_P_IPV6);
+
 	err = skb_cow_head(skb, size + skb->mac_len);
 	if (err)
 		goto out;
@@ -346,6 +354,7 @@  xfrm_inner_mode_encap_remove(struct xfrm_state *x,
 			return xfrm6_remove_tunnel_encap(x, skb);
 		break;
 		}
+		return -EINVAL;
 	}
 
 	WARN_ON_ONCE(1);
@@ -366,19 +375,6 @@  static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 		return -EAFNOSUPPORT;
 	}
 
-	switch (XFRM_MODE_SKB_CB(skb)->protocol) {
-	case IPPROTO_IPIP:
-	case IPPROTO_BEETPH:
-		skb->protocol = htons(ETH_P_IP);
-		break;
-	case IPPROTO_IPV6:
-		skb->protocol = htons(ETH_P_IPV6);
-		break;
-	default:
-		WARN_ON_ONCE(1);
-		break;
-	}
-
 	return xfrm_inner_mode_encap_remove(x, skb);
 }