diff options
| author | Eric Dumazet <edumazet@google.com> | 2026-04-16 10:35:05 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-04-18 12:09:52 -0700 |
| commit | f996edd7615e686ada141b7f3395025729ff8ccb (patch) | |
| tree | 48af59f58fda2d1a860a61652adac064766b7903 /net/ipv6 | |
| parent | dcf6d5e629db8f85bdea5c6c102f5bfd4b05bf44 (diff) | |
ipv6: fix possible UAF in icmpv6_rcv()
Caching saddr and daddr before pskb_pull() is problematic
since skb->head can change.
Remove these temporary variables:
- We only access &ipv6_hdr(skb)->saddr and &ipv6_hdr(skb)->daddr
when net_dbg_ratelimited() is called in the slow path.
- Avoid potential future misuse after pskb_pull() call.
Fixes: 4b3418fba0fe ("ipv6: icmp: include addresses in debug messages")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de>
Reviewed-by: Joe Damato <joe@dama.to>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260416103505.2380753-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/icmp.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c index 799d9e9ac45d..efb23807a026 100644 --- a/net/ipv6/icmp.c +++ b/net/ipv6/icmp.c @@ -1104,7 +1104,6 @@ static int icmpv6_rcv(struct sk_buff *skb) struct net *net = dev_net_rcu(skb->dev); struct net_device *dev = icmp6_dev(skb); struct inet6_dev *idev = __in6_dev_get(dev); - const struct in6_addr *saddr, *daddr; struct icmp6hdr *hdr; u8 type; @@ -1135,12 +1134,10 @@ static int icmpv6_rcv(struct sk_buff *skb) __ICMP6_INC_STATS(dev_net_rcu(dev), idev, ICMP6_MIB_INMSGS); - saddr = &ipv6_hdr(skb)->saddr; - daddr = &ipv6_hdr(skb)->daddr; - if (skb_checksum_validate(skb, IPPROTO_ICMPV6, ip6_compute_pseudo)) { net_dbg_ratelimited("ICMPv6 checksum failed [%pI6c > %pI6c]\n", - saddr, daddr); + &ipv6_hdr(skb)->saddr, + &ipv6_hdr(skb)->daddr); goto csum_error; } @@ -1220,7 +1217,8 @@ static int icmpv6_rcv(struct sk_buff *skb) break; net_dbg_ratelimited("icmpv6: msg of unknown type [%pI6c > %pI6c]\n", - saddr, daddr); + &ipv6_hdr(skb)->saddr, + &ipv6_hdr(skb)->daddr); /* * error of unknown type. |