From: Ido Schimmel Date: Wed, 4 Jun 2025 11:32:52 +0000 (+0300) Subject: seg6: Fix validation of nexthop addresses X-Git-Url: http://git.monstr.eu/?a=commitdiff_plain;h=7632fedb266d93ed0ed9f487133e6c6314a9b2d1;p=linux-2.6-microblaze.git seg6: Fix validation of nexthop addresses The kernel currently validates that the length of the provided nexthop address does not exceed the specified length. This can lead to the kernel reading uninitialized memory if user space provided a shorter length than the specified one. Fix by validating that the provided length exactly matches the specified one. Fixes: d1df6fd8a1d2 ("ipv6: sr: define core operations for seg6local lightweight tunnel") Reviewed-by: Petr Machata Signed-off-by: Ido Schimmel Reviewed-by: David Ahern Link: https://patch.msgid.link/20250604113252.371528-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski --- diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c index ac1dbd492c22..a11a02b4ba95 100644 --- a/net/ipv6/seg6_local.c +++ b/net/ipv6/seg6_local.c @@ -1644,10 +1644,8 @@ static const struct nla_policy seg6_local_policy[SEG6_LOCAL_MAX + 1] = { [SEG6_LOCAL_SRH] = { .type = NLA_BINARY }, [SEG6_LOCAL_TABLE] = { .type = NLA_U32 }, [SEG6_LOCAL_VRFTABLE] = { .type = NLA_U32 }, - [SEG6_LOCAL_NH4] = { .type = NLA_BINARY, - .len = sizeof(struct in_addr) }, - [SEG6_LOCAL_NH6] = { .type = NLA_BINARY, - .len = sizeof(struct in6_addr) }, + [SEG6_LOCAL_NH4] = NLA_POLICY_EXACT_LEN(sizeof(struct in_addr)), + [SEG6_LOCAL_NH6] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), [SEG6_LOCAL_IIF] = { .type = NLA_U32 }, [SEG6_LOCAL_OIF] = { .type = NLA_U32 }, [SEG6_LOCAL_BPF] = { .type = NLA_NESTED },