From: Shigeru Yoshida <syoshida@redhat.com> stable inclusion from stable-v6.6.31 commit 68c8ba16ab712eb709c6bab80ff151079d11d97a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9UAZH CVE: CVE-2024-36903 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 4e13d3a9c25b7080f8a619f961e943fe08c2672c ] As it was done in commit fc1092f51567 ("ipv4: Fix uninit-value access in __ip_make_skb()") for IPv4, check FLOWI_FLAG_KNOWN_NH on fl6->flowi6_flags instead of testing HDRINCL on the socket to avoid a race condition which causes uninit-value access. Fixes: ea30388baebc ("ipv6: Fix an uninit variable access bug in __ip6_make_skb()") Signed-off-by: Shigeru Yoshida <syoshida@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> --- net/ipv6/ip6_output.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 53fe1375b147..fba789cbd215 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -2003,7 +2003,7 @@ struct sk_buff *__ip6_make_skb(struct sock *sk, u8 icmp6_type; if (sk->sk_socket->type == SOCK_RAW && - !inet_test_bit(HDRINCL, sk)) + !(fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH)) icmp6_type = fl6->fl6_icmp_type; else icmp6_type = icmp6_hdr(skb)->icmp6_type; -- 2.34.1