[PATCH bpf-next v4 1/2] bpf: Fix bpf_get/setsockopt to tos for ipv4-mapped ipv6 socket
From: Leon Hwang <hidden>
Date: 2026-06-13 16:25:17
Also in:
bpf, linux-kselftest, lkml
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [networking] (tcx & tc bpf, sock_addr), networking [general], the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
When TCP over IPv4 via INET6 API, bpf_get/setsockopt with ipv4 will
fail, because sk->sk_family is AF_INET6. With ipv6 will success, not
take effect, because inet_csk(sk)->icsk_af_ops is ipv6_mapped and
use ip_queue_xmit, inet_sk(sk)->tos.
To relax this restriction, allow getting/setting tos for those possible
ipv4-mapped ipv6 sockets.
Fixes: ee7f1e1302f5 ("bpf: Change bpf_setsockopt(SOL_IP) to reuse do_ip_setsockopt()")
Signed-off-by: Feng Zhou <redacted>
Signed-off-by: Leon Hwang <redacted>
---
net/core/filter.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/net/core/filter.c b/net/core/filter.c
index 9590877b0714..57b00c6cc8cc 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c@@ -5544,11 +5544,24 @@ static int sol_tcp_sockopt(struct sock *sk, int optname, KERNEL_SOCKPTR(optval), *optlen); } +static bool sk_allows_sol_ip_sockopt(struct sock *sk) +{ + switch (sk->sk_family) { + case AF_INET: + return true; + case AF_INET6: + /* Allow getting/setting sockopt for possible ipv4-mapped ipv6 socket. */ + return sk->sk_type != SOCK_RAW && !ipv6_only_sock(sk); + default: + return false; + } +} + static int sol_ip_sockopt(struct sock *sk, int optname, char *optval, int *optlen, bool getopt) { - if (sk->sk_family != AF_INET) + if (!sk_allows_sol_ip_sockopt(sk)) return -EINVAL; switch (optname) {
--
2.54.0