From 0e81cfd971dc4833c699dcd8924e54a5021bc4e8 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Mon, 19 May 2025 13:57:57 -0700 Subject: af_unix: Move SOCK_PASS{CRED,PIDFD,SEC} to struct sock. As explained in the next patch, SO_PASSRIGHTS would have a problem if we assigned a corresponding bit to socket->flags, so it must be managed in struct sock. Mixing socket->flags and sk->sk_flags for similar options will look confusing, and sk->sk_flags does not have enough space on 32bit system. Also, as mentioned in commit 16e572626961 ("af_unix: dont send SCM_CREDENTIALS by default"), SOCK_PASSCRED and SOCK_PASSPID handling is known to be slow, and managing the flags in struct socket cannot avoid that for embryo sockets. Let's move SOCK_PASS{CRED,PIDFD,SEC} to struct sock. While at it, other SOCK_XXX flags in net.h are grouped as enum. Note that assign_bit() was atomic, so the writer side is moved down after lock_sock() in setsockopt(), but the bit is only read once in sendmsg() and recvmsg(), so lock_sock() is not needed there. Signed-off-by: Kuniyuki Iwashima Reviewed-by: Willem de Bruijn Signed-off-by: David S. Miller --- net/core/sock.c | 44 +++++++++++++++++++++++--------------------- 1 file changed, 23 insertions(+), 21 deletions(-) (limited to 'net/core/sock.c') diff --git a/net/core/sock.c b/net/core/sock.c index fd5f9d3873c1..381abf8f25b7 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1220,24 +1220,6 @@ int sk_setsockopt(struct sock *sk, int level, int optname, return 0; } return -EPERM; - case SO_PASSSEC: - if (!IS_ENABLED(CONFIG_SECURITY_NETWORK) || sk_may_scm_recv(sk)) - return -EOPNOTSUPP; - - assign_bit(SOCK_PASSSEC, &sock->flags, valbool); - return 0; - case SO_PASSCRED: - if (!sk_may_scm_recv(sk)) - return -EOPNOTSUPP; - - assign_bit(SOCK_PASSCRED, &sock->flags, valbool); - return 0; - case SO_PASSPIDFD: - if (!sk_is_unix(sk)) - return -EOPNOTSUPP; - - assign_bit(SOCK_PASSPIDFD, &sock->flags, valbool); - return 0; case SO_TYPE: case SO_PROTOCOL: case SO_DOMAIN: @@ -1568,6 +1550,26 @@ set_sndbuf: sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); break; + case SO_PASSCRED: + if (sk_may_scm_recv(sk)) + sk->sk_scm_credentials = valbool; + else + ret = -EOPNOTSUPP; + break; + + case SO_PASSSEC: + if (IS_ENABLED(CONFIG_SECURITY_NETWORK) && sk_may_scm_recv(sk)) + sk->sk_scm_security = valbool; + else + ret = -EOPNOTSUPP; + break; + + case SO_PASSPIDFD: + if (sk_is_unix(sk)) + sk->sk_scm_pidfd = valbool; + else + ret = -EOPNOTSUPP; + break; case SO_INCOMING_CPU: reuseport_update_incoming_cpu(sk, val); @@ -1867,14 +1869,14 @@ int sk_getsockopt(struct sock *sk, int level, int optname, if (!sk_may_scm_recv(sk)) return -EOPNOTSUPP; - v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); + v.val = sk->sk_scm_credentials; break; case SO_PASSPIDFD: if (!sk_is_unix(sk)) return -EOPNOTSUPP; - v.val = !!test_bit(SOCK_PASSPIDFD, &sock->flags); + v.val = sk->sk_scm_pidfd; break; case SO_PEERCRED: @@ -1974,7 +1976,7 @@ int sk_getsockopt(struct sock *sk, int level, int optname, if (!IS_ENABLED(CONFIG_SECURITY_NETWORK) || !sk_may_scm_recv(sk)) return -EOPNOTSUPP; - v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); + v.val = sk->sk_scm_security; break; case SO_PEERSEC: -- cgit v1.2.3