From 37a9a8df8ce9de6ea73349c9ac8bdf6ba4ec4f70 Mon Sep 17 00:00:00 2001 From: Stephen Smalley Date: Wed, 10 Jun 2015 08:44:59 -0400 Subject: net/unix: support SCM_SECURITY for stream sockets SCM_SECURITY was originally only implemented for datagram sockets, not for stream sockets. However, SCM_CREDENTIALS is supported on Unix stream sockets. For consistency, implement Unix stream support for SCM_SECURITY as well. Also clean up the existing code and get rid of the superfluous UNIXSID macro. Motivated by https://bugzilla.redhat.com/show_bug.cgi?id=1224211, where systemd was using SCM_CREDENTIALS and assumed wrongly that SCM_SECURITY was also supported on Unix stream sockets. Signed-off-by: Stephen Smalley Acked-by: Paul Moore Signed-off-by: David S. Miller --- net/unix/af_unix.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) (limited to 'net/unix') diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index f25e1675b865..03ee4d359f6a 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -140,12 +140,17 @@ static struct hlist_head *unix_sockets_unbound(void *addr) #ifdef CONFIG_SECURITY_NETWORK static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) { - memcpy(UNIXSID(skb), &scm->secid, sizeof(u32)); + UNIXCB(skb).secid = scm->secid; } static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) { - scm->secid = *UNIXSID(skb); + scm->secid = UNIXCB(skb).secid; +} + +static inline bool unix_secdata_eq(struct scm_cookie *scm, struct sk_buff *skb) +{ + return (scm->secid == UNIXCB(skb).secid); } #else static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) @@ -153,6 +158,11 @@ static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb) static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb) { } + +static inline bool unix_secdata_eq(struct scm_cookie *scm, struct sk_buff *skb) +{ + return true; +} #endif /* CONFIG_SECURITY_NETWORK */ /* @@ -1414,6 +1424,7 @@ static int unix_scm_to_skb(struct scm_cookie *scm, struct sk_buff *skb, bool sen UNIXCB(skb).uid = scm->creds.uid; UNIXCB(skb).gid = scm->creds.gid; UNIXCB(skb).fp = NULL; + unix_get_secdata(scm, skb); if (scm->fp && send_fds) err = unix_attach_fds(scm, skb); @@ -1509,7 +1520,6 @@ static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg, if (err < 0) goto out_free; max_level = err + 1; - unix_get_secdata(&scm, skb); skb_put(skb, len - data_len); skb->data_len = data_len; @@ -2118,11 +2128,13 @@ unlock: /* Never glue messages from different writers */ if ((UNIXCB(skb).pid != scm.pid) || !uid_eq(UNIXCB(skb).uid, scm.creds.uid) || - !gid_eq(UNIXCB(skb).gid, scm.creds.gid)) + !gid_eq(UNIXCB(skb).gid, scm.creds.gid) || + !unix_secdata_eq(&scm, skb)) break; } else if (test_bit(SOCK_PASSCRED, &sock->flags)) { /* Copy credentials */ scm_set_cred(&scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid); + unix_set_secdata(&scm, skb); check_creds = true; } -- cgit v1.2.3-59-g8ed1b