[PATCH 5.4 021/134] smack: avoid unused sip variable warning

From: Greg Kroah-Hartman
Date: Tue Jun 16 2020 - 11:36:47 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

[ Upstream commit 00720f0e7f288d29681d265c23b22bb0f0f4e5b4 ]

The mix of IS_ENABLED() and #ifdef checks has left a combination
that causes a warning about an unused variable:

security/smack/smack_lsm.c: In function 'smack_socket_connect':
security/smack/smack_lsm.c:2838:24: error: unused variable 'sip' [-Werror=unused-variable]
2838 | struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;

Change the code to use C-style checks consistently so the compiler
can handle it correctly.

Fixes: 87fbfffcc89b ("broken ping to ipv6 linklocal addresses on debian buster")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
security/smack/smack.h | 6 ------
security/smack/smack_lsm.c | 25 ++++++++-----------------
2 files changed, 8 insertions(+), 23 deletions(-)

diff --git a/security/smack/smack.h b/security/smack/smack.h
index 62529f382942..335d2411abe4 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -148,7 +148,6 @@ struct smk_net4addr {
struct smack_known *smk_label; /* label */
};

-#if IS_ENABLED(CONFIG_IPV6)
/*
* An entry in the table identifying IPv6 hosts.
*/
@@ -159,9 +158,7 @@ struct smk_net6addr {
int smk_masks; /* mask size */
struct smack_known *smk_label; /* label */
};
-#endif /* CONFIG_IPV6 */

-#ifdef SMACK_IPV6_PORT_LABELING
/*
* An entry in the table identifying ports.
*/
@@ -174,7 +171,6 @@ struct smk_port_label {
short smk_sock_type; /* Socket type */
short smk_can_reuse;
};
-#endif /* SMACK_IPV6_PORT_LABELING */

struct smack_known_list_elem {
struct list_head list;
@@ -335,9 +331,7 @@ extern struct smack_known smack_known_web;
extern struct mutex smack_known_lock;
extern struct list_head smack_known_list;
extern struct list_head smk_net4addr_list;
-#if IS_ENABLED(CONFIG_IPV6)
extern struct list_head smk_net6addr_list;
-#endif /* CONFIG_IPV6 */

extern struct mutex smack_onlycap_lock;
extern struct list_head smack_onlycap_list;
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index ad22066eba04..12c0fa85d9f8 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -51,10 +51,8 @@
#define SMK_RECEIVING 1
#define SMK_SENDING 2

-#ifdef SMACK_IPV6_PORT_LABELING
-DEFINE_MUTEX(smack_ipv6_lock);
+static DEFINE_MUTEX(smack_ipv6_lock);
static LIST_HEAD(smk_ipv6_port_list);
-#endif
static struct kmem_cache *smack_inode_cache;
struct kmem_cache *smack_rule_cache;
int smack_enabled;
@@ -2326,7 +2324,6 @@ static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip)
return NULL;
}

-#if IS_ENABLED(CONFIG_IPV6)
/*
* smk_ipv6_localhost - Check for local ipv6 host address
* @sip: the address
@@ -2394,7 +2391,6 @@ static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)

return NULL;
}
-#endif /* CONFIG_IPV6 */

/**
* smack_netlabel - Set the secattr on a socket
@@ -2483,7 +2479,6 @@ static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
return smack_netlabel(sk, sk_lbl);
}

-#if IS_ENABLED(CONFIG_IPV6)
/**
* smk_ipv6_check - check Smack access
* @subject: subject Smack label
@@ -2516,7 +2511,6 @@ static int smk_ipv6_check(struct smack_known *subject,
rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
return rc;
}
-#endif /* CONFIG_IPV6 */

#ifdef SMACK_IPV6_PORT_LABELING
/**
@@ -2605,6 +2599,7 @@ static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
mutex_unlock(&smack_ipv6_lock);
return;
}
+#endif

/**
* smk_ipv6_port_check - check Smack port access
@@ -2667,7 +2662,6 @@ static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,

return smk_ipv6_check(skp, object, address, act);
}
-#endif /* SMACK_IPV6_PORT_LABELING */

/**
* smack_inode_setsecurity - set smack xattrs
@@ -2842,24 +2836,21 @@ static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
return 0;
if (IS_ENABLED(CONFIG_IPV6) && sap->sa_family == AF_INET6) {
struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
-#ifdef SMACK_IPV6_SECMARK_LABELING
- struct smack_known *rsp;
-#endif
+ struct smack_known *rsp = NULL;

if (addrlen < SIN6_LEN_RFC2133)
return 0;
-#ifdef SMACK_IPV6_SECMARK_LABELING
- rsp = smack_ipv6host_label(sip);
+ if (__is_defined(SMACK_IPV6_SECMARK_LABELING))
+ rsp = smack_ipv6host_label(sip);
if (rsp != NULL) {
struct socket_smack *ssp = sock->sk->sk_security;

rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
SMK_CONNECTING);
}
-#endif
-#ifdef SMACK_IPV6_PORT_LABELING
- rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
-#endif
+ if (__is_defined(SMACK_IPV6_PORT_LABELING))
+ rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
+
return rc;
}
if (sap->sa_family != AF_INET || addrlen < sizeof(struct sockaddr_in))
--
2.25.1