Re: [PATCH] smack: Guard smack_ipv6_lock definition within a SMACK_IPV6_PORT_LABELING block
From: Casey Schaufler <casey@schaufler-ca.com>
Date: 2021-09-15 22:13:04
On 9/10/2021 2:45 AM, Sebastian Andrzej Siewior wrote:
The mutex smack_ipv6_lock is only used with the SMACK_IPV6_PORT_LABELING block but its definition is outside of the block. This leads to a defined-but-not-used warning on PREEMPT_RT. Moving smack_ipv6_lock down to the block where it is used where it used raises the question why is smk_ipv6_port_list read if nothing is added to it. Turns out, only smk_ipv6_port_check() is using it outside of an ifdef SMACK_IPV6_PORT_LABELING block. However two of three caller invoke smk_ipv6_port_check() from a ifdef block and only one is using __is_defined() macro which requires the function and smk_ipv6_port_list to be around. Put the lock and list inside an ifdef SMACK_IPV6_PORT_LABELING block to avoid the warning regarding unused mutex. Extend the ifdef-block to also cover smk_ipv6_port_check(). Make smack_socket_connect() use ifdef instead of __is_defined() to avoid complains about missing function. Cc: Casey Schaufler <casey@schaufler-ca.com>
This is the Smack maintainer, to whom you should send the next revision.
quoted hunk ↗ jump to hunk
Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- security/smack/smack_lsm.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index cacbe75185194..fd9e6b54907ee 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c@@ -51,8 +51,10 @@ #define SMK_RECEIVING 1 #define SMK_SENDING 2 +#ifdef SMACK_IPV6_PORT_LABELING static DEFINE_MUTEX(smack_ipv6_lock); static LIST_HEAD(smk_ipv6_port_list); +#endif struct kmem_cache *smack_rule_cache; int smack_enabled __initdata;@@ -2603,7 +2605,6 @@ 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@@ -2666,6 +2667,7 @@ static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address, return smk_ipv6_check(skp, object, address, act); } +#endif /** * smack_inode_setsecurity - set smack xattrs@@ -2852,8 +2854,9 @@ static int smack_socket_connect(struct socket *sock, struct sockaddr *sap, rc = smk_ipv6_check(ssp->smk_out, rsp, sip, SMK_CONNECTING); } - if (__is_defined(SMACK_IPV6_PORT_LABELING)) +#ifdef SMACK_IPV6_PORT_LABELING rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING); +#endif
Fix the indentation. Also, the patch came through with some html artifacts. Please fix the indentation and resubmit. Thank you.
return rc; }