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linux-kernel: [PATCH 14/20] SELinux: drop load_mutex in security

[PATCH 14/20] SELinux: drop load_mutex in security_load_policy

From: James Morris <jmorris_at_nospam>
Date: Mon Jul 07 2008 - 16:42:16 GMT
To: linux-security-module@vger.kernel.org


From: Eric Paris <eparis@redhat.com>

We used to protect against races of policy load in security_load_policy by using the load_mutex. Since then we have added a new mutex, sel_mutex, in sel_write_load() which is always held across all calls to security_load_policy we are covered and can safely just drop this one.

Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org> --- security/selinux/ss/services.c | 14 +------------- 1 files changed, 1 insertions(+), 13 deletions(-) diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index f26a8ca..543fd0f 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c
@@ -71,7 +71,6 @@ int selinux_policycap_openperm;
extern const struct selinux_class_perm selinux_class_perm; static DEFINE_RWLOCK(policy_rwlock); -static DEFINE_MUTEX(load_mutex); static struct sidtab sidtab; struct policydb policydb;
@@ -1453,17 +1452,13 @@ int security_load_policy(void *data, size_t len)
int rc = 0; struct policy_file file = { data, len }, *fp = &file; - mutex_lock(&load_mutex); - if (!ss_initialized) { avtab_cache_init(); if (policydb_read(&policydb, fp)) { - mutex_unlock(&load_mutex); avtab_cache_destroy(); return -EINVAL; } if (policydb_load_isids(&policydb, &sidtab)) { - mutex_unlock(&load_mutex); policydb_destroy(&policydb); avtab_cache_destroy(); return -EINVAL;
@@ -1472,7 +1467,6 @@ int security_load_policy(void *data, size_t len)
if (validate_classes(&policydb)) { printk(KERN_ERR "SELinux: the definition of a class is incorrect\n"); - mutex_unlock(&load_mutex); sidtab_destroy(&sidtab); policydb_destroy(&policydb); avtab_cache_destroy();
@@ -1482,7 +1476,6 @@ int security_load_policy(void *data, size_t len)
policydb_loaded_version = policydb.policyvers; ss_initialized = 1; seqno = ++latest_granting; - mutex_unlock(&load_mutex); selinux_complete_init(); avc_ss_reset(seqno); selnl_notify_policyload(seqno);
@@ -1495,13 +1488,10 @@ int security_load_policy(void *data, size_t len)
sidtab_hash_eval(&sidtab, "sids"); #endif - if (policydb_read(&newpolicydb, fp)) { - mutex_unlock(&load_mutex); + if (policydb_read(&newpolicydb, fp)) return -EINVAL; - } if (sidtab_init(&newsidtab)) { - mutex_unlock(&load_mutex); policydb_destroy(&newpolicydb); return -ENOMEM; }
@@ -1549,7 +1539,6 @@ int security_load_policy(void *data, size_t len)
seqno = ++latest_granting; policydb_loaded_version = policydb.policyvers; write_unlock_irq(&policy_rwlock); - mutex_unlock(&load_mutex); /* Free the old policydb and SID table. */ policydb_destroy(&oldpolicydb);
@@ -1563,7 +1552,6 @@ int security_load_policy(void *data, size_t len)
return 0; err: - mutex_unlock(&load_mutex); sidtab_destroy(&newsidtab); policydb_destroy(&newpolicydb); return rc; -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html