selinux: avoid implicit conversions in the AVC code

Use a consistent type of u32 for sequence numbers.

Use a non-negative and input parameter matching type for the hash
result.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: subject line tweaks]
Signed-off-by: Paul Moore <paul@paul-moore.com>

diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 1074db6..cd55479 100644 (file)
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -122,7 +122,7 @@ static struct kmem_cache *avc_xperms_data_cachep __ro_after_init;
 static struct kmem_cache *avc_xperms_decision_cachep __ro_after_init;
 static struct kmem_cache *avc_xperms_cachep __ro_after_init;
 
-static inline int avc_hash(u32 ssid, u32 tsid, u16 tclass)
+static inline u32 avc_hash(u32 ssid, u32 tsid, u16 tclass)
 {
        return (ssid ^ (tsid<<2) ^ (tclass<<4)) & (AVC_CACHE_SLOTS - 1);
 }
@@ -523,7 +523,7 @@ static void avc_node_populate(struct avc_node *node, u32 ssid, u32 tsid, u16 tcl
 static inline struct avc_node *avc_search_node(u32 ssid, u32 tsid, u16 tclass)
 {
        struct avc_node *node, *ret = NULL;
-       int hvalue;
+       u32 hvalue;
        struct hlist_head *head;
 
        hvalue = avc_hash(ssid, tsid, tclass);
@@ -566,7 +566,7 @@ static struct avc_node *avc_lookup(u32 ssid, u32 tsid, u16 tclass)
        return NULL;
 }
 
-static int avc_latest_notif_update(int seqno, int is_insert)
+static int avc_latest_notif_update(u32 seqno, int is_insert)
 {
        int ret = 0;
        static DEFINE_SPINLOCK(notif_lock);
@@ -609,7 +609,7 @@ static void avc_insert(u32 ssid, u32 tsid, u16 tclass,
                       struct av_decision *avd, struct avc_xperms_node *xp_node)
 {
        struct avc_node *pos, *node = NULL;
-       int hvalue;
+       u32 hvalue;
        unsigned long flag;
        spinlock_t *lock;
        struct hlist_head *head;
@@ -654,9 +654,9 @@ static void avc_audit_pre_callback(struct audit_buffer *ab, void *a)
 {
        struct common_audit_data *ad = a;
        struct selinux_audit_data *sad = ad->selinux_audit_data;
-       u32 av = sad->audited;
+       u32 av = sad->audited, perm;
        const char *const *perms;
-       int i, perm;
+       u32 i;
 
        audit_log_format(ab, "avc:  %s ", sad->denied ? "denied" : "granted");
 
@@ -833,7 +833,8 @@ static int avc_update_node(u32 event, u32 perms, u8 driver, u8 xperm, u32 ssid,
                           struct extended_perms_decision *xpd,
                           u32 flags)
 {
-       int hvalue, rc = 0;
+       u32 hvalue;
+       int rc = 0;
        unsigned long flag;
        struct avc_node *pos, *node, *orig = NULL;
        struct hlist_head *head;