[PATCH] SELinux: change isec semaphore to a mutex
This patch converts the remaining isec->sem into a mutex. Very similar
locking is provided as before only in the faster smaller mutex rather than a
semaphore. An out_unlock path is introduced rather than the conditional
unlocking found in the original code.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 14a7819..63ad57a 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -71,6 +71,7 @@
#include <linux/audit.h>
#include <linux/string.h>
#include <linux/selinux.h>
+#include <linux/mutex.h>
#include "avc.h"
#include "objsec.h"
@@ -185,7 +186,7 @@
return -ENOMEM;
memset(isec, 0, sizeof(*isec));
- init_MUTEX(&isec->sem);
+ mutex_init(&isec->lock);
INIT_LIST_HEAD(&isec->list);
isec->inode = inode;
isec->sid = SECINITSID_UNLABELED;
@@ -843,15 +844,13 @@
char *context = NULL;
unsigned len = 0;
int rc = 0;
- int hold_sem = 0;
if (isec->initialized)
goto out;
- down(&isec->sem);
- hold_sem = 1;
+ mutex_lock(&isec->lock);
if (isec->initialized)
- goto out;
+ goto out_unlock;
sbsec = inode->i_sb->s_security;
if (!sbsec->initialized) {
@@ -862,7 +861,7 @@
if (list_empty(&isec->list))
list_add(&isec->list, &sbsec->isec_head);
spin_unlock(&sbsec->isec_lock);
- goto out;
+ goto out_unlock;
}
switch (sbsec->behavior) {
@@ -885,7 +884,7 @@
printk(KERN_WARNING "%s: no dentry for dev=%s "
"ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
inode->i_ino);
- goto out;
+ goto out_unlock;
}
len = INITCONTEXTLEN;
@@ -893,7 +892,7 @@
if (!context) {
rc = -ENOMEM;
dput(dentry);
- goto out;
+ goto out_unlock;
}
rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
context, len);
@@ -903,7 +902,7 @@
NULL, 0);
if (rc < 0) {
dput(dentry);
- goto out;
+ goto out_unlock;
}
kfree(context);
len = rc;
@@ -911,7 +910,7 @@
if (!context) {
rc = -ENOMEM;
dput(dentry);
- goto out;
+ goto out_unlock;
}
rc = inode->i_op->getxattr(dentry,
XATTR_NAME_SELINUX,
@@ -924,7 +923,7 @@
"%d for dev=%s ino=%ld\n", __FUNCTION__,
-rc, inode->i_sb->s_id, inode->i_ino);
kfree(context);
- goto out;
+ goto out_unlock;
}
/* Map ENODATA to the default file SID */
sid = sbsec->def_sid;
@@ -960,7 +959,7 @@
isec->sclass,
&sid);
if (rc)
- goto out;
+ goto out_unlock;
isec->sid = sid;
break;
case SECURITY_FS_USE_MNTPOINT:
@@ -978,7 +977,7 @@
isec->sclass,
&sid);
if (rc)
- goto out;
+ goto out_unlock;
isec->sid = sid;
}
}
@@ -987,12 +986,11 @@
isec->initialized = 1;
+out_unlock:
+ mutex_unlock(&isec->lock);
out:
if (isec->sclass == SECCLASS_FILE)
isec->sclass = inode_mode_to_security_class(inode->i_mode);
-
- if (hold_sem)
- up(&isec->sem);
return rc;
}