Patch "selinux: Clean up initialization of isec->sclass" has been added to the 4.9-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    selinux: Clean up initialization of isec->sclass

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     selinux-clean-up-initialization-of-isec-sclass.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 240b4571b84b1a241e38d37784b77202f9babe66
Author: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Date:   Thu Nov 10 22:18:29 2016 +0100

    selinux: Clean up initialization of isec->sclass
    
    commit 13457d073c29da92001f6ee809075eaa8757fb96 upstream.
    
    Now that isec->initialized == LABEL_INITIALIZED implies that
    isec->sclass is valid, skip such inodes immediately in
    inode_doinit_with_dentry.
    
    For the remaining inodes, initialize isec->sclass at the beginning of
    inode_doinit_with_dentry to simplify the code.
    
    Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
    Signed-off-by: Paul Moore <paul@xxxxxxxxxxxxxx>
    Signed-off-by: Alexander Grund <theflamefire89@xxxxxxxxx>
    Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 1997d87b35d5..d21b95a848b8 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1395,12 +1395,15 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
 	int rc = 0;
 
 	if (isec->initialized == LABEL_INITIALIZED)
-		goto out;
+		return 0;
 
 	mutex_lock(&isec->lock);
 	if (isec->initialized == LABEL_INITIALIZED)
 		goto out_unlock;
 
+	if (isec->sclass == SECCLASS_FILE)
+		isec->sclass = inode_mode_to_security_class(inode->i_mode);
+
 	sbsec = inode->i_sb->s_security;
 	if (!(sbsec->flags & SE_SBINITIALIZED)) {
 		/* Defer initialization until selinux_complete_init,
@@ -1518,7 +1521,6 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
 		isec->sid = sbsec->sid;
 
 		/* Try to obtain a transition SID. */
-		isec->sclass = inode_mode_to_security_class(inode->i_mode);
 		rc = security_transition_sid(isec->task_sid, sbsec->sid,
 					     isec->sclass, NULL, &sid);
 		if (rc)
@@ -1554,7 +1556,6 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
 			 */
 			if (!dentry)
 				goto out_unlock;
-			isec->sclass = inode_mode_to_security_class(inode->i_mode);
 			rc = selinux_genfs_get_sid(dentry, isec->sclass,
 						   sbsec->flags, &sid);
 			dput(dentry);
@@ -1569,9 +1570,6 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
 
 out_unlock:
 	mutex_unlock(&isec->lock);
-out:
-	if (isec->sclass == SECCLASS_FILE)
-		isec->sclass = inode_mode_to_security_class(inode->i_mode);
 	return rc;
 }