From: Lukasz Pawelczyk <l.pawelczyk@samsung.com>
Date: Wed, 26 Nov 2014 14:31:07 +0000 (+0100)
Subject: BACKPORT: smack: fix logic in smack_inode_init_security function
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b6e06f49facaa8a045a5ff9638a35479d989148f;p=platform%2Fkernel%2Flinux-stable.git

BACKPORT: smack: fix logic in smack_inode_init_security function

In principle if this function was called with "value" == NULL and "len"
not NULL it could return different results for the "len" compared to a
case where "name" was not NULL. This is a hypothetical case that does
not exist in the kernel, but it's a logic bug nonetheless.

Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@samsung.com>
(cherry-picked from upstream 68390ccf8b0a3470032f053d50379cfd49fbe952)
---

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index ef1e935de508..fc3070e0a008 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -803,7 +803,7 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir,
 			return -ENOMEM;
 	}
 
-	if (value) {
+	if (value && len) {
 		rcu_read_lock();
 		may = smk_access_entry(skp->smk_known, dsp->smk_known,
 				       &skp->smk_rules);
@@ -824,10 +824,9 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir,
 		*value = kstrdup(isp->smk_known, GFP_NOFS);
 		if (*value == NULL)
 			return -ENOMEM;
-	}
 
-	if (len)
 		*len = strlen(isp->smk_known);
+	}
 
 	return 0;
 }