kernel: smack security backport from kernel 4

Here is the backport of all patches relating to smack support
on kernel side. For more details, see file:

  meta-rcar-gen2/recipes-kernel/linux/linux-renesas/smack/README

Please note that patches are applied only if "smack" is in the
ditro features. Here are the 2 lines to add in the local.conf

OVERRIDES .= ":smack"
DISTRO_FEATURES_append = " smack"

Change-Id: I147a3532aec531f977d6ec34c576261835711f1e
Signed-off-by: Yannick GICQUEL <yannick.gicquel@iot.bzh>
Signed-off-by: José Bollo <jose.bollo@iot.bzh>

1 files changed, 54 insertions, 0 deletions

diff --git a/meta-rcar-gen2/recipes-kernel/linux/linux-renesas/smack/0036-Smack-remove-unneeded-NULL-termination-from-securtit.patch b/meta-rcar-gen2/recipes-kernel/linux/linux-renesas/smack/0036-Smack-remove-unneeded-NULL-termination-from-securtit.patch
new file mode 100644
index 0000000..2c72253
--- /dev/null
+++ b/meta-rcar-gen2/recipes-kernel/linux/linux-renesas/smack/0036-Smack-remove-unneeded-NULL-termination-from-securtit.patch
@@ -0,0 +1,54 @@
+From a48c9922ebf7553ec8bcecb9a41e04e120c454ec Mon Sep 17 00:00:00 2001
+From: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
+Date: Thu, 7 Aug 2014 20:52:49 +0400
+Subject: [PATCH 36/54] Smack: remove unneeded NULL-termination from securtity
+ label
+
+Values of extended attributes are stored as binary blobs. NULL-termination
+of them isn't required. It just wastes disk space and confuses command-line
+tools like getfattr because they have to print that zero byte at the end.
+
+This patch removes terminating zero byte from initial security label in
+smack_inode_init_security and cuts it out in function smack_inode_getsecurity
+which is used by syscall getxattr. This change seems completely safe, because
+function smk_parse_smack ignores everything after first zero byte.
+
+Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
+---
+ security/smack/smack_lsm.c | 6 +++---
+ 1 file changed, 3 insertions(+), 3 deletions(-)
+
+diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
+index 8d23c23..1befb0a 100644
+--- a/security/smack/smack_lsm.c
++++ b/security/smack/smack_lsm.c
+@@ -672,7 +672,7 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir,
+ 	}
+ 
+ 	if (len)
+-		*len = strlen(isp) + 1;
++		*len = strlen(isp);
+ 
+ 	return 0;
+ }
+@@ -1076,7 +1076,7 @@ static int smack_inode_getsecurity(const struct inode *inode,
+ 
+ 	if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
+ 		isp = smk_of_inode(inode);
+-		ilen = strlen(isp) + 1;
++		ilen = strlen(isp);
+ 		*buffer = isp;
+ 		return ilen;
+ 	}
+@@ -1101,7 +1101,7 @@ static int smack_inode_getsecurity(const struct inode *inode,
+ 	else
+ 		return -EOPNOTSUPP;
+ 
+-	ilen = strlen(isp) + 1;
++	ilen = strlen(isp);
+ 	if (rc == 0) {
+ 		*buffer = isp;
+ 		rc = ilen;
+-- 
+2.1.4
+