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, 170 insertions, 0 deletions

diff --git a/meta-rcar-gen2/recipes-kernel/linux/linux-renesas/smack/0006-Security-Add-Hook-to-test-if-the-particular-xattr-is.patch b/meta-rcar-gen2/recipes-kernel/linux/linux-renesas/smack/0006-Security-Add-Hook-to-test-if-the-particular-xattr-is.patch
new file mode 100644
index 0000000..2539ff6
--- /dev/null
+++ b/meta-rcar-gen2/recipes-kernel/linux/linux-renesas/smack/0006-Security-Add-Hook-to-test-if-the-particular-xattr-is.patch
@@ -0,0 +1,170 @@
+From 2a47b333efc3a2cb768eaba9d35e1467b3bc6211 Mon Sep 17 00:00:00 2001
+From: David Quigley <dpquigl@davequigley.com>
+Date: Wed, 22 May 2013 12:50:35 -0400
+Subject: [PATCH 06/54] Security: Add Hook to test if the particular xattr is
+ part of a MAC model.
+
+The interface to request security labels from user space is the xattr
+interface. When requesting the security label from an NFS server it is
+important to make sure the requested xattr actually is a MAC label. This allows
+us to make sure that we get the desired semantics from the attribute instead of
+something else such as capabilities or a time based LSM.
+
+Acked-by: Eric Paris <eparis@redhat.com>
+Acked-by: James Morris <james.l.morris@oracle.com>
+Signed-off-by: Matthew N. Dodd <Matthew.Dodd@sparta.com>
+Signed-off-by: Miguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
+Signed-off-by: Phua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
+Signed-off-by: Khin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
+Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
+---
+ include/linux/security.h   | 14 ++++++++++++++
+ security/capability.c      |  6 ++++++
+ security/security.c        |  6 ++++++
+ security/selinux/hooks.c   |  6 ++++++
+ security/smack/smack_lsm.c | 11 +++++++++++
+ 5 files changed, 43 insertions(+)
+
+diff --git a/include/linux/security.h b/include/linux/security.h
+index 4686491..1d8fe3c 100644
+--- a/include/linux/security.h
++++ b/include/linux/security.h
+@@ -1313,6 +1313,13 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
+  *	@pages contains the number of pages.
+  *	Return 0 if permission is granted.
+  *
++ * @ismaclabel:
++ *	Check if the extended attribute specified by @name
++ *	represents a MAC label. Returns 1 if name is a MAC
++ *	attribute otherwise returns 0.
++ *	@name full extended attribute name to check against
++ *	LSM as a MAC label.
++ *
+  * @secid_to_secctx:
+  *	Convert secid to security context.  If secdata is NULL the length of
+  *	the result will be returned in seclen, but no secdata will be returned.
+@@ -1590,6 +1597,7 @@ struct security_operations {
+ 
+ 	int (*getprocattr) (struct task_struct *p, char *name, char **value);
+ 	int (*setprocattr) (struct task_struct *p, char *name, void *value, size_t size);
++	int (*ismaclabel) (const char *name);
+ 	int (*secid_to_secctx) (u32 secid, char **secdata, u32 *seclen);
+ 	int (*secctx_to_secid) (const char *secdata, u32 seclen, u32 *secid);
+ 	void (*release_secctx) (char *secdata, u32 seclen);
+@@ -1840,6 +1848,7 @@ void security_d_instantiate(struct dentry *dentry, struct inode *inode);
+ int security_getprocattr(struct task_struct *p, char *name, char **value);
+ int security_setprocattr(struct task_struct *p, char *name, void *value, size_t size);
+ int security_netlink_send(struct sock *sk, struct sk_buff *skb);
++int security_ismaclabel(const char *name);
+ int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
+ int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid);
+ void security_release_secctx(char *secdata, u32 seclen);
+@@ -2520,6 +2529,11 @@ static inline int security_netlink_send(struct sock *sk, struct sk_buff *skb)
+ 	return cap_netlink_send(sk, skb);
+ }
+ 
++static inline int security_ismaclabel(const char *name)
++{
++	return 0;
++}
++
+ static inline int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
+ {
+ 	return -EOPNOTSUPP;
+diff --git a/security/capability.c b/security/capability.c
+index 1728d4e..26e0d3d 100644
+--- a/security/capability.c
++++ b/security/capability.c
+@@ -816,6 +816,11 @@ static int cap_setprocattr(struct task_struct *p, char *name, void *value,
+ 	return -EINVAL;
+ }
+ 
++static int cap_ismaclabel(const char *name)
++{
++	return 0;
++}
++
+ static int cap_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
+ {
+ 	return -EOPNOTSUPP;
+@@ -1034,6 +1039,7 @@ void __init security_fixup_ops(struct security_operations *ops)
+ 	set_to_cap_if_null(ops, d_instantiate);
+ 	set_to_cap_if_null(ops, getprocattr);
+ 	set_to_cap_if_null(ops, setprocattr);
++	set_to_cap_if_null(ops, ismaclabel);
+ 	set_to_cap_if_null(ops, secid_to_secctx);
+ 	set_to_cap_if_null(ops, secctx_to_secid);
+ 	set_to_cap_if_null(ops, release_secctx);
+diff --git a/security/security.c b/security/security.c
+index a3dce87..bf919ce 100644
+--- a/security/security.c
++++ b/security/security.c
+@@ -1047,6 +1047,12 @@ int security_netlink_send(struct sock *sk, struct sk_buff *skb)
+ 	return security_ops->netlink_send(sk, skb);
+ }
+ 
++int security_ismaclabel(const char *name)
++{
++	return security_ops->ismaclabel(name);
++}
++EXPORT_SYMBOL(security_ismaclabel);
++
+ int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
+ {
+ 	return security_ops->secid_to_secctx(secid, secdata, seclen);
+diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
+index a7096e1..d2f4381 100644
+--- a/security/selinux/hooks.c
++++ b/security/selinux/hooks.c
+@@ -5526,6 +5526,11 @@ abort_change:
+ 	return error;
+ }
+ 
++static int selinux_ismaclabel(const char *name)
++{
++	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
++}
++
+ static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
+ {
+ 	return security_sid_to_context(secid, secdata, seclen);
+@@ -5763,6 +5768,7 @@ static struct security_operations selinux_ops = {
+ 	.getprocattr =			selinux_getprocattr,
+ 	.setprocattr =			selinux_setprocattr,
+ 
++	.ismaclabel =			selinux_ismaclabel,
+ 	.secid_to_secctx =		selinux_secid_to_secctx,
+ 	.secctx_to_secid =		selinux_secctx_to_secid,
+ 	.release_secctx =		selinux_release_secctx,
+diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
+index 6a08330..3f7682a 100644
+--- a/security/smack/smack_lsm.c
++++ b/security/smack/smack_lsm.c
+@@ -3640,6 +3640,16 @@ static void smack_audit_rule_free(void *vrule)
+ #endif /* CONFIG_AUDIT */
+ 
+ /**
++ * smack_ismaclabel - check if xattr @name references a smack MAC label
++ * @name: Full xattr name to check.
++ */
++static int smack_ismaclabel(const char *name)
++{
++	return (strcmp(name, XATTR_SMACK_SUFFIX) == 0);
++}
++
++
++/**
+  * smack_secid_to_secctx - return the smack label for a secid
+  * @secid: incoming integer
+  * @secdata: destination
+@@ -3836,6 +3846,7 @@ struct security_operations smack_ops = {
+ 	.audit_rule_free =		smack_audit_rule_free,
+ #endif /* CONFIG_AUDIT */
+ 
++	.ismaclabel =			smack_ismaclabel,
+ 	.secid_to_secctx = 		smack_secid_to_secctx,
+ 	.secctx_to_secid = 		smack_secctx_to_secid,
+ 	.release_secctx = 		smack_release_secctx,
+-- 
+2.1.4
+