selinux: Implementation for inode_copy_up_xattr() hook

[linux-2.6-microblaze.git] / security / selinux / hooks.c

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index ec30880..a2d5108 100644 (file)
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2832,7 +2832,7 @@ static void selinux_inode_free_security(struct inode *inode)
 }
 
 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
-                                       struct qstr *name, void **ctx,
+                                       const struct qstr *name, void **ctx,
                                        u32 *ctxlen)
 {
        u32 newsid;
@@ -3293,6 +3293,41 @@ static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
        *secid = isec->sid;
 }
 
+static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
+{
+       u32 sid;
+       struct task_security_struct *tsec;
+       struct cred *new_creds = *new;
+
+       if (new_creds == NULL) {
+               new_creds = prepare_creds();
+               if (!new_creds)
+                       return -ENOMEM;
+       }
+
+       tsec = new_creds->security;
+       /* Get label from overlay inode and set it in create_sid */
+       selinux_inode_getsecid(d_inode(src), &sid);
+       tsec->create_sid = sid;
+       *new = new_creds;
+       return 0;
+}
+
+static int selinux_inode_copy_up_xattr(const char *name)
+{
+       /* The copy_up hook above sets the initial context on an inode, but we
+        * don't then want to overwrite it by blindly copying all the lower
+        * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
+        */
+       if (strcmp(name, XATTR_NAME_SELINUX) == 0)
+               return 1; /* Discard */
+       /*
+        * Any other attribute apart from SELINUX is not claimed, supported
+        * by selinux.
+        */
+       return -EOPNOTSUPP;
+}
+
 /* file security operations */
 
 static int selinux_revalidate_file_permission(struct file *file, int mask)
@@ -3984,7 +4019,7 @@ out:
        return ret;
 }
 
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+#if IS_ENABLED(CONFIG_IPV6)
 
 /* Returns error only if unable to parse addresses */
 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
@@ -4075,7 +4110,7 @@ static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
                                       &ad->u.net->v4info.daddr);
                goto okay;
 
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+#if IS_ENABLED(CONFIG_IPV6)
        case PF_INET6:
                ret = selinux_parse_skb_ipv6(skb, ad, proto);
                if (ret)
@@ -5029,7 +5064,7 @@ static unsigned int selinux_ipv4_forward(void *priv,
        return selinux_ip_forward(skb, state->in, PF_INET);
 }
 
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+#if IS_ENABLED(CONFIG_IPV6)
 static unsigned int selinux_ipv6_forward(void *priv,
                                         struct sk_buff *skb,
                                         const struct nf_hook_state *state)
@@ -5087,7 +5122,7 @@ static unsigned int selinux_ipv4_output(void *priv,
        return selinux_ip_output(skb, PF_INET);
 }
 
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+#if IS_ENABLED(CONFIG_IPV6)
 static unsigned int selinux_ipv6_output(void *priv,
                                        struct sk_buff *skb,
                                        const struct nf_hook_state *state)
@@ -5273,7 +5308,7 @@ static unsigned int selinux_ipv4_postroute(void *priv,
        return selinux_ip_postroute(skb, state->out, PF_INET);
 }
 
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+#if IS_ENABLED(CONFIG_IPV6)
 static unsigned int selinux_ipv6_postroute(void *priv,
                                           struct sk_buff *skb,
                                           const struct nf_hook_state *state)
@@ -6088,6 +6123,8 @@ static struct security_hook_list selinux_hooks[] = {
        LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
        LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
        LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
+       LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
+       LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
 
        LSM_HOOK_INIT(file_permission, selinux_file_permission),
        LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
@@ -6317,7 +6354,7 @@ static struct nf_hook_ops selinux_nf_ops[] = {
                .hooknum =      NF_INET_LOCAL_OUT,
                .priority =     NF_IP_PRI_SELINUX_FIRST,
        },
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+#if IS_ENABLED(CONFIG_IPV6)
        {
                .hook =         selinux_ipv6_postroute,
                .pf =           NFPROTO_IPV6,