1 files changed, 37 insertions, 16 deletions

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index b0be893..62ebf4f 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -837,31 +837,43 @@ static int smack_inode_setxattr(struct dentry *dentry, const char *name,
 				const void *value, size_t size, int flags)
 {
 	struct smk_audit_info ad;
+	struct smack_known *skp;
+	int check_priv = 0;
+	int check_import = 0;
+	int check_star = 0;
 	int rc = 0;
 
+	/*
+	 * Check label validity here so import won't fail in post_setxattr
+	 */
 	if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
 	    strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
-	    strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
-	    strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
-	    strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
-		if (!smack_privileged(CAP_MAC_ADMIN))
-			rc = -EPERM;
-		/*
-		 * check label validity here so import wont fail on
-		 * post_setxattr
-		 */
-		if (size == 0 || size >= SMK_LONGLABEL ||
-		    smk_import(value, size) == NULL)
-			rc = -EINVAL;
+	    strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
+		check_priv = 1;
+		check_import = 1;
+	} else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
+		   strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
+		check_priv = 1;
+		check_import = 1;
+		check_star = 1;
 	} else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
-		if (!smack_privileged(CAP_MAC_ADMIN))
-			rc = -EPERM;
+		check_priv = 1;
 		if (size != TRANS_TRUE_SIZE ||
 		    strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
 			rc = -EINVAL;
 	} else
 		rc = cap_inode_setxattr(dentry, name, value, size, flags);
 
+	if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
+		rc = -EPERM;
+
+	if (rc == 0 && check_import) {
+		skp = smk_import_entry(value, size);
+		if (skp == NULL || (check_star &&
+		    (skp == &smack_known_star || skp == &smack_known_web)))
+			rc = -EINVAL;
+	}
+
 	smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
 	smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
 
@@ -2847,8 +2859,17 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
 			if (rc >= 0)
 				transflag = SMK_INODE_TRANSMUTE;
 		}
-		isp->smk_task = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
-		isp->smk_mmap = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
+		/*
+		 * Don't let the exec or mmap label be "*" or "@".
+		 */
+		skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
+		if (skp == &smack_known_star || skp == &smack_known_web)
+			skp = NULL;
+		isp->smk_task = skp;
+		skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
+		if (skp == &smack_known_star || skp == &smack_known_web)
+			skp = NULL;
+		isp->smk_mmap = skp;
 
 		dput(dp);
 		break;