---

yaml --- r: 329109 b: refs/heads/master c: 42c6333 h: refs/heads/master i: 329107: 1f0e9e7 v: v3
git-mirror · Sep 7, 2012 · 59878c7 · 59878c7
1 parent 2831f1a
commit 59878c7
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Showing 4 changed files with 81 additions and 1 deletion.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9957a5043e7b0b7361cdf48eea22b2900293e63a
+refs/heads/master: 42c63330f2b05aa6077c1bfc2798c04afe54f6b2
diff --git a/trunk/include/linux/ima.h b/trunk/include/linux/ima.h
@@ -44,10 +44,27 @@ static inline int ima_file_mmap(struct file *file, unsigned long prot)
 
 #ifdef CONFIG_IMA_APPRAISE
 extern void ima_inode_post_setattr(struct dentry *dentry);
+extern int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
+		       const void *xattr_value, size_t xattr_value_len);
+extern int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name);
 #else
 static inline void ima_inode_post_setattr(struct dentry *dentry)
 {
 	return;
 }
+
+static inline int ima_inode_setxattr(struct dentry *dentry,
+				     const char *xattr_name,
+				     const void *xattr_value,
+				     size_t xattr_value_len)
+{
+	return 0;
+}
+
+static inline int ima_inode_removexattr(struct dentry *dentry,
+					const char *xattr_name)
+{
+	return 0;
+}
 #endif /* CONFIG_IMA_APPRAISE_H */
 #endif /* _LINUX_IMA_H */
diff --git a/trunk/security/integrity/ima/ima_appraise.c b/trunk/security/integrity/ima/ima_appraise.c
@@ -169,3 +169,60 @@ void ima_inode_post_setattr(struct dentry *dentry)
 		rc = inode->i_op->removexattr(dentry, XATTR_NAME_IMA);
 	return;
 }
+
+/*
+ * ima_protect_xattr - protect 'security.ima'
+ *
+ * Ensure that not just anyone can modify or remove 'security.ima'.
+ */
+static int ima_protect_xattr(struct dentry *dentry, const char *xattr_name,
+			     const void *xattr_value, size_t xattr_value_len)
+{
+	if (strcmp(xattr_name, XATTR_NAME_IMA) == 0) {
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+		return 1;
+	}
+	return 0;
+}
+
+static void ima_reset_appraise_flags(struct inode *inode)
+{
+	struct integrity_iint_cache *iint;
+
+	if (!ima_initialized || !ima_appraise || !S_ISREG(inode->i_mode))
+		return;
+
+	iint = integrity_iint_find(inode);
+	if (!iint)
+		return;
+
+	iint->flags &= ~(IMA_COLLECTED | IMA_APPRAISED | IMA_MEASURED);
+	return;
+}
+
+int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
+		       const void *xattr_value, size_t xattr_value_len)
+{
+	int result;
+
+	result = ima_protect_xattr(dentry, xattr_name, xattr_value,
+				   xattr_value_len);
+	if (result == 1) {
+		ima_reset_appraise_flags(dentry->d_inode);
+		result = 0;
+	}
+	return result;
+}
+
+int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name)
+{
+	int result;
+
+	result = ima_protect_xattr(dentry, xattr_name, NULL, 0);
+	if (result == 1) {
+		ima_reset_appraise_flags(dentry->d_inode);
+		result = 0;
+	}
+	return result;
+}
diff --git a/trunk/security/security.c b/trunk/security/security.c
@@ -571,6 +571,9 @@ int security_inode_setxattr(struct dentry *dentry, const char *name,
 	if (unlikely(IS_PRIVATE(dentry->d_inode)))
 		return 0;
 	ret = security_ops->inode_setxattr(dentry, name, value, size, flags);
+	if (ret)
+		return ret;
+	ret = ima_inode_setxattr(dentry, name, value, size);
 	if (ret)
 		return ret;
 	return evm_inode_setxattr(dentry, name, value, size);
@@ -606,6 +609,9 @@ int security_inode_removexattr(struct dentry *dentry, const char *name)
 	if (unlikely(IS_PRIVATE(dentry->d_inode)))
 		return 0;
 	ret = security_ops->inode_removexattr(dentry, name);
+	if (ret)
+		return ret;
+	ret = ima_inode_removexattr(dentry, name);
 	if (ret)
 		return ret;
 	return evm_inode_removexattr(dentry, name);