[v1] evm: call dump_security_xattr() in all cases to remove code duplication

[PATCH -next] evm: call dump_security_xattr() in all cases to remove code duplication

Posted by Xiu Jianfeng 2 years, 7 months ago

Currently dump_security_xattr() is used to dump security xattr value
which is larger than 64 bytes, otherwise, pr_debug() is used. In order
to remove code duplication, refator dump_security_xattr() and call it in
all cases.

Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
---
 security/integrity/evm/evm_crypto.c | 33 ++++++++++++++---------------
 1 file changed, 16 insertions(+), 17 deletions(-)

diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
index fa5ff13fa8c9..0fe6c9cd8eab 100644
--- a/security/integrity/evm/evm_crypto.c
+++ b/security/integrity/evm/evm_crypto.c
@@ -183,8 +183,8 @@ static void hmac_add_misc(struct shash_desc *desc, struct inode *inode,
  * Dump large security xattr values as a continuous ascii hexademical string.
  * (pr_debug is limited to 64 bytes.)
  */
-static void dump_security_xattr(const char *prefix, const void *src,
-				size_t count)
+static void dump_security_xattr_l(const char *prefix, const void *src,
+				  size_t count)
 {
 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
 	char *asciihex, *p;
@@ -200,6 +200,16 @@ static void dump_security_xattr(const char *prefix, const void *src,
 #endif
 }
 
+static void dump_security_xattr(const char *name, const char *value,
+				size_t value_len)
+{
+	if (value_len < 64)
+		pr_debug("%s: (%zu) [%*phN]\n", name, value_len,
+			 (int)value_len, value);
+	else
+		dump_security_xattr_l(name, value, value_len);
+}
+
 /*
  * Calculate the HMAC value across the set of protected security xattrs.
  *
@@ -254,15 +264,9 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry,
 			if (is_ima)
 				ima_present = true;
 
-			if (req_xattr_value_len < 64)
-				pr_debug("%s: (%zu) [%*phN]\n", req_xattr_name,
-					 req_xattr_value_len,
-					 (int)req_xattr_value_len,
-					 req_xattr_value);
-			else
-				dump_security_xattr(req_xattr_name,
-						    req_xattr_value,
-						    req_xattr_value_len);
+			dump_security_xattr(req_xattr_name,
+					    req_xattr_value,
+					    req_xattr_value_len);
 			continue;
 		}
 		size = vfs_getxattr_alloc(&init_user_ns, dentry, xattr->name,
@@ -286,12 +290,7 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry,
 		if (is_ima)
 			ima_present = true;
 
-		if (xattr_size < 64)
-			pr_debug("%s: (%zu) [%*phN]", xattr->name, xattr_size,
-				 (int)xattr_size, xattr_value);
-		else
-			dump_security_xattr(xattr->name, xattr_value,
-					    xattr_size);
+		dump_security_xattr(xattr->name, xattr_value, xattr_size);
 	}
 	hmac_add_misc(desc, inode, type, data->digest);
 
-- 
2.17.1

Re: [PATCH -next] evm: call dump_security_xattr() in all cases to remove code duplication

Posted by xiujianfeng 2 years, 7 months ago

sorry, I forget to add v2 tag, this is based on commit b8dc57947379
("ima: fix ima_delete_rules() kernel-doc warning").

On 2023/1/31 10:00, Xiu Jianfeng wrote:
> Currently dump_security_xattr() is used to dump security xattr value
> which is larger than 64 bytes, otherwise, pr_debug() is used. In order
> to remove code duplication, refator dump_security_xattr() and call it in
> all cases.
> 
> Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
> ---
>  security/integrity/evm/evm_crypto.c | 33 ++++++++++++++---------------
>  1 file changed, 16 insertions(+), 17 deletions(-)
> 
> diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
> index fa5ff13fa8c9..0fe6c9cd8eab 100644
> --- a/security/integrity/evm/evm_crypto.c
> +++ b/security/integrity/evm/evm_crypto.c
> @@ -183,8 +183,8 @@ static void hmac_add_misc(struct shash_desc *desc, struct inode *inode,
>   * Dump large security xattr values as a continuous ascii hexademical string.
>   * (pr_debug is limited to 64 bytes.)
>   */
> -static void dump_security_xattr(const char *prefix, const void *src,
> -				size_t count)
> +static void dump_security_xattr_l(const char *prefix, const void *src,
> +				  size_t count)
>  {
>  #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
>  	char *asciihex, *p;
> @@ -200,6 +200,16 @@ static void dump_security_xattr(const char *prefix, const void *src,
>  #endif
>  }
>  
> +static void dump_security_xattr(const char *name, const char *value,
> +				size_t value_len)
> +{
> +	if (value_len < 64)
> +		pr_debug("%s: (%zu) [%*phN]\n", name, value_len,
> +			 (int)value_len, value);
> +	else
> +		dump_security_xattr_l(name, value, value_len);
> +}
> +
>  /*
>   * Calculate the HMAC value across the set of protected security xattrs.
>   *
> @@ -254,15 +264,9 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry,
>  			if (is_ima)
>  				ima_present = true;
>  
> -			if (req_xattr_value_len < 64)
> -				pr_debug("%s: (%zu) [%*phN]\n", req_xattr_name,
> -					 req_xattr_value_len,
> -					 (int)req_xattr_value_len,
> -					 req_xattr_value);
> -			else
> -				dump_security_xattr(req_xattr_name,
> -						    req_xattr_value,
> -						    req_xattr_value_len);
> +			dump_security_xattr(req_xattr_name,
> +					    req_xattr_value,
> +					    req_xattr_value_len);
>  			continue;
>  		}
>  		size = vfs_getxattr_alloc(&init_user_ns, dentry, xattr->name,
> @@ -286,12 +290,7 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry,
>  		if (is_ima)
>  			ima_present = true;
>  
> -		if (xattr_size < 64)
> -			pr_debug("%s: (%zu) [%*phN]", xattr->name, xattr_size,
> -				 (int)xattr_size, xattr_value);
> -		else
> -			dump_security_xattr(xattr->name, xattr_value,
> -					    xattr_size);
> +		dump_security_xattr(xattr->name, xattr_value, xattr_size);
>  	}
>  	hmac_add_misc(desc, inode, type, data->digest);
>