[PATCH] ima: Defer query for iversion until it is needed

[PATCH] ima: Defer query for iversion until it is needed

[Stefan Berger]

Defer the query for the iversion until it is needed.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
---
 security/integrity/ima/ima_api.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index c1e76282b5ee..4410d45eb281 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -248,7 +248,6 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
 	int result = 0;
 	int length;
 	void *tmpbuf;
-	u64 i_version;
 
 	/*
 	 * Always collect the modsig, because IMA might have already collected
@@ -267,7 +266,6 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
 	 * to an initial measurement/appraisal/audit, but was modified to
 	 * assume the file changed.
 	 */
-	i_version = inode_query_iversion(inode);
 	hash.hdr.algo = algo;
 	hash.hdr.length = hash_digest_size[algo];
 
@@ -304,7 +302,7 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
 
 	iint->ima_hash = tmpbuf;
 	memcpy(iint->ima_hash, &hash, length);
-	iint->version = i_version;
+	iint->version = inode_query_iversion(inode);
 
 	/* Possibly temporary failure due to type of read (eg. O_DIRECT) */
 	if (!result)
-- 
2.36.1

Re: [PATCH] ima: Defer query for iversion until it is needed

[Mimi Zohar]

Hi Stefan,

On Wed, 2022-06-29 at 22:03 -0400, Stefan Berger wrote:
> Defer the query for the iversion until it is needed.
> 
> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
> ---
>  security/integrity/ima/ima_api.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
> index c1e76282b5ee..4410d45eb281 100644
> --- a/security/integrity/ima/ima_api.c
> +++ b/security/integrity/ima/ima_api.c
> @@ -248,7 +248,6 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
>  	int result = 0;
>  	int length;
>  	void *tmpbuf;
> -	u64 i_version;
>  
>  	/*
>  	 * Always collect the modsig, because IMA might have already collected
> @@ -267,7 +266,6 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
>  	 * to an initial measurement/appraisal/audit, but was modified to
>  	 * assume the file changed.
>  	 */
> -	i_version = inode_query_iversion(inode);
>  	hash.hdr.algo = algo;
>  	hash.hdr.length = hash_digest_size[algo];
>  
> @@ -304,7 +302,7 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
>  
>  	iint->ima_hash = tmpbuf;
>  	memcpy(iint->ima_hash, &hash, length);
> -	iint->version = i_version;
> +	iint->version = inode_query_iversion(inode);
>  
>  	/* Possibly temporary failure due to type of read (eg. O_DIRECT) */
>  	if (!result)

Using the i_version value before calculating the file hash was done
intentionally in case the file changed.

thanks,

Mimi