[2/4] evm: reset status in evm_inode_post_setattr()
diff mbox series

Message ID 20190516161257.6640-2-roberto.sassu@huawei.com
State New
Headers show
Series
  • [1/4] evm: check hash algorithm passed to init_desc()
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Commit Message

Roberto Sassu May 16, 2019, 4:12 p.m. UTC
This patch adds a call to evm_reset_status() in evm_inode_post_setattr(),
before security.evm is updated. The same is done in the other
evm_inode_post_* functions.

Fixes: 523b74b16bcbb ("evm: reset EVM status when file attributes change")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org
---
 security/integrity/evm/evm_main.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Comments

Mimi Zohar May 20, 2019, 9:19 p.m. UTC | #1
On Thu, 2019-05-16 at 18:12 +0200, Roberto Sassu wrote:
> This patch adds a call to evm_reset_status() in evm_inode_post_setattr(),
> before security.evm is updated. The same is done in the other
> evm_inode_post_* functions.
> 
> Fixes: 523b74b16bcbb ("evm: reset EVM status when file attributes change")
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> Cc: stable@vger.kernel.org

Why all of a sudden do we also need to clear the EVM cached status
when modifying the file attributes?  The HMAC is being recalculated.  
If the reason is because of EVM portable and immutable signatures,
then the "Fixes" tag is incorrect.

Mimi

> ---
>  security/integrity/evm/evm_main.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
> index b6d9f14bc234..b41c2d8a8834 100644
> --- a/security/integrity/evm/evm_main.c
> +++ b/security/integrity/evm/evm_main.c
> @@ -512,8 +512,11 @@ void evm_inode_post_setattr(struct dentry *dentry, int ia_valid)
>  	if (!evm_key_loaded())
>  		return;
>  
> -	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID))
> +	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)) {
> +		evm_reset_status(dentry->d_inode);
> +
>  		evm_update_evmxattr(dentry, NULL, NULL, 0);
> +	}
>  }
>  
>  /*

Patch
diff mbox series

diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index b6d9f14bc234..b41c2d8a8834 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -512,8 +512,11 @@  void evm_inode_post_setattr(struct dentry *dentry, int ia_valid)
 	if (!evm_key_loaded())
 		return;
 
-	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID))
+	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)) {
+		evm_reset_status(dentry->d_inode);
+
 		evm_update_evmxattr(dentry, NULL, NULL, 0);
+	}
 }
 
 /*