evm: don't copy up 'security.evm' xattr

The security.evm HMAC and the original file signatures contain
filesystem specific data.  As a result, the HMAC and signature
are not the same on the stacked and backing filesystems.

Don't copy up 'security.evm'.

Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
This commit is contained in:
Mimi Zohar
2023-12-12 06:12:43 -05:00
parent 4e8daa7927
commit 40ca4ee313
3 changed files with 14 additions and 1 deletions

View File

@@ -863,6 +863,13 @@ void evm_inode_post_setattr(struct dentry *dentry, int ia_valid)
evm_update_evmxattr(dentry, NULL, NULL, 0);
}
int evm_inode_copy_up_xattr(const char *name)
{
if (strcmp(name, XATTR_NAME_EVM) == 0)
return 1; /* Discard */
return -EOPNOTSUPP;
}
/*
* evm_inode_init_security - initializes security.evm HMAC value
*/