Revert "ima: limit file hash setting by user to fix and log modes"
authorMimi Zohar <zohar@linux.vnet.ibm.com>
Wed, 2 Nov 2016 13:14:16 +0000 (09:14 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 6 Jun 2018 14:44:33 +0000 (16:44 +0200)
commit f5acb3dcba1ffb7f0b8cbb9dba61500eea5d610b upstream.

Userspace applications have been modified to write security xattrs,
but they are not context aware.  In the case of security.ima, the
security xattr can be either a file hash or a file signature.
Permitting writing one, but not the other requires the application to
be context aware.

In addition, userspace applications might write files to a staging
area, which might not be in policy, and then change some file metadata
(eg. owner) making it in policy.  As a result, these files are not
labeled properly.

This reverts commit c68ed80c97d9720f51ef31fe91560fdd1e121533, which
prevents writing file hashes as security.ima xattrs.

Requested-by: Patrick Ohly <patrick.ohly@intel.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
security/integrity/ima/ima_appraise.c

index 7bf8b00..1e6f23f 100644 (file)
@@ -389,14 +389,10 @@ int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
        result = ima_protect_xattr(dentry, xattr_name, xattr_value,
                                   xattr_value_len);
        if (result == 1) {
-               bool digsig;
-
                if (!xattr_value_len || (xvalue->type >= IMA_XATTR_LAST))
                        return -EINVAL;
-               digsig = (xvalue->type == EVM_IMA_XATTR_DIGSIG);
-               if (!digsig && (ima_appraise & IMA_APPRAISE_ENFORCE))
-                       return -EPERM;
-               ima_reset_appraise_flags(d_backing_inode(dentry), digsig);
+               ima_reset_appraise_flags(d_backing_inode(dentry),
+                        (xvalue->type == EVM_IMA_XATTR_DIGSIG) ? 1 : 0);
                result = 0;
        }
        return result;