This is a note to let you know that I've just added the patch titled
ima: do not update security.ima if appraisal status is not INTEGRITY_PASS
to the 4.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: ima-do-not-update-security.ima-if-appraisal-status-is-not-integrity_pass.patch and it can be found in the queue-4.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From 020aae3ee58c1af0e7ffc4e2cc9fe4dc630338cb Mon Sep 17 00:00:00 2001
From: Roberto Sassu roberto.sassu@huawei.com Date: Tue, 7 Nov 2017 11:37:07 +0100 Subject: ima: do not update security.ima if appraisal status is not INTEGRITY_PASS
From: Roberto Sassu roberto.sassu@huawei.com
commit 020aae3ee58c1af0e7ffc4e2cc9fe4dc630338cb upstream.
Commit b65a9cfc2c38 ("Untangling ima mess, part 2: deal with counters") moved the call of ima_file_check() from may_open() to do_filp_open() at a point where the file descriptor is already opened.
This breaks the assumption made by IMA that file descriptors being closed belong to files whose access was granted by ima_file_check(). The consequence is that security.ima and security.evm are updated with good values, regardless of the current appraisal status.
For example, if a file does not have security.ima, IMA will create it after opening the file for writing, even if access is denied. Access to the file will be allowed afterwards.
Avoid this issue by checking the appraisal status before updating security.ima.
Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Mimi Zohar zohar@linux.vnet.ibm.com Signed-off-by: James Morris james.l.morris@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- security/integrity/ima/ima_appraise.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -320,6 +320,9 @@ void ima_update_xattr(struct integrity_i if (iint->flags & IMA_DIGSIG) return;
+ if (iint->ima_file_status != INTEGRITY_PASS) + return; + rc = ima_collect_measurement(iint, file, NULL, 0, ima_hash_algo); if (rc < 0) return;
Patches currently in stable-queue which might be from roberto.sassu@huawei.com are
queue-4.13/ima-do-not-update-security.ima-if-appraisal-status-is-not-integrity_pass.patch