From: Roberto Sassu roberto.sassu@huawei.com
[ Upstream commit 2e3a34e9f409ebe83d1af7cd2f49fca7af97dfac ]
This patch fixes the return value of ima_write_policy() when a new policy is directly passed to IMA and the current policy requires appraisal of the file containing the policy. Currently, if appraisal is not in ENFORCE mode, ima_write_policy() returns 0 and leads user space applications to an endless loop. Fix this issue by denying the operation regardless of the appraisal mode.
Cc: stable@vger.kernel.org # 4.10.x Fixes: 19f8a84713edc ("ima: measure and appraise the IMA policy itself") Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Reviewed-by: Krzysztof Struczynski krzysztof.struczynski@huawei.com Signed-off-by: Mimi Zohar zohar@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- security/integrity/ima/ima_fs.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 2000e8df0301..68571c40d61f 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -340,8 +340,7 @@ static ssize_t ima_write_policy(struct file *file, const char __user *buf, integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL, "policy_update", "signed policy required", 1, 0); - if (ima_appraise & IMA_APPRAISE_ENFORCE) - result = -EACCES; + result = -EACCES; } else { result = ima_parse_add_rule(data); }