From 750943a30714b7e9a5a2b0e08eeef7a808b5a869 Mon Sep 17 00:00:00 2001
From: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Date: Thu, 27 Sep 2012 15:57:10 +0300
Subject: [PATCH] ima: remove enforce checking duplication
Based on the IMA appraisal policy, files are appraised. For those
files appraised, the IMA hooks return the integrity appraisal result,
assuming IMA-appraisal is in enforcing mode. This patch combines
both of these criteria (in policy and enforcing file integrity),
removing the checking duplication.
Changelog v1:
- Update hook comments
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
---
security/integrity/ima/ima_main.c | 52 ++++++++++++-------------------
1 file changed, 20 insertions(+), 32 deletions(-)
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 45de18e9a6f22..1cd4eb2c3b907 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -208,7 +208,9 @@ static int process_measurement(struct file *file, const unsigned char *filename,
kfree(pathbuf);
out:
mutex_unlock(&inode->i_mutex);
- return (rc && must_appraise) ? -EACCES : 0;
+ if ((rc && must_appraise) && (ima_appraise & IMA_APPRAISE_ENFORCE))
+ return -EACCES;
+ return 0;
}
/**
@@ -219,19 +221,15 @@ static int process_measurement(struct file *file, const unsigned char *filename,
* Measure files being mmapped executable based on the ima_must_measure()
* policy decision.
*
- * Return 0 on success, an error code on failure.
- * (Based on the results of appraise_measurement().)
+ * On success return 0. On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
*/
int ima_file_mmap(struct file *file, unsigned long prot)
{
- int rc = 0;
-
- if (!file)
- return 0;
- if (prot & PROT_EXEC)
- rc = process_measurement(file, file->f_dentry->d_name.name,
- MAY_EXEC, FILE_MMAP);
- return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
+ if (file && (prot & PROT_EXEC))
+ return process_measurement(file, file->f_dentry->d_name.name,
+ MAY_EXEC, FILE_MMAP);
+ return 0;
}
/**
@@ -244,18 +242,15 @@ int ima_file_mmap(struct file *file, unsigned long prot)
* So we can be certain that what we verify and measure here is actually
* what is being executed.
*
- * Return 0 on success, an error code on failure.
- * (Based on the results of appraise_measurement().)
+ * On success return 0. On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
*/
int ima_bprm_check(struct linux_binprm *bprm)
{
- int rc;
-
- rc = process_measurement(bprm->file,
+ return process_measurement(bprm->file,
(strcmp(bprm->filename, bprm->interp) == 0) ?
bprm->filename : bprm->interp,
MAY_EXEC, BPRM_CHECK);
- return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
}
/**
@@ -265,18 +260,15 @@ int ima_bprm_check(struct linux_binprm *bprm)
*
* Measure files based on the ima_must_measure() policy decision.
*
- * Always return 0 and audit dentry_open failures.
- * (Return code will be based upon measurement appraisal.)
+ * On success return 0. On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
*/
int ima_file_check(struct file *file, int mask)
{
- int rc;
-
ima_rdwr_violation_check(file);
- rc = process_measurement(file, file->f_dentry->d_name.name,
+ return process_measurement(file, file->f_dentry->d_name.name,
mask & (MAY_READ | MAY_WRITE | MAY_EXEC),
FILE_CHECK);
- return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
}
EXPORT_SYMBOL_GPL(ima_file_check);
@@ -286,19 +278,15 @@ EXPORT_SYMBOL_GPL(ima_file_check);
*
* Measure/appraise kernel modules based on policy.
*
- * Always return 0 and audit dentry_open failures.
- * Return code is based upon measurement appraisal.
+ * On success return 0. On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
*/
int ima_module_check(struct file *file)
{
- int rc;
-
if (!file)
- rc = INTEGRITY_UNKNOWN;
- else
- rc = process_measurement(file, file->f_dentry->d_name.name,
- MAY_EXEC, MODULE_CHECK);
- return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
+ return -EACCES; /* INTEGRITY_UNKNOWN */
+ return process_measurement(file, file->f_dentry->d_name.name,
+ MAY_EXEC, MODULE_CHECK);
}
static int __init init_ima(void)
--
GitLab