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Diffstat (limited to 'security/integrity/ima/ima_main.c')
-rw-r--r--security/integrity/ima/ima_main.c123
1 files changed, 65 insertions, 58 deletions
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 2917f980bf30..62f59eca32d3 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -77,42 +77,39 @@ __setup("ima_hash=", hash_setup);
* could result in a file measurement error.
*
*/
-static void ima_rdwr_violation_check(struct file *file)
+static void ima_rdwr_violation_check(struct file *file,
+ struct integrity_iint_cache *iint,
+ int must_measure,
+ char **pathbuf,
+ const char **pathname)
{
struct inode *inode = file_inode(file);
fmode_t mode = file->f_mode;
bool send_tomtou = false, send_writers = false;
- char *pathbuf = NULL;
- const char *pathname;
-
- if (!S_ISREG(inode->i_mode) || !ima_initialized)
- return;
if (mode & FMODE_WRITE) {
if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) {
- struct integrity_iint_cache *iint;
- iint = integrity_iint_find(inode);
+ if (!iint)
+ iint = integrity_iint_find(inode);
/* IMA_MEASURE is set from reader side */
if (iint && (iint->flags & IMA_MEASURE))
send_tomtou = true;
}
} else {
- if ((atomic_read(&inode->i_writecount) > 0) &&
- ima_must_measure(inode, MAY_READ, FILE_CHECK))
+ if ((atomic_read(&inode->i_writecount) > 0) && must_measure)
send_writers = true;
}
if (!send_tomtou && !send_writers)
return;
- pathname = ima_d_path(&file->f_path, &pathbuf);
+ *pathname = ima_d_path(&file->f_path, pathbuf);
if (send_tomtou)
- ima_add_violation(file, pathname, "invalid_pcr", "ToMToU");
+ ima_add_violation(file, *pathname, "invalid_pcr", "ToMToU");
if (send_writers)
- ima_add_violation(file, pathname,
+ ima_add_violation(file, *pathname,
"invalid_pcr", "open_writers");
- kfree(pathbuf);
}
static void ima_check_last_writer(struct integrity_iint_cache *iint,
@@ -124,11 +121,13 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint,
return;
mutex_lock(&inode->i_mutex);
- if (atomic_read(&inode->i_writecount) == 1 &&
- iint->version != inode->i_version) {
- iint->flags &= ~IMA_DONE_MASK;
- if (iint->flags & IMA_APPRAISE)
- ima_update_xattr(iint, file);
+ if (atomic_read(&inode->i_writecount) == 1) {
+ if ((iint->version != inode->i_version) ||
+ (iint->flags & IMA_NEW_FILE)) {
+ iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE);
+ if (iint->flags & IMA_APPRAISE)
+ ima_update_xattr(iint, file);
+ }
}
mutex_unlock(&inode->i_mutex);
}
@@ -154,19 +153,20 @@ void ima_file_free(struct file *file)
ima_check_last_writer(iint, inode, file);
}
-static int process_measurement(struct file *file, const char *filename,
- int mask, int function)
+static int process_measurement(struct file *file, int mask, int function,
+ int opened)
{
struct inode *inode = file_inode(file);
- struct integrity_iint_cache *iint;
+ struct integrity_iint_cache *iint = NULL;
struct ima_template_desc *template_desc;
char *pathbuf = NULL;
const char *pathname = NULL;
- int rc = -ENOMEM, action, must_appraise, _func;
+ int rc = -ENOMEM, action, must_appraise;
struct evm_ima_xattr_data *xattr_value = NULL, **xattr_ptr = NULL;
int xattr_len = 0;
+ bool violation_check;
- if (!ima_initialized || !S_ISREG(inode->i_mode))
+ if (!ima_policy_flag || !S_ISREG(inode->i_mode))
return 0;
/* Return an IMA_MEASURE, IMA_APPRAISE, IMA_AUDIT action
@@ -174,19 +174,33 @@ static int process_measurement(struct file *file, const char *filename,
* Included is the appraise submask.
*/
action = ima_get_action(inode, mask, function);
- if (!action)
+ violation_check = ((function == FILE_CHECK || function == MMAP_CHECK) &&
+ (ima_policy_flag & IMA_MEASURE));
+ if (!action && !violation_check)
return 0;
must_appraise = action & IMA_APPRAISE;
/* Is the appraise rule hook specific? */
- _func = (action & IMA_FILE_APPRAISE) ? FILE_CHECK : function;
+ if (action & IMA_FILE_APPRAISE)
+ function = FILE_CHECK;
mutex_lock(&inode->i_mutex);
- iint = integrity_inode_get(inode);
- if (!iint)
- goto out;
+ if (action) {
+ iint = integrity_inode_get(inode);
+ if (!iint)
+ goto out;
+ }
+
+ if (violation_check) {
+ ima_rdwr_violation_check(file, iint, action & IMA_MEASURE,
+ &pathbuf, &pathname);
+ if (!action) {
+ rc = 0;
+ goto out_free;
+ }
+ }
/* Determine if already appraised/measured based on bitmask
* (IMA_MEASURE, IMA_MEASURED, IMA_XXXX_APPRAISE, IMA_XXXX_APPRAISED,
@@ -199,15 +213,13 @@ static int process_measurement(struct file *file, const char *filename,
/* Nothing to do, just return existing appraised status */
if (!action) {
if (must_appraise)
- rc = ima_get_cache_status(iint, _func);
+ rc = ima_get_cache_status(iint, function);
goto out_digsig;
}
template_desc = ima_template_desc_current();
- if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) {
- if (action & IMA_APPRAISE_SUBMASK)
- xattr_ptr = &xattr_value;
- } else
+ if ((action & IMA_APPRAISE_SUBMASK) ||
+ strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) != 0)
xattr_ptr = &xattr_value;
rc = ima_collect_measurement(iint, file, xattr_ptr, &xattr_len);
@@ -217,23 +229,26 @@ static int process_measurement(struct file *file, const char *filename,
goto out_digsig;
}
- pathname = filename ?: ima_d_path(&file->f_path, &pathbuf);
+ if (!pathname) /* ima_rdwr_violation possibly pre-fetched */
+ pathname = ima_d_path(&file->f_path, &pathbuf);
if (action & IMA_MEASURE)
ima_store_measurement(iint, file, pathname,
xattr_value, xattr_len);
if (action & IMA_APPRAISE_SUBMASK)
- rc = ima_appraise_measurement(_func, iint, file, pathname,
- xattr_value, xattr_len);
+ rc = ima_appraise_measurement(function, iint, file, pathname,
+ xattr_value, xattr_len, opened);
if (action & IMA_AUDIT)
ima_audit_measurement(iint, pathname);
- kfree(pathbuf);
+
out_digsig:
if ((mask & MAY_WRITE) && (iint->flags & IMA_DIGSIG))
rc = -EACCES;
+ kfree(xattr_value);
+out_free:
+ kfree(pathbuf);
out:
mutex_unlock(&inode->i_mutex);
- kfree(xattr_value);
if ((rc && must_appraise) && (ima_appraise & IMA_APPRAISE_ENFORCE))
return -EACCES;
return 0;
@@ -253,7 +268,7 @@ out:
int ima_file_mmap(struct file *file, unsigned long prot)
{
if (file && (prot & PROT_EXEC))
- return process_measurement(file, NULL, MAY_EXEC, MMAP_CHECK);
+ return process_measurement(file, MAY_EXEC, MMAP_CHECK, 0);
return 0;
}
@@ -272,10 +287,7 @@ int ima_file_mmap(struct file *file, unsigned long prot)
*/
int ima_bprm_check(struct linux_binprm *bprm)
{
- return process_measurement(bprm->file,
- (strcmp(bprm->filename, bprm->interp) == 0) ?
- bprm->filename : bprm->interp,
- MAY_EXEC, BPRM_CHECK);
+ return process_measurement(bprm->file, MAY_EXEC, BPRM_CHECK, 0);
}
/**
@@ -288,12 +300,11 @@ int ima_bprm_check(struct linux_binprm *bprm)
* 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 ima_file_check(struct file *file, int mask, int opened)
{
- ima_rdwr_violation_check(file);
- return process_measurement(file, NULL,
+ return process_measurement(file,
mask & (MAY_READ | MAY_WRITE | MAY_EXEC),
- FILE_CHECK);
+ FILE_CHECK, opened);
}
EXPORT_SYMBOL_GPL(ima_file_check);
@@ -316,7 +327,7 @@ int ima_module_check(struct file *file)
#endif
return 0; /* We rely on module signature checking */
}
- return process_measurement(file, NULL, MAY_EXEC, MODULE_CHECK);
+ return process_measurement(file, MAY_EXEC, MODULE_CHECK, 0);
}
int ima_fw_from_file(struct file *file, char *buf, size_t size)
@@ -327,7 +338,7 @@ int ima_fw_from_file(struct file *file, char *buf, size_t size)
return -EACCES; /* INTEGRITY_UNKNOWN */
return 0;
}
- return process_measurement(file, NULL, MAY_EXEC, FIRMWARE_CHECK);
+ return process_measurement(file, MAY_EXEC, FIRMWARE_CHECK, 0);
}
static int __init init_ima(void)
@@ -336,14 +347,10 @@ static int __init init_ima(void)
hash_setup(CONFIG_IMA_DEFAULT_HASH);
error = ima_init();
- if (error)
- goto out;
-
- error = ima_init_keyring(INTEGRITY_KEYRING_IMA);
- if (error)
- goto out;
- ima_initialized = 1;
-out:
+ if (!error) {
+ ima_initialized = 1;
+ ima_update_policy_flag();
+ }
return error;
}