ima: Shallow copy the args_p member of ima_rule_entry.lsm elements

The args_p member is a simple string that is allocated by
ima_rule_init(). Shallow copy it like other non-LSM references in
ima_rule_entry structs.

There are no longer any necessary error path cleanups to do in
ima_lsm_copy_rule().

Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index cf3ddb3..86ccd00 100644 (file)
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -300,10 +300,13 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry)
                        continue;
 
                nentry->lsm[i].type = entry->lsm[i].type;
-               nentry->lsm[i].args_p = kstrdup(entry->lsm[i].args_p,
-                                               GFP_KERNEL);
-               if (!nentry->lsm[i].args_p)
-                       goto out_err;
+               nentry->lsm[i].args_p = entry->lsm[i].args_p;
+               /*
+                * Remove the reference from entry so that the associated
+                * memory will not be freed during a later call to
+                * ima_lsm_free_rule(entry).
+                */
+               entry->lsm[i].args_p = NULL;
 
                security_filter_rule_init(nentry->lsm[i].type,
                                          Audit_equal,
@@ -311,14 +314,9 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry)
                                          &nentry->lsm[i].rule);
                if (!nentry->lsm[i].rule)
                        pr_warn("rule for LSM \'%s\' is undefined\n",
-                               (char *)entry->lsm[i].args_p);
+                               (char *)nentry->lsm[i].args_p);
        }
        return nentry;
-
-out_err:
-       ima_lsm_free_rule(nentry);
-       kfree(nentry);
-       return NULL;
 }
 
 static int ima_lsm_update_rule(struct ima_rule_entry *entry)