apparmor: Fix use-after-free in aa_audit_rule_init
In the implementation of aa_audit_rule_init(), when aa_label_parse()
fails the allocated memory for rule is released using
aa_audit_rule_free(). But after this release, the return statement
tries to access the label field of the rule which results in
use-after-free. Before releasing the rule, copy errNo and return it
after release.
Fixes: 52e8c38001d8 ("apparmor: Fix memory leak of rule on error exit path")
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
diff --git a/security/apparmor/audit.c b/security/apparmor/audit.c
index 5a98661..5977325 100644
--- a/security/apparmor/audit.c
+++ b/security/apparmor/audit.c
@@ -197,8 +197,9 @@
rule->label = aa_label_parse(&root_ns->unconfined->label, rulestr,
GFP_KERNEL, true, false);
if (IS_ERR(rule->label)) {
+ int err = PTR_ERR(rule->label);
aa_audit_rule_free(rule);
- return PTR_ERR(rule->label);
+ return err;
}
*vrule = rule;
