Commit c54d481d authored Oct 21, 2019 by Navid Emamdoost Committed by John Johansen May 21, 2020

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: 52e8c380 ("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>

parent c6b39f07

security/apparmor/audit.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -197,8 +197,9 @@ int aa_audit_rule_init(u32 field, u32 op, char rulestr, void *vrule)
		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;

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