From 9a2cd27dd4bbac47904b0180d3cd713ea39f4adb Mon Sep 17 00:00:00 2001 From: Navid Emamdoost Date: Tue, 10 Mar 2020 20:05:01 +0800 Subject: [PATCH] apparmor: Fix use-after-free in aa_audit_rule_init hulk inclusion category: bugfix bugzilla: NA CVE: CVE-2019-18814 --------------------------- 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 Reviewed-by: Tyler Hicks Signed-off-by: Jason Yan Reviewed-by: Hanjun Guo Signed-off-by: Yang Yingliang --- security/apparmor/audit.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/security/apparmor/audit.c b/security/apparmor/audit.c index eeaddfe0c0fb..70b9730c0be6 100644 --- a/security/apparmor/audit.c +++ b/security/apparmor/audit.c @@ -201,8 +201,9 @@ 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; -- GitLab