apparmor: fix change_hat not finding hat after policy replacement

After a policy replacement, the task cred may be out of date and need
to be updated. However change_hat is using the stale profiles from
the out of date cred resulting in either: a stale profile being applied
or, incorrect failure when searching for a hat profile as it has been
migrated to the new parent profile.

Fixes: 6228229860a6ed35b8dfc0fc13dfa3daff01213a (failure to find hat)
Fixes: 95c652c046bf3d02e9c070ea38d8ec25a74ad262 (stale policy being applied)
Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1000287
Cc: stable@vger.kernel.org
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index fc3036b34e5128cc73910eb6e3b2bbd2d94d9e50..a4d90aa1045afc46499e00da9baf9bbcea34752a 100644 (file)
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -621,8 +621,8 @@ int aa_change_hat(const char *hats[], int count, u64 token, bool permtest)
        /* released below */
        cred = get_current_cred();
        cxt = cred_cxt(cred);
-       profile = aa_cred_profile(cred);
-       previous_profile = cxt->previous;
+       profile = aa_get_newest_profile(aa_cred_profile(cred));
+       previous_profile = aa_get_newest_profile(cxt->previous);
 
        if (unconfined(profile)) {
                info = "unconfined";
@@ -718,6 +718,8 @@ audit:
 out:
        aa_put_profile(hat);
        kfree(name);
+       aa_put_profile(profile);
+       aa_put_profile(previous_profile);
        put_cred(cred);
 
        return error;