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From 40fea653c0535b0963a20f3768475a21745966a1 Mon Sep 17 00:00:00 2001
From: Julia Denham <jdenham@redhat.com>
Date: Wed, 5 Oct 2022 10:46:32 -0400
Subject: [KPATCH CVE-2022-2588] kpatch fixes for CVE-2022-2588

Kernels:
4.18.0-372.9.1.el8
4.18.0-372.13.1.el8_6
4.18.0-372.16.1.el8_6
4.18.0-372.19.1.el8_6
4.18.0-372.26.1.el8_6


Kpatch-MR: https://gitlab.com/redhat/prdsc/rhel/src/kpatch/rhel-8/-/merge_requests/57
Approved-by: Joe Lawrence (@joe.lawrence)
Approved-by: Yannick Cote (@ycote1)
Changes since last build:
arches: x86_64 ppc64le
cls_route.o: changed function: route4_change
---------------------------

Modifications: none

commit da65135ce599844336767732fe9f4adc731ddf03
Author: Felix Maurer <fmaurer@redhat.com>
Date:   Fri Aug 19 15:28:46 2022 +0200

    net_sched: cls_route: remove from list when handle is 0

    Bugzilla: https://bugzilla.redhat.com/2121817
    CVE: CVE-2022-2588
    Y-Commit: 30cff48f9bf8efc15d8a7294c6bf88f013eed546

    O-Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2116328
    O-CVE: CVE-2022-2588

    commit 9ad36309e2719a884f946678e0296be10f0bb4c1
    Author: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
    Date:   Tue Aug 9 14:05:18 2022 -0300

        net_sched: cls_route: remove from list when handle is 0

        When a route filter is replaced and the old filter has a 0 handle, the old
        one won't be removed from the hashtable, while it will still be freed.

        The test was there since before commit 1109c00547fc ("net: sched: RCU
        cls_route"), when a new filter was not allocated when there was an old one.
        The old filter was reused and the reinserting would only be necessary if an
        old filter was replaced. That was still wrong for the same case where the
        old handle was 0.

        Remove the old filter from the list independently from its handle value.

        This fixes CVE-2022-2588, also reported as ZDI-CAN-17440.

        Reported-by: Zhenpeng Lin <zplin@u.northwestern.edu>
        Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
        Reviewed-by: Kamal Mostafa <kamal@canonical.com>
        Cc: <stable@vger.kernel.org>
        Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
        Link: https://lore.kernel.org/r/20220809170518.164662-1-cascardo@canonical.com
        Signed-off-by: Jakub Kicinski <kuba@kernel.org>

    Signed-off-by: Felix Maurer <fmaurer@redhat.com>
    Signed-off-by: Augusto Caringi <acaringi@redhat.com>

Signed-off-by: Julia Denham <jdenham@redhat.com>
---
 net/sched/cls_route.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
index 94dbc05e40f7..882a0ad65af5 100644
--- a/net/sched/cls_route.c
+++ b/net/sched/cls_route.c
@@ -530,7 +530,7 @@ static int route4_change(struct net *net, struct sk_buff *in_skb,
 	rcu_assign_pointer(f->next, f1);
 	rcu_assign_pointer(*fp, f);
 
-	if (fold && fold->handle && f->handle != fold->handle) {
+	if (fold) {
 		th = to_hash(fold->handle);
 		h = from_hash(fold->handle >> 16);
 		b = rtnl_dereference(head->table[th]);
-- 
2.37.3