From: valis <sec(a)valis.email> stable inclusion from stable-v5.10.192 commit a8d478200b104ff356f51e1f63499fe46ba8c9b8 category: bugfix issue: #I7ZATX CVE: CVE-2023-4207 Signed-off-by: wanxiaoqing <wanxiaoqing(a)huawei.com> --------------------------------------- [ Upstream commit 76e42ae831991c828cffa8c37736ebfb831ad5ec ] When fw_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free. Fix this by no longer copying the tcf_result struct from the old filter. Fixes: e35a8ee5993b ("net: sched: fw use RCU") Reported-by: valis <sec(a)valis.email> Reported-by: Bing-Jhong Billy Jheng <billy(a)starlabs.sg> Signed-off-by: valis <sec(a)valis.email> Signed-off-by: Jamal Hadi Salim <jhs(a)mojatatu.com> Reviewed-by: Victor Nogueira <victor(a)mojatatu.com> Reviewed-by: Pedro Tammela <pctammela(a)mojatatu.com> Reviewed-by: M A Ramdhan <ramdhan(a)starlabs.sg> Link: https://lore.kernel.org/r/20230729123202.72406-3-jhs@mojatatu.com Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: wanxiaoqing <wanxiaoqing(a)huawei.com> --- net/sched/cls_fw.c | 1 - 1 file changed, 1 deletion(-) diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c index 41f0898a5a56..08c41f1976c4 100644 --- a/net/sched/cls_fw.c +++ b/net/sched/cls_fw.c @@ -266,7 +266,6 @@ static int fw_change(struct net *net, struct sk_buff *in_skb, return -ENOBUFS; fnew->id = f->id; - fnew->res = f->res; fnew->ifindex = f->ifindex; fnew->tp = f->tp; -- 2.25.1