diff options
| author | valis <sec@valis.email> | 2023-07-29 08:32:01 -0400 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-07-31 20:10:36 -0700 |
| commit | 76e42ae831991c828cffa8c37736ebfb831ad5ec (patch) | |
| tree | a4063cc30b4cb2f170728aa91a793d58e49e35d3 | |
| parent | 3044b16e7c6fe5d24b1cdbcf1bd0a9d92d1ebd81 (diff) | |
| download | kvm-s390-vfio-76e42ae831991c828cffa8c37736ebfb831ad5ec.tar.gz | |
net/sched: cls_fw: No longer copy tcf_result on update to avoid use-after-free
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@valis.email>
Reported-by: Bing-Jhong Billy Jheng <billy@starlabs.sg>
Signed-off-by: valis <sec@valis.email>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Reviewed-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: M A Ramdhan <ramdhan@starlabs.sg>
Link: https://lore.kernel.org/r/20230729123202.72406-3-jhs@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/sched/cls_fw.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c index 8641f805931793..c49d6af0e04807 100644 --- a/net/sched/cls_fw.c +++ b/net/sched/cls_fw.c @@ -267,7 +267,6 @@ 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; |