From ebfe3c5183733f784264450a41646a482f964e5e Mon Sep 17 00:00:00 2001 From: Di Zhu Date: Wed, 21 Oct 2020 10:00:53 +0800 Subject: rtnetlink: fix data overflow in rtnl_calcit() "ip addr show" command execute error when we have a physical network card with a large number of VFs The return value of if_nlmsg_size() in rtnl_calcit() will exceed range of u16 data type when any network cards has a larger number of VFs. rtnl_vfinfo_size() will significant increase needed dump size when the value of num_vfs is larger. Eventually we get a wrong value of min_ifinfo_dump_size because of overflow which decides the memory size needed by netlink dump and netlink_dump() will return -EMSGSIZE because of not enough memory was allocated. So fix it by promoting min_dump_alloc data type to u32 to avoid whole netlink message size overflow and it's also align with the data type of struct netlink_callback{}.min_dump_alloc which is assigned by return value of rtnl_calcit() Signed-off-by: Di Zhu Link: https://lore.kernel.org/r/20201021020053.1401-1-zhudi21@huawei.com Signed-off-by: Jakub Kicinski --- include/linux/netlink.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 666cd0390699..9f118771e248 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -240,7 +240,7 @@ struct netlink_dump_control { int (*done)(struct netlink_callback *); void *data; struct module *module; - u16 min_dump_alloc; + u32 min_dump_alloc; }; int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb, -- cgit v1.2.3