[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <2c7a813d-bbbf-4061-b8ad-efa4e7f03d26@linux.dev>
Date: Fri, 13 Oct 2023 09:56:49 +0100
From: Vadim Fedorenko <vadim.fedorenko@...ux.dev>
To: Ma Ke <make_ruc2021@....com>, jmaloy@...hat.com,
ying.xue@...driver.com, davem@...emloft.net, edumazet@...gle.com,
kuba@...nel.org, pabeni@...hat.com
Cc: netdev@...r.kernel.org, tipc-discussion@...ts.sourceforge.net,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH] tipc: Fix uninit-value access in tipc_nl_node_get_link()
On 13/10/2023 08:04, Ma Ke wrote:
> Names must be null-terminated strings. If a name which is not
> null-terminated is passed through netlink, strstr() and similar
> functions can cause buffer overrun. This patch fixes this issue
> by returning -EINVAL if a non-null-terminated name is passed.
>
> Signed-off-by: Ma Ke <make_ruc2021@....com>
> ---
> net/tipc/node.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/net/tipc/node.c b/net/tipc/node.c
> index 3105abe97bb9..a02bcd7e07d3 100644
> --- a/net/tipc/node.c
> +++ b/net/tipc/node.c
> @@ -2519,6 +2519,9 @@ int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
> return -EINVAL;
>
> name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
> + if (name[strnlen(name,
> + nla_len(attrs[TIPC_NLA_LINK_NAME]))] != '\0')
> + return -EINVAL;
The better choice would be to use strncmp() with limit of
TIPC_MAX_LINK_NAME in tipc_node_find_by_name().
This patch fixes tipc_nl_node_get_link(), but the same pattern is used
in tipc_nl_node_set_link() and tipc_nl_node_reset_link_stats(), these
functions also need improvements. Changes to strncmp() and strnstr()
will fix all spots.
>
> msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
> if (!msg.skb)
Powered by blists - more mailing lists