Re: [PATCH net v1] net: wwan: fix global oob in wwan_rtnl_policy

[Simon Horman]

On Tue, Oct 15, 2024 at 09:16:21PM +0800, Lin Ma wrote:
> The variable wwan_rtnl_link_ops assign a *bigger* maxtype which leads to
> a global out-of-bounds read when parsing the netlink attributes. Exactly
> same bug cause as the oob fixed in commit b33fb5b801c6 ("net: qualcomm:
> rmnet: fix global oob in rmnet_policy").
> 
> ==================================================================
> BUG: KASAN: global-out-of-bounds in validate_nla lib/nlattr.c:388 [inline]
> BUG: KASAN: global-out-of-bounds in __nla_validate_parse+0x19d7/0x29a0 lib/nlattr.c:603
> Read of size 1 at addr ffffffff8b09cb60 by task syz.1.66276/323862

...

> According to the comment of `nla_parse_nested_deprecated`, use correct size
> `IFLA_WWAN_MAX` here to fix this issue.
> 
> Fixes: 88b710532e53 ("wwan: add interface creation support")
> Signed-off-by: Lin Ma <linma@xxxxxxxxxx>

Reviewed-by: Simon Horman <horms@xxxxxxxxxx>