Re: [PATCH net] ethtool: fix stack overflow in ethnl_parse_bitset()

2020-12-09 Thread Jakub Kicinski
On Tue, 8 Dec 2020 23:13:51 +0100 (CET) Michal Kubecek wrote: > Syzbot reported a stack overflow in bitmap_from_arr32() called from > ethnl_parse_bitset() when bitset from netlink message is longer than > target bitmap length. While ethnl_compact_sanity_checks() makes sure that > trailing part is

[PATCH net] ethtool: fix stack overflow in ethnl_parse_bitset()

2020-12-08 Thread Michal Kubecek
Syzbot reported a stack overflow in bitmap_from_arr32() called from ethnl_parse_bitset() when bitset from netlink message is longer than target bitmap length. While ethnl_compact_sanity_checks() makes sure that trailing part is all zeros (i.e. the request does not try to touch bits kernel does not