linux-kernel - Re: [PATCH net v2] net: tun: fix bugs for oversize packet when napi frags enabled

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CANn89iKYgg6o5wQQ+QrKUU6jv7FBejU=xg+jxkTVZb_9CCxReg@mail.gmail.com>
Date:   Sat, 29 Oct 2022 08:35:11 -0700
From:   Eric Dumazet <edumazet@...gle.com>
To:     Ziyang Xuan <william.xuanziyang@...wei.com>
Cc:     davem@...emloft.net, kuba@...nel.org, pabeni@...hat.com,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        peterpenkov96@...il.com, maheshb@...gle.com, ast@...nel.org,
        daniel@...earbox.net, hawk@...nel.org, john.fastabend@...il.com
Subject: Re: [PATCH net v2] net: tun: fix bugs for oversize packet when napi
 frags enabled

On Sat, Oct 29, 2022 at 2:41 AM Ziyang Xuan
<william.xuanziyang@...wei.com> wrote:
>
> Recently, we got two syzkaller problems because of oversize packet
> when napi frags enabled.
>
> One of the problems is because the first seg size of the iov_iter
> from user space is very big, it is 2147479538 which is bigger than
> the threshold value for bail out early in __alloc_pages(). And
> skb->pfmemalloc is true, __kmalloc_reserve() would use pfmemalloc
> reserves without __GFP_NOWARN flag. Thus we got a warning as following:
>
>

Reviewed-by: Eric Dumazet <edumazet@...gle.com>