linux-kernel - Re: [PATCH] net: xfrm: fix return value check in ipcomp

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: <20231006114751.GA29258@breakpoint.cc>
Date:   Fri, 6 Oct 2023 13:47:51 +0200
From:   Florian Westphal <fw@...len.de>
To:     Ma Ke <make_ruc2021@....com>
Cc:     steffen.klassert@...unet.com, herbert@...dor.apana.org.au,
        davem@...emloft.net, edumazet@...gle.com, kuba@...nel.org,
        pabeni@...hat.com, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] net: xfrm: fix return value check in ipcomp_compress

Ma Ke <make_ruc2021@....com> wrote:
> In ipcomp_compress, to avoid an unexpected result returned by
> pskb_trim, we should check the return value of pskb_trim().
> 
> Signed-off-by: Ma Ke <make_ruc2021@....com>
> ---
>  net/xfrm/xfrm_ipcomp.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/net/xfrm/xfrm_ipcomp.c b/net/xfrm/xfrm_ipcomp.c
> index 9c0fa0e1786a..5f2e6edadf48 100644
> --- a/net/xfrm/xfrm_ipcomp.c
> +++ b/net/xfrm/xfrm_ipcomp.c
> @@ -144,7 +144,9 @@ static int ipcomp_compress(struct xfrm_state *x, struct sk_buff *skb)
>  	memcpy(start + sizeof(struct ip_comp_hdr), scratch, dlen);
>  	local_bh_enable();
>  
> -	pskb_trim(skb, dlen + sizeof(struct ip_comp_hdr));
> +	err = pskb_trim(skb, dlen + sizeof(struct ip_comp_hdr));
> +	if (unlikely(err))
> +		goto out;

This can't be right, this now calls local_bh_enable() twice.