netdev - Re: [PATCH RESEND v2 net-next 05/14] ipv6: Move nexthop_find_by_id() after fib6_info

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: <f27f9cd5-6823-4aa8-90c8-5c24c9d30a8d@redhat.com>
Date: Wed, 16 Apr 2025 11:13:38 +0200
From: Paolo Abeni <pabeni@...hat.com>
To: Kuniyuki Iwashima <kuniyu@...zon.com>,
 "David S. Miller" <davem@...emloft.net>, David Ahern <dsahern@...nel.org>,
 Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>
Cc: Simon Horman <horms@...nel.org>, Kuniyuki Iwashima <kuni1840@...il.com>,
 netdev@...r.kernel.org
Subject: Re: [PATCH RESEND v2 net-next 05/14] ipv6: Move nexthop_find_by_id()
 after fib6_info_alloc().

On 4/14/25 8:14 PM, Kuniyuki Iwashima wrote:
> We will get rid of RTNL from RTM_NEWROUTE and SIOCADDRT.
> 
> Then, we must perform two lookups for nexthop and dev under RCU
> to guarantee their lifetime.
> 
> ip6_route_info_create() calls nexthop_find_by_id() first if
> RTA_NH_ID is specified, and then allocates struct fib6_info.
> 
> nexthop_find_by_id() must be called under RCU, but we do not want
> to use GFP_ATOMIC for memory allocation here, which will be likely
> to fail in ip6_route_multipath_add().
> 
> Let's move nexthop_find_by_id() after the memory allocation so
> that we can later split ip6_route_info_create() into two parts:
> the sleepable part and the RCU part.
> 
> Signed-off-by: Kuniyuki Iwashima <kuniyu@...zon.com>

Acked-by: Paolo Abeni <pabeni@...hat.com>