netdev - Re: [PATCH net] ipv4: convert fib_num_tclassid_users to atomic

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]

Date:   Wed, 1 Dec 2021 18:58:05 -0800
From:   Eric Dumazet <edumazet@...gle.com>
To:     David Ahern <dsahern@...il.com>
Cc:     Eric Dumazet <eric.dumazet@...il.com>,
        "David S . Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        netdev <netdev@...r.kernel.org>, David Ahern <dsahern@...nel.org>
Subject: Re: [PATCH net] ipv4: convert fib_num_tclassid_users to atomic_t

On Wed, Dec 1, 2021 at 6:42 PM David Ahern <dsahern@...il.com> wrote:
>
> On 12/1/21 7:26 PM, Eric Dumazet wrote:
> > From: Eric Dumazet <edumazet@...gle.com>
> >
> > Before commit faa041a40b9f ("ipv4: Create cleanup helper for fib_nh")
> > changes to net->ipv4.fib_num_tclassid_users were protected by RTNL.
> >
> > After the change, this is no longer the case, as free_fib_info_rcu()
> > runs after rcu grace period, without rtnl being held.
> >
> > Fixes: faa041a40b9f ("ipv4: Create cleanup helper for fib_nh")
> > Signed-off-by: Eric Dumazet <edumazet@...gle.com>
> > Cc: David Ahern <dsahern@...nel.org>
> > ---
> >  include/net/ip_fib.h     | 2 +-
> >  include/net/netns/ipv4.h | 2 +-
> >  net/ipv4/fib_frontend.c  | 2 +-
> >  net/ipv4/fib_rules.c     | 4 ++--
> >  net/ipv4/fib_semantics.c | 4 ++--
> >  5 files changed, 7 insertions(+), 7 deletions(-)
> >
>
> Thanks, Eric. Was this found by syzbot or code inspection?
>

Code inspection, while plumbing my dev_hold_track() and dev_put_track() helpers.


> Reviewed-by: David Ahern <dsahern@...nel.org>
>
>