netdev - Re: [PATCH bpf] xdp: Reset prog in dev_change_xdp

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:   Sun, 12 Apr 2020 11:11:46 -0700
From:   Jakub Kicinski <kuba@...nel.org>
To:     David Ahern <dsahern@...nel.org>
Cc:     daniel@...earbox.net, ast@...nel.org, netdev@...r.kernel.org,
        David Ahern <dsahern@...il.com>,
        Toke Høiland-Jørgensen <toke@...hat.com>
Subject: Re: [PATCH bpf] xdp: Reset prog in dev_change_xdp_fd when fd is
 negative

On Sun, 12 Apr 2020 07:32:04 -0600 David Ahern wrote:
> From: David Ahern <dsahern@...il.com>
> 
> The commit mentioned in the Fixes tag reuses the local prog variable
> when looking up an expected_fd. The variable is not reset when fd < 0
> causing a detach with the expected_fd set to actually call
> dev_xdp_install for the existing program. The end result is that the
> detach does not happen.
> 
> Fixes: 92234c8f15c8 ("xdp: Support specifying expected existing program when attaching XDP")
> Signed-off-by: David Ahern <dsahern@...il.com>
> Cc: Toke Høiland-Jørgensen <toke@...hat.com>

Reviewed-by: Jakub Kicinski <kuba@...nel.org>