netdev - Re: [PATCH iproute2-next v3 5/8] veth,vxcan: Save/reinitialize/restore whole @struct ifinfomsg

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: <21860aaf-41a1-4a40-2f5f-01fc5ae033ea@gmail.com>
Date:   Sun, 25 Feb 2018 20:28:14 -0700
From:   David Ahern <dsahern@...il.com>
To:     Serhey Popovych <serhe.popovych@...il.com>, netdev@...r.kernel.org
Subject: Re: [PATCH iproute2-next v3 5/8] veth,vxcan:
 Save/reinitialize/restore whole @struct ifinfomsg

On 2/22/18 6:02 AM, Serhey Popovych wrote:
> Now in iplink_parse() we use ->ifi_change and ->ifi_flags fields and
> plan to use ->ifi_index with upcoming change.
> 
> Saving, restoring and reinitializing individual fields is error prone:
> using new field in iplink_parse() without updating callers in veth and
> vxcan will overwrite main device ifinfomsg data.
> 
> Since @struct ifinfomsg is small enough with known sizeof() compiler may
> inline memcpy()/memset() with few load/store instructions.
> 
> Signed-off-by: Serhey Popovych <serhe.popovych@...il.com>
> ---
>  ip/iplink_vxcan.c |   22 ++++++++--------------
>  ip/link_veth.c    |   22 ++++++++--------------
>  2 files changed, 16 insertions(+), 28 deletions(-)

I don't agree that this change has any benefit. Only the flags and
change field are wanted; there is no need to save the entire struct,