[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20240405071531.fv6smp55znlfnul2@joelS2.panther.com>
Date: Fri, 5 Apr 2024 09:15:31 +0200
From: Joel Granados <j.granados@...sung.com>
To: Kuniyuki Iwashima <kuniyu@...zon.com>
CC: <devnull+j.granados.samsung.com@...nel.org>, <Dai.Ngo@...cle.com>,
<alex.aring@...il.com>, <alibuda@...ux.alibaba.com>,
<allison.henderson@...cle.com>, <anna@...nel.org>, <bridge@...ts.linux.dev>,
<chuck.lever@...cle.com>, <coreteam@...filter.org>, <courmisch@...il.com>,
<davem@...emloft.net>, <dccp@...r.kernel.org>, <dhowells@...hat.com>,
<dsahern@...nel.org>, <edumazet@...gle.com>, <fw@...len.de>,
<geliang@...nel.org>, <guwen@...ux.alibaba.com>,
<herbert@...dor.apana.org.au>, <horms@...ge.net.au>, <ja@....bg>,
<jaka@...ux.ibm.com>, <jlayton@...nel.org>, <jmaloy@...hat.com>,
<jreuter@...na.de>, <kadlec@...filter.org>, <keescook@...omium.org>,
<kolga@...app.com>, <kuba@...nel.org>, <linux-afs@...ts.infradead.org>,
<linux-hams@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
<linux-nfs@...r.kernel.org>, <linux-rdma@...r.kernel.org>,
<linux-s390@...r.kernel.org>, <linux-sctp@...r.kernel.org>,
<linux-wpan@...r.kernel.org>, <linux-x25@...r.kernel.org>,
<lucien.xin@...il.com>, <lvs-devel@...r.kernel.org>,
<marc.dionne@...istor.com>, <marcelo.leitner@...il.com>,
<martineau@...nel.org>, <matttbe@...nel.org>, <mcgrof@...nel.org>,
<miquel.raynal@...tlin.com>, <mptcp@...ts.linux.dev>, <ms@....tdt.de>,
<neilb@...e.de>, <netdev@...r.kernel.org>,
<netfilter-devel@...r.kernel.org>, <pabeni@...hat.com>,
<pablo@...filter.org>, <ralf@...ux-mips.org>, <razor@...ckwall.org>,
<rds-devel@....oracle.com>, <roopa@...dia.com>, <stefan@...enfreihafen.org>,
<steffen.klassert@...unet.com>, <tipc-discussion@...ts.sourceforge.net>,
<tom@...pey.com>, <tonylu@...ux.alibaba.com>,
<trond.myklebust@...merspace.com>, <wenjia@...ux.ibm.com>,
<ying.xue@...driver.com>
Subject: Re: [PATCH v2 4/4] ax.25: Remove the now superfluous sentinel
elements from ctl_table array
On Thu, Mar 28, 2024 at 12:49:34PM -0700, Kuniyuki Iwashima wrote:
> From: Joel Granados via B4 Relay <devnull+j.granados.samsung.com@...nel.org>
> Date: Thu, 28 Mar 2024 16:40:05 +0100
> > This commit comes at the tail end of a greater effort to remove the
> > empty elements at the end of the ctl_table arrays (sentinels) which will
> > reduce the overall build time size of the kernel and run time memory
> > bloat by ~64 bytes per sentinel (further information Link :
> > https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)
> >
> > When we remove the sentinel from ax25_param_table a buffer overflow
> > shows its ugly head. The sentinel's data element used to be changed when
> > CONFIG_AX25_DAMA_SLAVE was not defined.
>
> I think it's better to define the relation explicitly between the
> enum and sysctl table by BUILD_BUG_ON() in ax25_register_dev_sysctl()
>
> BUILD_BUG_ON(AX25_MAX_VALUES != ARRAY_SIZE(ax25_param_table));
>
> and guard AX25_VALUES_DS_TIMEOUT with #ifdef CONFIG_AX25_DAMA_SLAVE
> as done for other enum.
When I remove AX25_VALUES_DS_TIMEOUT from the un-guarded build it
complains in net/ax25/ax25_ds_timer.c (ax25_ds_set_timer). Here is the
report https://lore.kernel.org/oe-kbuild-all/202404040301.qzKmVQGB-lkp@intel.com/.
How best to address this? Should we just guard the whole function and do
nothing when not set? like this:
```
void ax25_ds_set_timer(ax25_dev *ax25_dev)
{
#ifdef COFNIG_AX25_DAMA_SLAVE
if (ax25_dev == NULL) ยทยทยท/* paranoia */
return;
ax25_dev->dama.slave_timeout =
msecs_to_jiffies(ax25_dev->values[AX25_VALUES_DS_TIMEOUT]) / 10;
mod_timer(&ax25_dev->dama.slave_timer, jiffies + HZ);
#else
return;
#endif
}
```
I'm not too familiar with this, so pointing me to the "correct" way to
handle this would be helpfull.
Thx in advance.
Best
--
Joel Granados
Download attachment "signature.asc" of type "application/pgp-signature" (660 bytes)
Powered by blists - more mailing lists