| 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
| ||
|
Message-ID: <20221125104401.0e18979f@hermes.local>
Date: Fri, 25 Nov 2022 10:44:01 -0800
From: Stephen Hemminger <stephen@...workplumber.org>
To: Maciej Fijalkowski <maciej.fijalkowski@...el.com>
Cc: Vladimir Oltean <vladimir.oltean@....com>,
<netdev@...r.kernel.org>, "David S. Miller" <davem@...emloft.net>,
"Eric Dumazet" <edumazet@...gle.com>,
Jakub Kicinski <kuba@...nel.org>,
Paolo Abeni <pabeni@...hat.com>,
Claudiu Manoil <claudiu.manoil@....com>,
"Giuseppe Cavallaro" <peppe.cavallaro@...com>,
Alexandre Torgue <alexandre.torgue@...s.st.com>,
Jose Abreu <joabreu@...opsys.com>,
"Maxime Coquelin" <mcoquelin.stm32@...il.com>,
Yang Yang <yang.yang29@....com>,
"Xu Panda" <xu.panda@....com.cn>,
<linux-stm32@...md-mailman.stormreply.com>,
<linux-arm-kernel@...ts.infradead.org>,
<linux-kernel@...r.kernel.org>
Subject: Re: [PATCH net-next] Revert "net: stmmac: use sysfs_streq() instead
of strncmp()"
On Fri, 25 Nov 2022 12:58:23 +0100
Maciej Fijalkowski <maciej.fijalkowski@...el.com> wrote:
> On Fri, Nov 25, 2022 at 12:53:04PM +0200, Vladimir Oltean wrote:
> > This reverts commit f72cd76b05ea1ce9258484e8127932d0ea928f22.
> > This patch is so broken, it hurts. Apparently no one reviewed it and it
> > passed the build testing (because the code was compiled out), but it was
> > obviously never compile-tested, since it produces the following build
> > error, due to an incomplete conversion where an extra argument was left,
> > although the function being called was left:
> >
> > stmmac_main.c: In function ‘stmmac_cmdline_opt’:
> > stmmac_main.c:7586:28: error: too many arguments to function ‘sysfs_streq’
> > 7586 | } else if (sysfs_streq(opt, "pause:", 6)) {
> > | ^~~~~~~~~~~
> > In file included from ../include/linux/bitmap.h:11,
> > from ../include/linux/cpumask.h:12,
> > from ../include/linux/smp.h:13,
> > from ../include/linux/lockdep.h:14,
> > from ../include/linux/mutex.h:17,
> > from ../include/linux/notifier.h:14,
> > from ../include/linux/clk.h:14,
> > from ../drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:17:
> > ../include/linux/string.h:185:13: note: declared here
> > 185 | extern bool sysfs_streq(const char *s1, const char *s2);
> > | ^~~~~~~~~~~
> >
> > What's even worse is that the patch is flat out wrong. The stmmac_cmdline_opt()
> > function does not parse sysfs input, but cmdline input such as
> > "stmmaceth=tc:1,pause:1". The pattern of using strsep() followed by
> > strncmp() for such strings is not unique to stmmac, it can also be found
> > mainly in drivers under drivers/video/fbdev/.
> >
> > With strncmp("tc:", 3), the code matches on the "tc:1" token properly.
> > With sysfs_streq("tc:"), it doesn't.
> >
> > Fixes: f72cd76b05ea ("net: stmmac: use sysfs_streq() instead of strncmp()")
> > Signed-off-by: Vladimir Oltean <vladimir.oltean@....com>
>
> Ah the infamous string handling in C...
>
> Acked-by: Maciej Fijalkowski <maciej.fijalkowski@...el.com>
>
> Even when there would be no build error I agree that we should have kept
> the code as it was.
>
> > ---
> > .../net/ethernet/stmicro/stmmac/stmmac_main.c | 18 +++++++++---------
> > 1 file changed, 9 insertions(+), 9 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > index 1a86e66e4560..3affb7d3a005 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > @@ -7565,31 +7565,31 @@ static int __init stmmac_cmdline_opt(char *str)
> > if (!str || !*str)
> > return 1;
> > while ((opt = strsep(&str, ",")) != NULL) {
> > - if (sysfs_streq(opt, "debug:")) {
> > + if (!strncmp(opt, "debug:", 6)) {
> > if (kstrtoint(opt + 6, 0, &debug))
> > goto err;
> > - } else if (sysfs_streq(opt, "phyaddr:")) {
> > + } else if (!strncmp(opt, "phyaddr:", 8)) {
> > if (kstrtoint(opt + 8, 0, &phyaddr))
> > goto err;
> > - } else if (sysfs_streq(opt, "buf_sz:")) {
> > + } else if (!strncmp(opt, "buf_sz:", 7)) {
> > if (kstrtoint(opt + 7, 0, &buf_sz))
> > goto err;
> > - } else if (sysfs_streq(opt, "tc:")) {
> > + } else if (!strncmp(opt, "tc:", 3)) {
> > if (kstrtoint(opt + 3, 0, &tc))
> > goto err;
> > - } else if (sysfs_streq(opt, "watchdog:")) {
> > + } else if (!strncmp(opt, "watchdog:", 9)) {
> > if (kstrtoint(opt + 9, 0, &watchdog))
> > goto err;
> > - } else if (sysfs_streq(opt, "flow_ctrl:")) {
> > + } else if (!strncmp(opt, "flow_ctrl:", 10)) {
> > if (kstrtoint(opt + 10, 0, &flow_ctrl))
> > goto err;
> > - } else if (sysfs_streq(opt, "pause:", 6)) {
> > + } else if (!strncmp(opt, "pause:", 6)) {
> > if (kstrtoint(opt + 6, 0, &pause))
> > goto err;
> > - } else if (sysfs_streq(opt, "eee_timer:")) {
> > + } else if (!strncmp(opt, "eee_timer:", 10)) {
> > if (kstrtoint(opt + 10, 0, &eee_timer))
> > goto err;
> > - } else if (sysfs_streq(opt, "chain_mode:")) {
> > + } else if (!strncmp(opt, "chain_mode:", 11)) {
> > if (kstrtoint(opt + 11, 0, &chain_mode))
> > goto err;
> > }
> > --
> > 2.34.1
> >
Configuring via module options is bad idea.
If you have to do it don't roll your own key/value parsing.
If the driver just used regular module_param() for this it wouldn't have this crap.
Powered by blists - more mailing lists