Commit 469d258d authored by Vladimir Oltean's avatar Vladimir Oltean Committed by Jakub Kicinski

Revert "net: stmmac: use sysfs_streq() instead of strncmp()"

This reverts commit f72cd76b.
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: f72cd76b ("net: stmmac: use sysfs_streq() instead of strncmp()")
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: default avatarMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20221125105304.3012153-1-vladimir.oltean@nxp.comSigned-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 2816c986
......@@ -7562,31 +7562,31 @@ 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;
}
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment