[PATCH] kgdbts: fix return value of __setup handler

From: Randy Dunlap
Date: Mon Mar 07 2022 - 22:33:02 EST


__setup() handlers should return 1 to indicate that the boot option
has been handled. A return of 0 causes the boot option/value to be
listed as an Unknown kernel parameter and added to init's (limited)
environment strings. So return 1 from kgdbts_option_setup().

Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc7
kgdboc=kbd kgdbts=", will be passed to user space.

Run /sbin/init as init process
with arguments:
/sbin/init
with environment:
HOME=/
TERM=linux
BOOT_IMAGE=/boot/bzImage-517rc7
kgdboc=kbd
kgdbts=

Fixes: e8d31c204e36 ("kgdb: add kgdb internal test suite")
Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Reported-by: Igor Zhbanov <i.zhbanov@xxxxxxxxxxxx>
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@xxxxxxxxxxxx
Cc: kgdb-bugreport@xxxxxxxxxxxxxxxxxxxxx
Cc: Jason Wessel <jason.wessel@xxxxxxxxxxxxx>
Cc: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
Cc: Douglas Anderson <dianders@xxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/misc/kgdbts.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- lnx-517-rc7.orig/drivers/misc/kgdbts.c
+++ lnx-517-rc7/drivers/misc/kgdbts.c
@@ -1070,10 +1070,10 @@ static int kgdbts_option_setup(char *opt
{
if (strlen(opt) >= MAX_CONFIG_LEN) {
printk(KERN_ERR "kgdbts: config string too long\n");
- return -ENOSPC;
+ return 1;
}
strcpy(config, opt);
- return 0;
+ return 1;
}

__setup("kgdbts=", kgdbts_option_setup);