Re: [PATCH 1/1] printk: fix parsing of "brl=" option

From: Joe Perches
Date: Tue Aug 23 2016 - 12:25:51 EST


On Tue, 2016-08-23 at 17:47 +0200, Nicolas Iooss wrote:
> Commit bbeddf52adc1 ("printk: move braille console support into separate
> braille.[ch] files") moved the parsing of braille-related options into
> _braille_console_setup(), changing the type of variable str from char*
> to char**. In this commit, memcmp(str, "brl,", 4) was correctly updated
> to memcmp(*str, "brl,", 4) but not memcmp(str, "brl=", 4).
>
> Update the code to make "brl=" option work again.
>
> Fixes: bbeddf52adc1 ("printk: move braille console support into separate
> braille.[ch] files")
> Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@xxxxxxx>
> ---
>  kernel/printk/braille.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/printk/braille.c b/kernel/printk/braille.c
> index 276762f3a460..f735ade8494c 100644
> --- a/kernel/printk/braille.c
> +++ b/kernel/printk/braille.c
> @@ -12,7 +12,7 @@ char *_braille_console_setup(char **str, char **brl_options)
>   if (!memcmp(*str, "brl,", 4)) {
>   *brl_options = "";
>   *str += 4;
> - } else if (!memcmp(str, "brl=", 4)) {
> + } else if (!memcmp(*str, "brl=", 4)) {
>   *brl_options = *str + 4;
>   *str = strchr(*brl_options, ',');
>   if (!*str)

Thanks.

likely the first memcmp here should be strcmp
and the second should be strncmp

That would have caused the compiler to show
the defect.