lkml.org 
[lkml]   [2020]   [Mar]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v3] gpio-hammer: Avoid potential overflow in main
czw., 12 mar 2020 o 15:50 Gabriel Ravier <gabravier@gmail.com> napisał(a):
>
> If '-o' was used more than 64 times in a single invocation of gpio-hammer,
> this could lead to an overflow of the 'lines' array. This commit fixes
> this by avoiding the overflow and giving a proper diagnostic back to the
> user
>
> Signed-off-by: Gabriel Ravier <gabravier@gmail.com>
> ---
> tools/gpio/gpio-hammer.c | 17 ++++++++++++++++-
> 1 file changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/tools/gpio/gpio-hammer.c b/tools/gpio/gpio-hammer.c
> index 0e0060a6e..083399d27 100644
> --- a/tools/gpio/gpio-hammer.c
> +++ b/tools/gpio/gpio-hammer.c
> @@ -135,7 +135,14 @@ int main(int argc, char **argv)
> device_name = optarg;
> break;
> case 'o':
> - lines[i] = strtoul(optarg, NULL, 10);
> + /*
> + * Avoid overflow. Do not immediately error, we want to
> + * be able to accurately report on the amount of times
> + * '-o' was given to give an accurate error message
> + */
> + if (i < GPIOHANDLES_MAX)
> + lines[i] = strtoul(optarg, NULL, 10);
> +
> i++;
> break;
> case '?':
> @@ -143,6 +150,14 @@ int main(int argc, char **argv)
> return -1;
> }
> }
> +
> + if (i >= GPIOHANDLES_MAX) {
> + fprintf(stderr,
> + "Only %d occurences of '-o' are allowed, %d were found\n",
> + GPIOHANDLES_MAX, i + 1);
> + return -1;
> + }
> +
> nlines = i;
>
> if (!device_name || !nlines) {
> --
> 2.24.1
>

Patch applied, thanks!

Bartosz

\
 
 \ /
  Last update: 2020-03-15 03:06    [W:0.031 / U:0.544 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site