On Thu, Jan 31, 2019 at 12:43:12PM -0700, Shuah Khan wrote:
> Fix the following warning by sizing the buffer to max. of sysfs
> path max. size + d_name max. size.
>
> gcc -Wall -O2 -I../../../include/uapi ir_loopback.c -o ../tools/testing/selftests/ir/ir_loopback
> ir_loopback.c: In function ‘lirc_open’:
> ir_loopback.c:71:37: warning: ‘%s’ directive output may be truncated writing up to 255 bytes into a region of size 95 [-Wformat-truncation=]
> snprintf(buf, sizeof(buf), "/dev/%s", dent->d_name);
> ^~
> In file included from /usr/include/stdio.h:862:0,
> from ir_loopback.c:14:
> /usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: ‘__builtin___snprintf_chk’ output between 6 and 261 bytes into a destination of size 100
> return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> __bos (__s), __fmt, __va_arg_pack ());
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Signed-off-by: Shuah Khan <shuah@xxxxxxxxxx>
Thank you for catching and fixing these. For all three patches:
Acked-by: Sean Young <sean@xxxxxxxx>
> ---
> tools/testing/selftests/ir/ir_loopback.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/ir/ir_loopback.c b/tools/testing/selftests/ir/ir_loopback.c
> index 858c19caf224..8cdf1b89ac9c 100644
> --- a/tools/testing/selftests/ir/ir_loopback.c
> +++ b/tools/testing/selftests/ir/ir_loopback.c
> @@ -27,6 +27,8 @@
>
> #define TEST_SCANCODES 10
> #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
> +#define SYSFS_PATH_MAX 256
> +#define DNAME_PATH_MAX 256
>
> static const struct {
> enum rc_proto proto;
> @@ -56,7 +58,7 @@ static const struct {
> int lirc_open(const char *rc)
> {
> struct dirent *dent;
> - char buf[100];
> + char buf[SYSFS_PATH_MAX + DNAME_PATH_MAX];
> DIR *d;
> int fd;
>
> --
> 2.17.1
