diff options
| -rw-r--r-- | tools/backlight_helper.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/tools/backlight_helper.c b/tools/backlight_helper.c index 11abebc2..24958ec6 100644 --- a/tools/backlight_helper.c +++ b/tools/backlight_helper.c @@ -17,7 +17,15 @@ int main(int argc, char *argv[]) return 1; } - snprintf(buf, sizeof(buf), "/sys/class/backlight/%s/brightness", argv[1]); + if (strchr(argv[1], '/') != NULL) { + fprintf(stderr, "Invalid interface name\n"); + return 1; + } + if (snprintf(buf, sizeof(buf), "/sys/class/backlight/%s/brightness", + argv[1]) >= sizeof(buf)) { + fprintf(stderr, "Interface name is too long\n"); + return 1; + } fd = open(buf, O_RDWR); if (fd < 0 || fstat(fd, &st) || major(st.st_dev)) { fprintf(stderr, "Cannot access backlight interface '%s'\n", argv[1]); |