From 86f82f3de1da07ef86a33a8e9302c98dafbfa6ec Mon Sep 17 00:00:00 2001 From: Daniel Golle Date: Tue, 31 Aug 2021 00:35:53 +0100 Subject: [PATCH] utils: don't ignore open() return value In case active console cannot be opened, return NULL early instead of trying to read from errornous file descriptor. Coverity CID: 1490087 Argument cannot be negative Signed-off-by: Daniel Golle --- utils/utils.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/utils/utils.c b/utils/utils.c index 2cfcc8e..f0c4a90 100644 --- a/utils/utils.c +++ b/utils/utils.c @@ -139,7 +139,12 @@ char *get_active_console(char *out, int len) { char line[CMDLINE_SIZE + 1]; int fd = open("/sys/class/tty/console/active", O_RDONLY); - ssize_t r = read(fd, line, sizeof(line) - 1); + ssize_t r; + + if (fd < 0) + return NULL; + + r = read(fd, line, sizeof(line) - 1); line[CMDLINE_SIZE] = '\0'; close(fd); -- 2.30.2