From 9c2d437cb343a9a9e1c2d5dea4e0ae6a7d4fa0be Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Fri, 6 Jun 2014 15:43:16 -0400 Subject: avoid invalid use of va_arg in open reading the variadic mode argument is only valid when the O_CREAT flag is present. this probably does not matter, but is needed for formal correctness, and could affect LTO or other full-program analysis. --- src/fcntl/open.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'src/fcntl/open.c') diff --git a/src/fcntl/open.c b/src/fcntl/open.c index 088a28f7..5e5be1d7 100644 --- a/src/fcntl/open.c +++ b/src/fcntl/open.c @@ -5,11 +5,14 @@ int open(const char *filename, int flags, ...) { - mode_t mode; - va_list ap; - va_start(ap, flags); - mode = va_arg(ap, mode_t); - va_end(ap); + mode_t mode = 0; + + if (flags & O_CREAT) { + va_list ap; + va_start(ap, flags); + mode = va_arg(ap, mode_t); + va_end(ap); + } int fd = __sys_open_cp(filename, flags, mode); if (fd>=0 && (flags & O_CLOEXEC)) -- cgit v1.2.1