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.
This commit is contained in:
Rich Felker 2014-06-06 15:43:16 -04:00
parent 7765706c05
commit 9c2d437cb3
1 changed files with 8 additions and 5 deletions

View File

@ -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))