Remove dead store to f and avoid use of unvalidated fd.

Found by LLVM scan-build.

OK millert@ deraadt@

diff --git a/sys/lib/libsa/readdir.c b/sys/lib/libsa/readdir.c
index 76ff973..ab55059 100644 (file)
--- a/sys/lib/libsa/readdir.c
+++ b/sys/lib/libsa/readdir.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: readdir.c,v 1.9 2014/11/19 20:28:56 miod Exp $        */
+/*     $OpenBSD: readdir.c,v 1.10 2022/01/11 06:35:03 visa Exp $       */
 
 /*
  * Copyright (c) 1996 Michael Shalayeff
@@ -65,14 +65,17 @@ opendir(const char *name)
 int
 readdir(int fd, char *dest)
 {
-       struct open_file *f = &files[fd];
+       struct open_file *f;
 
-       if (fd < 0 || fd >= SOPEN_MAX ||
-           !((f = &files[fd])->f_flags & F_READ)) {
+       if (fd < 0 || fd >= SOPEN_MAX) {
+               errno = EBADF;
+               return (-1);
+       }
+       f = &files[fd];
+       if (!(f->f_flags & F_READ)) {
                errno = EBADF;
                return (-1);
        }
-
        if (f->f_flags & F_RAW) {
                errno = EOPNOTSUPP;
                return (-1);