select, pselect: Fix test failure on native Windows.

* lib/select.c (rpl_select): Fail if nfds is out-of-range.
* lib/pselect.c (pselect): Likewise.

3 files changed, 17 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 8d39a64023..587b210323 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2023-04-24  Bruno Haible  <bruno@clisp.org>
+
+	select, pselect: Fix test failure on native Windows.
+	* lib/select.c (rpl_select): Fail if nfds is out-of-range.
+	* lib/pselect.c (pselect): Likewise.
+
 2023-04-24  Paul Eggert  <eggert@cs.ucla.edu>
 
 	fclose: pacify gcc -Wanalyzer-file-leak
diff --git a/lib/pselect.c b/lib/pselect.c
index f5d21e1048..52d3837878 100644
--- a/lib/pselect.c
+++ b/lib/pselect.c
@@ -45,6 +45,12 @@ pselect (int nfds, fd_set *restrict rfds,
   sigset_t origmask;
   struct timeval tv, *tvp;
 
+  if (nfds < 0 || nfds > FD_SETSIZE)
+    {
+      errno = EINVAL;
+      return -1;
+    }
+
   if (timeout)
     {
       if (! (0 <= timeout->tv_nsec && timeout->tv_nsec < 1000000000))
diff --git a/lib/select.c b/lib/select.c
index 3d3efff3de..6b6ca4154c 100644
--- a/lib/select.c
+++ b/lib/select.c
@@ -279,8 +279,11 @@ rpl_select (int nfds, fd_set *rfds, fd_set *wfds, fd_set *xfds,
   int i, fd, rc;
   clock_t tend;
 
-  if (nfds > FD_SETSIZE)
-    nfds = FD_SETSIZE;
+  if (nfds < 0 || nfds > FD_SETSIZE)
+    {
+      errno = EINVAL;
+      return -1;
+    }
 
   if (!timeout)
     wait_timeout = INFINITE;