From: Samuel Thibault <samuel.thibault@ens-lyon.org>
Date: Sun, 25 Aug 2024 01:35:29 +0000 (+0200)
Subject: mach: Fix bogus negative return
X-Git-Tag: glibc-2.41~715
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=f071795d80255755c4f3d2bdc6c55e67753b52b9;p=thirdparty%2Fglibc.git

mach: Fix bogus negative return

One can be very unlucky to call time_now first just before a second switch,
and mach_msg sleep just a bit more enough for the second time_now call to
count one second too many (or even more if scheduling is really unlucky).

So we have to protect against returning a bogus negative value in such case.
---

diff --git a/sysdeps/mach/sleep.c b/sysdeps/mach/sleep.c
index 572be150bc..aa750c13c5 100644
--- a/sysdeps/mach/sleep.c
+++ b/sysdeps/mach/sleep.c
@@ -43,6 +43,9 @@ __sleep (unsigned int seconds)
   after = time_now ();
   __mach_port_destroy (__mach_task_self (), recv);
 
+  if (after - before > seconds)
+    return 0;
+
   return seconds - (after - before);
 }
 weak_alias (__sleep, sleep)