Hi Pino, thanks for the report and the patch!
On Sun Oct 27, 2024 at 10:51 AM CET, Pino Toscano wrote:
While this is a (arguably minor) bug in the Hurd part of glibc, I'm
submitting a local workaround here for the following reasons:
- mdocml is the only occurrence of this recvmsg() bug I've found so far
- it affects only the existance test, the actual mdocml code works fine
(and the tests pass)
- submitting it to glibc and ensuring it is available in Debian will
take a while
I'm ok with adding the patch to the Debian package for now, but I don't
want to keep it here indefinitely. Could you please be sure a proper bug
report (or fix) is submitted to glibc?
Author: Pino Toscano <p...@debian.org>
Description: Pass non-null msghdr to recvmsg()
The Hurd implementation of recvmsg() in glibc does not handle a NULL value
for the msghdr parameter, crashing (and thus failing the test).
.
Since this is a simple existance test, and the actual mdocml code uses properly
filled msghdr's, then pass it a valid one also in the existance test.
.
This is a workaround for what glibc ought to handle better (i.e. not crash and
return EINVAL); use it to keep building mdocml while a proper fix is done in
glibc.
Forwarded: not-needed
Last-Update: 2014-10-27
I assume you meant 2024 here, right? (nice, descriptive patch
description by the way, good job!)
--- a/test-recvmsg.c
+++ b/test-recvmsg.c
@@ -1,8 +1,11 @@
#include <sys/socket.h>
#include <stddef.h>
+#include <string.h>
int
main(void)
{
- return recvmsg(-1, NULL, 0) != -1;
+ struct msghdr msg;
+ memset(&msg, 0, sizeof(msg));
+ return recvmsg(-1, &msg, 0) != -1;
Instead of creating a temporary variable explicitly, I'd use a compound
literal. This would also result in a one-line change, and would not
require including string.h.
- return recvmsg(-1, NULL, 0) != -1;
+ return recvmsg(-1, &(struct msghdr){0}, 0) != -1;
}
Thanks! Bye :)
