Server crash on receiving query

[Ondřej Surý]

I spent last two hours crashing my computer while bisecting the issue,
and you would not have guessed the commit that causes this:

commit f063ee276e4a7f6cfccbefa969e8db8df952348b
Author: Ondřej Surý <ondrej at isc.org>
Date:   2022-05-18 14:10:58 +0200

    Use libuv CFLAGS and LIBS when checking for features

    When autoconf was checking for libuv features, the LIBUV_CFLAGS was not
    added to CFLAGS and LIBUV_LIBS to LIBS which resulted in false
    negatives.

    Use AX_SAVE_FLAGS and AX_RESTORE_FLAGS to temporarily add LIBUV_CFLAGS
    and LIBUV_LIBS to their respective variables.

diff --git a/configure.ac b/configure.ac
index 8dc5aca4c4..84108c9820 100644
--- a/configure.ac
+++ b/configure.ac
@@ -557,6 +557,10 @@ AC_MSG_CHECKING([for libuv])
 PKG_CHECK_MODULES([LIBUV], [libuv >= 1.0.0], [],
   [AC_MSG_ERROR([libuv not found])])

+AX_SAVE_FLAGS([libuv])
+CFLAGS="$CFLAGS $LIBUV_CFLAGS"
+LIBS="$LIBS $LIBUV_LIBS"
+
 # libuv recvmmsg support
 AC_CHECK_DECLS([UV_UDP_MMSG_FREE, UV_UDP_MMSG_CHUNK], [], [], [[#include <uv.h>]])
 AC_MSG_CHECKING([whether struct msghdr uses padding for alignment])
@@ -571,6 +575,8 @@ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <sys/socket.h>],
 # libuv recverr support
 AC_CHECK_DECLS([UV_UDP_LINUX_RECVERR], [], [], [[#include <uv.h>]])

+AX_RESTORE_FLAGS([libuv])
+
 # [pairwise: --enable-doh --with-libnghttp2=auto, --enable-doh --with-libnghttp2=yes, --disable-doh]
 AC_ARG_ENABLE([doh],
       [AS_HELP_STRING([--disable-doh], [enable DNS over HTTPS, requires libnghttp2 (default=yes)])],

The bug has been reported to Apple now as a security issue.

Ondrej
--
Ondřej Surý (He/Him)
ondrej at isc.org

My working hours and your working hours may be different. Please do not feel obligated to reply outside your normal working hours.

> On 4. 11. 2024, at 15:03, Scott Bradner <sob at sobco.com> wrote:
> 
> for what its worth - I am NOT framing this as a BIND 9 fault  as in BIND should
> change what it is doing 
> 
> but BIND 9 is doing something that Apple does not like  and it would
> help Apple to know what that is
> 
> Scott
> 
>> On Nov 4, 2024, at 9:59 AM, Ondřej Surý <ondrej at isc.org> wrote:
>> 
>> Please stop framing this as this is BIND 9 fault. I’ll report this to Apple as I can reproduce this on my machine too on unprivileged account.
>> 
>> Ondrej
>> --
>> Ondřej Surý — ISC (He/Him)
>> 
>> My working hours and your working hours may be different. Please do not feel obligated to reply outside your normal working hours.
>> 
>>> On 4. 11. 2024, at 14:23, Scott Bradner <sob at sobco.com> wrote:
>>> 
>>> does named so something in buffering previous queries that would
>>> trigger a different process on the third query?  (seems strange that
>>> its reboot from another computer is repeatable on the 3rd query for the
>>> same site?)
>>> 
>>> note that many queries from another computer are just fine as long as its
>>> not for the same site
>>> 
>>> Scott
>>> 
>>>>> On Nov 4, 2024, at 9:16 AM, Ondřej Surý <ondrej at isc.org> wrote:
>>>>> 
>>>>> maybe named is using some special system call
>>>> 
>>>> Named is not using anything special. All the stuff is just libraries and standard API.
>>>> 
>>>> Ondrej
>>>> --
>>>> Ondřej Surý — ISC (He/Him)
>>>> 
>>>> My working hours and your working hours may be different. Please do not feel obligated to reply outside your normal working hours.
>>>> 
>>>>>> On 4. 11. 2024, at 14:14, Scott Bradner <sob at sobco.com> wrote:
>>>>> 
>>>>> maybe named is using some special system call
>>>> 
>>> 
>> 
>