From mboxrd@z Thu Jan  1 00:00:00 1970
X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/12921
Path: news.gmane.org!.POSTED!not-for-mail
From: Szabolcs Nagy <nsz@port70.net>
Newsgroups: gmane.linux.lib.musl.general
Subject: Re: broken __kernel_mode_t affecting some big endian archs
Date: Sat, 16 Jun 2018 02:14:24 +0200
Message-ID: <20180616001423.GS4418@port70.net>
References: <20180614005442.GK1392@brightrain.aerifal.cx>
 <20180615020023.GM1392@brightrain.aerifal.cx>
 <20180615020154.GN1392@brightrain.aerifal.cx>
Reply-To: musl@lists.openwall.com
NNTP-Posting-Host: blaine.gmane.org
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Trace: blaine.gmane.org 1529107953 27190 195.159.176.226 (16 Jun 2018 00:12:33 GMT)
X-Complaints-To: usenet@blaine.gmane.org
NNTP-Posting-Date: Sat, 16 Jun 2018 00:12:33 +0000 (UTC)
User-Agent: Mutt/1.9.1 (2017-09-22)
To: musl@lists.openwall.com
Original-X-From: musl-return-12937-gllmg-musl=m.gmane.org@lists.openwall.com Sat Jun 16 02:12:29 2018
Return-path: <musl-return-12937-gllmg-musl=m.gmane.org@lists.openwall.com>
Envelope-to: gllmg-musl@m.gmane.org
Original-Received: from mother.openwall.net ([195.42.179.200])
	by blaine.gmane.org with smtp (Exim 4.84_2)
	(envelope-from <musl-return-12937-gllmg-musl=m.gmane.org@lists.openwall.com>)
	id 1fTypR-000705-58
	for gllmg-musl@m.gmane.org; Sat, 16 Jun 2018 02:12:29 +0200
Original-Received: (qmail 9258 invoked by uid 550); 16 Jun 2018 00:14:36 -0000
Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm
Precedence: bulk
List-Post: <mailto:musl@lists.openwall.com>
List-Help: <mailto:musl-help@lists.openwall.com>
List-Unsubscribe: <mailto:musl-unsubscribe@lists.openwall.com>
List-Subscribe: <mailto:musl-subscribe@lists.openwall.com>
List-ID: <musl.lists.openwall.com>
Original-Received: (qmail 9235 invoked from network); 16 Jun 2018 00:14:35 -0000
Mail-Followup-To: musl@lists.openwall.com
Content-Disposition: inline
In-Reply-To: <20180615020154.GN1392@brightrain.aerifal.cx>
Xref: news.gmane.org gmane.linux.lib.musl.general:12921
Archived-At: <http://permalink.gmane.org/gmane.linux.lib.musl.general/12921>

* Rich Felker <dalias@libc.org> [2018-06-14 22:01:54 -0400]:
> diff --git a/src/ipc/shmctl.c b/src/ipc/shmctl.c
> index e2879f2..9d723d9 100644
> --- a/src/ipc/shmctl.c
> +++ b/src/ipc/shmctl.c
> @@ -4,9 +4,23 @@
>  
>  int shmctl(int id, int cmd, struct shmid_ds *buf)
>  {
> +#ifdef SYSCALL_IPC_BROKEN_MODE
> +	struct shmid_ds tmp;
> +	if (cmd == IPC_SET) {
> +		tmp = *buf;
> +		tmp.shm_perm.mode *= 0x10000U;
> +		buf = &tmp;
> +	}
> +#endif
>  #ifdef SYS_shmctl
> -	return syscall(SYS_shmctl, id, cmd | IPC_64, buf);
> +	int r = __syscall(SYS_shmctl, id, cmd | IPC_64, buf);
>  #else
> -	return syscall(SYS_ipc, IPCOP_shmctl, id, cmd | IPC_64, 0, buf, 0);
> +	int r = __syscall(SYS_ipc, IPCOP_shmctl, id, cmd | IPC_64, 0, buf, 0);
> +#endif
> +#ifdef SYSCALL_IPC_BROKEN_MODE
> +	if (r >= 0 && cmd == IPC_STAT) {
> +		buf->shm_perm.mode >>= 16;
> +	}
>  #endif
> +	return __syscall_ret(r);
>  }

ugly but looks ok to me.
i don't think there is a clean solution on the broken targets.