Date: Fri, 15 Apr 2011 21:34:12 GMT From: Grigori Goronzy <greg@chown.ath.cx> To: freebsd-gnats-submit@FreeBSD.org Subject: kern/156433: [sound] [patch] OSS4/VPC is broken on 64-bit platforms Message-ID: <201104152134.p3FLYCCd027612@red.freebsd.org> Resent-Message-ID: <201104152140.p3FLe7qc072000@freefall.freebsd.org>
next in thread | raw e-mail | index | archive | help
>Number: 156433
>Category: kern
>Synopsis: [sound] [patch] OSS4/VPC is broken on 64-bit platforms
>Confidential: no
>Severity: non-critical
>Priority: medium
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Fri Apr 15 21:40:07 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator: Grigori Goronzy
>Release: RELENG_8
>Organization:
>Environment:
FreeBSD fbsd.chown.ath.cx 8.2-RELEASE FreeBSD 8.2-RELEASE #1: Fri Apr 15 19:04:14 UTC 2011 root@fbsd.chown.ath.cx:/usr/obj/usr/src/sys/MINE amd64
>Description:
The OSS4 API for volume control is broken on 64-bit platforms. I tracked it down and noticed that the ioctl passthrough/wrapper uses "int" where it should use an "u_long" for passing ioctl parameters. On most 32-bit platforms this is not an issue, as sizeof(int)==sizeof(u_long). Not so on 64-bit platforms, though.
This boils down to a signed vs unsigned issue when the parameter is converted from int to u_long. This affects the SNDCTL_DSP_SETPLAYVOL ioctl and possibly others.
>How-To-Repeat:
1. Install mplayer2
2. Play an audio file through mplayer2's OSS output (which uses the aforementioned API call)
3. Try to change volume with "9" and "0" keys
4. Nothing happens
>Fix:
The attached patch.
Patch attached with submission follows:
--- sys/dev/sound/pcm/dsp.c.orig 2011-04-15 20:24:23.000000000 +0000
+++ sys/dev/sound/pcm/dsp.c 2011-04-15 20:38:30.000000000 +0000
@@ -1055,7 +1055,8 @@
{
struct pcm_channel *chn, *rdch, *wrch;
struct snddev_info *d;
- int *arg_i, ret, tmp, xcmd;
+ int *arg_i, ret, tmp;
+ u_long xcmd;
d = dsp_get_info(i_dev);
if (!DSP_REGISTERED(d, i_dev))
>Release-Note:
>Audit-Trail:
>Unformatted:
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201104152134.p3FLYCCd027612>