PR/56644 CVS commit: src/sys/dev/audio

["Tetsuya Isaki" <isaki%netbsd.org@localhost>]

The following reply was made to PR kern/56644; it has been noted by GNATS.

From: "Tetsuya Isaki" <isaki%netbsd.org@localhost>
To: gnats-bugs%gnats.NetBSD.org@localhost
Cc: 
Subject: PR/56644 CVS commit: src/sys/dev/audio
Date: Sat, 26 Mar 2022 06:27:32 +0000

 Module Name:	src
 Committed By:	isaki
 Date:		Sat Mar 26 06:27:32 UTC 2022
 
 Modified Files:
 	src/sys/dev/audio: audio.c
 
 Log Message:
 Fix conditions that audio_read() calls audio_track_record().
 audio_track_record() must be called when usrbuf has at least one free block.
 
 I hope that this will fix the panic reported in PR kern/56644.
 When an user process specifies the hardware format as its recording format
 (i.e., there is no track conversions), if the user process read(2) a small
 amount of data and the rmixer_process then runs, depending on the conditions,
 the panic may happen.  I have never reproduced it because it's difficult to
 do intentionally.
 
 Thanks Y.Sugahara and riastradh@ for help and comments.
 
 
 To generate a diff of this commit:
 cvs rdiff -u -r1.115 -r1.116 src/sys/dev/audio/audio.c
 
 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.