From 417b11d3255c58cc2c33a74cf588d42a8cefbf95 Mon Sep 17 00:00:00 2001 From: Zubin Mithra Date: Fri, 27 Aug 2021 08:37:35 -0700 Subject: [PATCH] ALSA: pcm: fix divide error in snd_pcm_lib_ioctl commit f3eef46f0518a2b32ca1244015820c35a22cfe4a upstream. Syzkaller reported a divide error in snd_pcm_lib_ioctl. fifo_size is of type snd_pcm_uframes_t(unsigned long). If frame_size is 0x100000000, the error occurs. Fixes: a9960e6a293e ("ALSA: pcm: fix fifo_size frame calculation") Signed-off-by: Zubin Mithra Reviewed-by: Guenter Roeck Cc: Link: https://lore.kernel.org/r/20210827153735.789452-1-zsm@chromium.org Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/core/pcm_lib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 1662573a4030..fd300c3addde 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -1736,7 +1736,7 @@ static int snd_pcm_lib_ioctl_fifo_size(struct snd_pcm_substream *substream, channels = params_channels(params); frame_size = snd_pcm_format_size(format, channels); if (frame_size > 0) - params->fifo_size /= (unsigned)frame_size; + params->fifo_size /= frame_size; } return 0; }