From 9b6083465fb8311f2410615f8303a41f580a2a20 Mon Sep 17 00:00:00 2001
From: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Date: Thu, 11 Jul 2024 10:38:49 +0300
Subject: [PATCH] virtio-snd: check for invalid param shift operands
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When setting the parameters of a PCM stream, we compute the bit flag
with the format and rate values as shift operand to check if they are
set in supported_formats and supported_rates.
If the guest provides a format/rate value which when shifting 1 results
in a value bigger than the number of bits in
supported_formats/supported_rates, we must report an error.
Previously, this ended up triggering the not reached assertions later
when converting to internal QEMU values.
Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2416
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-Id: <virtio-snd-fuzz-2416-fix-v1-manos.pitsidianakis@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
hw/audio/virtio-snd.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/hw/audio/virtio-snd.c b/hw/audio/virtio-snd.c
index e6432ac959..e5196aa4bb 100644
--- a/hw/audio/virtio-snd.c
+++ b/hw/audio/virtio-snd.c
@@ -282,11 +282,13 @@ uint32_t virtio_snd_set_pcm_params(VirtIOSound *s,
error_report("Number of channels is not supported.");
return cpu_to_le32(VIRTIO_SND_S_NOT_SUPP);
}
- if (!(supported_formats & BIT(params->format))) {
+ if (BIT(params->format) > sizeof(supported_formats) ||
+ !(supported_formats & BIT(params->format))) {
error_report("Stream format is not supported.");
return cpu_to_le32(VIRTIO_SND_S_NOT_SUPP);
}
- if (!(supported_rates & BIT(params->rate))) {
+ if (BIT(params->rate) > sizeof(supported_rates) ||
+ !(supported_rates & BIT(params->rate))) {
error_report("Stream rate is not supported.");
return cpu_to_le32(VIRTIO_SND_S_NOT_SUPP);
}
--
2.30.2