Commit ba00e413 authored by Aiswarya Cyriac's avatar Aiswarya Cyriac Committed by Takashi Iwai
Browse files

ALSA: virtio: Fix "Coverity: virtsnd_kctl_tlv_op(): Uninitialized variables" warning. 



This commit fixes the following warning when building virtio_snd driver.

"
*** CID 1583619:  Uninitialized variables  (UNINIT)
sound/virtio/virtio_kctl.c:294 in virtsnd_kctl_tlv_op()
288
289     		break;
290     	}
291
292     	kfree(tlv);
293
vvv     CID 1583619:  Uninitialized variables  (UNINIT)
vvv     Using uninitialized value "rc".
294     	return rc;
295     }
296
297     /**
298      * virtsnd_kctl_get_enum_items() - Query items for the ENUMERATED element type.
299      * @snd: VirtIO sound device.
"

This warning is caused by the absence of the "default" branch in the
switch-block, and is a false positive because the kernel calls
virtsnd_kctl_tlv_op() only with values for op_flag processed in
this block.

Also, this commit unifies the cleanup path for all possible control
paths in the callback function.

Signed-off-by: default avatarAnton Yakovlev <anton.yakovlev@opensynergy.com>
Signed-off-by: default avatarAiswarya Cyriac <aiswarya.cyriac@opensynergy.com>
Reported-by: default avatarcoverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1583619 ("Uninitialized variables")
Fixes: d6568e3d ("ALSA: virtio: add support for audio controls")
Acked-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240216100643.688590-1-aiswarya.cyriac@opensynergy.com


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent ff16cbc4

sound/virtio/virtio_kctl.c

+15 −4
Original line number Diff line number Diff line
@@ -253,8 +253,8 @@ static int virtsnd_kctl_tlv_op(struct snd_kcontrol *kcontrol, int op_flag, 


	tlv = kzalloc(size, GFP_KERNEL);

	if (!tlv) {

		virtsnd_ctl_msg_unref(msg);

		return -ENOMEM;

		rc = -ENOMEM;

		goto on_msg_unref;

	}



	sg_init_one(&sg, tlv, size);
@@ -281,14 +281,25 @@ static int virtsnd_kctl_tlv_op(struct snd_kcontrol *kcontrol, int op_flag, 
			hdr->hdr.code =

				cpu_to_le32(VIRTIO_SND_R_CTL_TLV_COMMAND);



		if (copy_from_user(tlv, utlv, size))

		if (copy_from_user(tlv, utlv, size)) {

			rc = -EFAULT;

		else

			goto on_msg_unref;

		} else {

			rc = virtsnd_ctl_msg_send(snd, msg, &sg, NULL, false);

		}



		break;

	default:

		rc = -EINVAL;

		/* We never get here - we listed all values for op_flag */

		WARN_ON(1);

		goto on_msg_unref;

	}

	kfree(tlv);

	return rc;



on_msg_unref:

	virtsnd_ctl_msg_unref(msg);

	kfree(tlv);



	return rc;