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: Anton Yakovlev anton.yakovlev@opensynergy.com Signed-off-by: Aiswarya Cyriac aiswarya.cyriac@opensynergy.com Reported-by: coverity-bot keescook+coverity-bot@chromium.org Addresses-Coverity-ID: 1583619 ("Uninitialized variables") Fixes: d6568e3de42d ("ALSA: virtio: add support for audio controls") --- sound/virtio/virtio_kctl.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/sound/virtio/virtio_kctl.c b/sound/virtio/virtio_kctl.c index 0c6ac74aca1e..89e29a496dbe 100644 --- a/sound/virtio/virtio_kctl.c +++ b/sound/virtio/virtio_kctl.c @@ -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_cleanup; }

sg_init_one(&sg, tlv, size); @@ -266,6 +266,11 @@ static int virtsnd_kctl_tlv_op(struct snd_kcontrol *kcontrol, int op_flag, case SNDRV_CTL_TLV_OP_READ: hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_TLV_READ);

+ /* Since virtsnd_ctl_msg_send() drops the reference, we increase + * the counter to be consistent with the on_cleanup path. + */ + virtsnd_ctl_msg_ref(msg); + rc = virtsnd_ctl_msg_send(snd, msg, NULL, &sg, false); if (!rc) { if (copy_to_user(utlv, tlv, size)) @@ -281,14 +286,25 @@ 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 + } else { + /* Same as the comment above */ + virtsnd_ctl_msg_ref(msg); + rc = virtsnd_ctl_msg_send(snd, msg, &sg, NULL, false); + } + + break; + default: + rc = -EINVAL;

break; }

+on_cleanup: + virtsnd_ctl_msg_unref(msg); + kfree(tlv);

return rc;