[PATCH] fix two problems in tmf
From: Hu Tao
Date: Mon Mar 19 2012 - 03:58:22 EST
This patch fix two problems in tmf:
1. race in virtscsi_tmf that the cmd may have been already freed
when waking up from the completion
2. cmd leak if virtscsi_kick_cmd fails.
Signed-off-by: Hu Tao <hutao@xxxxxxxxxxxxxx>
---
drivers/scsi/virtio_scsi.c | 17 ++++++++++-------
1 files changed, 10 insertions(+), 7 deletions(-)
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index efccd72..3b8a6e6 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -175,7 +175,8 @@ static void virtscsi_complete_free(void *buf)
if (cmd->comp)
complete_all(cmd->comp);
- mempool_free(cmd, virtscsi_cmd_pool);
+ else
+ mempool_free(cmd, virtscsi_cmd_pool);
}
static void virtscsi_ctrl_done(struct virtqueue *vq)
@@ -311,21 +312,23 @@ out:
static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
{
DECLARE_COMPLETION_ONSTACK(comp);
- int ret;
+ int ret = FAILED;
cmd->comp = ∁
ret = virtscsi_kick_cmd(vscsi, vscsi->ctrl_vq, cmd,
sizeof cmd->req.tmf, sizeof cmd->resp.tmf,
GFP_NOIO);
if (ret < 0)
- return FAILED;
+ goto failed;
wait_for_completion(&comp);
- if (cmd->resp.tmf.response != VIRTIO_SCSI_S_OK &&
- cmd->resp.tmf.response != VIRTIO_SCSI_S_FUNCTION_SUCCEEDED)
- return FAILED;
+ if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK ||
+ cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED)
+ ret = SUCCESS;
- return SUCCESS;
+failed:
+ mempool_free(cmd, virtscsi_cmd_pool);
+ return ret;
}
static int virtscsi_device_reset(struct scsi_cmnd *sc)
--
1.7.1
--pWyiEgJYm5f9v55/--
--
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