diff options
author | Logan Gunthorpe <logang@deltatee.com> | 2019-02-19 12:56:36 -0700 |
---|---|---|
committer | Jon Mason <jdmason@kudzu.us> | 2019-06-13 08:58:12 -0400 |
commit | 51cb8dbf13246a0b144bff01d7d617efe550a055 (patch) | |
tree | 21287fecc3e86f22c6edc800102281d9d14377cc | |
parent | a5c3666f1c32714d8ee8735a129a9f13773135ba (diff) | |
download | linux-51cb8dbf13246a0b144bff01d7d617efe550a055.tar.bz2 |
NTB: ntb_transport: Ensure qp->tx_mw_dma_addr is initaliazed
Dan Carpenter's static checker reported:
drivers/ntb/ntb_transport.c:1926 ntb_transport_create_queue()
error: we previously assumed 'qp->tx_dma_chan' could be null (see line 1872)
This is because the tx_mw_dma_addr is uninitialized in this function and
may be incorrectly released using a NULL DMA channel.
In practice this bug will not likely be seen. I'd guess you could hit
this if you loaded ntb_netdev with use_dma=True, then unloaded it and
loaded it again after setting the module parameter to use_dma=False.
To fix this, we simply ensure that tx_mw_dma_addr is always
initialized to zero. This is the safest in case any other part of the
code operates on it if it is non-zero.
Fixes: c59666bb32b9 ("NTB: ntb_transport: Ensure the destination buffer is mapped for TX DMA")
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
-rw-r--r-- | drivers/ntb/ntb_transport.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c index d4f39ba1d976..99033228dccb 100644 --- a/drivers/ntb/ntb_transport.c +++ b/drivers/ntb/ntb_transport.c @@ -1869,6 +1869,7 @@ ntb_transport_create_queue(void *data, struct device *client_dev, qp->rx_dma_chan = NULL; } + qp->tx_mw_dma_addr = 0; if (qp->tx_dma_chan) { qp->tx_mw_dma_addr = dma_map_resource(qp->tx_dma_chan->device->dev, |