aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorSuwan Kim <suwan.kim027@gmail.com>2019-11-11 23:10:35 +0900
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-12-01 09:17:41 +0100
commit61f6a3fac394fb4f2325196d8fb4cd2b6c8a3ac7 (patch)
treea22e833a51801133ce18411adc17deb13825a9df
parent375b26a8648188957e2f3119c6cf078d3275bd74 (diff)
downloadlinux-yocto-61f6a3fac394fb4f2325196d8fb4cd2b6c8a3ac7.tar.gz
linux-yocto-61f6a3fac394fb4f2325196d8fb4cd2b6c8a3ac7.tar.bz2
linux-yocto-61f6a3fac394fb4f2325196d8fb4cd2b6c8a3ac7.zip
usbip: Fix uninitialized symbol 'nents' in stub_recv_cmd_submit()
commit 2a9125317b247f2cf35c196f968906dcf062ae2d upstream. Smatch reported that nents is not initialized and used in stub_recv_cmd_submit(). nents is currently initialized by sgl_alloc() and used to allocate multiple URBs when host controller doesn't support scatter-gather DMA. The use of uninitialized nents means that buf_len is zero and use_sg is true. But buffer length should not be zero when an URB uses scatter-gather DMA. To prevent this situation, add the conditional that checks buf_len and use_sg. And move the use of nents right after the sgl_alloc() to avoid the use of uninitialized nents. If the error occurs, it adds SDEV_EVENT_ERROR_MALLOC and stub_priv will be released by stub event handler and connection will be shut down. Fixes: ea44d190764b ("usbip: Implement SG support to vhci-hcd and stub driver") Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Suwan Kim <suwan.kim027@gmail.com> Acked-by: Shuah Khan <skhan@linuxfoundation.org> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20191111141035.27788-1-suwan.kim027@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/usb/usbip/stub_rx.c50
1 files changed, 32 insertions, 18 deletions
diff --git a/drivers/usb/usbip/stub_rx.c b/drivers/usb/usbip/stub_rx.c
index 75d8756c6d27..8c55cd833098 100644
--- a/drivers/usb/usbip/stub_rx.c
+++ b/drivers/usb/usbip/stub_rx.c
@@ -470,18 +470,50 @@ static void stub_recv_cmd_submit(struct stub_device *sdev,
if (pipe == -1)
return;
+ /*
+ * Smatch reported the error case where use_sg is true and buf_len is 0.
+ * In this case, It adds SDEV_EVENT_ERROR_MALLOC and stub_priv will be
+ * released by stub event handler and connection will be shut down.
+ */
priv = stub_priv_alloc(sdev, pdu);
if (!priv)
return;
buf_len = (unsigned long long)pdu->u.cmd_submit.transfer_buffer_length;
+ if (use_sg && !buf_len) {
+ dev_err(&udev->dev, "sg buffer with zero length\n");
+ goto err_malloc;
+ }
+
/* allocate urb transfer buffer, if needed */
if (buf_len) {
if (use_sg) {
sgl = sgl_alloc(buf_len, GFP_KERNEL, &nents);
if (!sgl)
goto err_malloc;
+
+ /* Check if the server's HCD supports SG */
+ if (!udev->bus->sg_tablesize) {
+ /*
+ * If the server's HCD doesn't support SG, break
+ * a single SG request into several URBs and map
+ * each SG list entry to corresponding URB
+ * buffer. The previously allocated SG list is
+ * stored in priv->sgl (If the server's HCD
+ * support SG, SG list is stored only in
+ * urb->sg) and it is used as an indicator that
+ * the server split single SG request into
+ * several URBs. Later, priv->sgl is used by
+ * stub_complete() and stub_send_ret_submit() to
+ * reassemble the divied URBs.
+ */
+ support_sg = 0;
+ num_urbs = nents;
+ priv->completed_urbs = 0;
+ pdu->u.cmd_submit.transfer_flags &=
+ ~URB_DMA_MAP_SG;
+ }
} else {
buffer = kzalloc(buf_len, GFP_KERNEL);
if (!buffer)
@@ -489,24 +521,6 @@ static void stub_recv_cmd_submit(struct stub_device *sdev,
}
}
- /* Check if the server's HCD supports SG */
- if (use_sg && !udev->bus->sg_tablesize) {
- /*
- * If the server's HCD doesn't support SG, break a single SG
- * request into several URBs and map each SG list entry to
- * corresponding URB buffer. The previously allocated SG
- * list is stored in priv->sgl (If the server's HCD support SG,
- * SG list is stored only in urb->sg) and it is used as an
- * indicator that the server split single SG request into
- * several URBs. Later, priv->sgl is used by stub_complete() and
- * stub_send_ret_submit() to reassemble the divied URBs.
- */
- support_sg = 0;
- num_urbs = nents;
- priv->completed_urbs = 0;
- pdu->u.cmd_submit.transfer_flags &= ~URB_DMA_MAP_SG;
- }
-
/* allocate urb array */
priv->num_urbs = num_urbs;
priv->urbs = kmalloc_array(num_urbs, sizeof(*priv->urbs), GFP_KERNEL);