usb: xhci: Add error handling in xhci_map_urb_for_dma

Currently xhci_map_urb_for_dma() creates a temporary buffer and copies
the SG list to the new linear buffer. But if the kzalloc_node() fails,
then the following sg_pcopy_to_buffer() can lead to crash since it
tries to memcpy to NULL pointer.

So return -ENOMEM if kzalloc returns null pointer.

Cc: [e-mail] # 5.11
Fixes: 2017a1e58472 ("usb: xhci: Use temporary buffer to consolidate SG")
Signed-off-by: Prashanth K <[e-mail]>
Signed-off-by: Mathias Nyman <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/host/xhci.c

···
 
 	temp = kzalloc_node(buf_len, GFP_ATOMIC,
 			    dev_to_node(hcd->self.sysdev));
+	if (!temp)
+		return -ENOMEM;
 
 	if (usb_urb_dir_out(urb))
 		sg_pcopy_to_buffer(urb->sg, urb->num_sgs,