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usb: core: Check URB setup_packet and transfer_buffer sanity

Update usb_hcd_map_urb_for_dma() to check for an URB's setup_packet and
transfer_buffer sanity. We first check that urb->setup_packet is neither
coming from vmalloc space nor is an on stack buffer, and if that's the
case, produce a warning and return an error. For urb->transfer_buffer
there is an existing is_vmalloc_addr() check so we just supplement that
with an object_is_on_stack() check, produce a warning if that is the case
and also return an error.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Florian Fainelli 8 years ago
parent
commit
4568136620
1 changed files with 12 additions and 0 deletions
  1. 12 0
      drivers/usb/core/hcd.c

+ 12 - 0
drivers/usb/core/hcd.c

@@ -26,6 +26,7 @@
 #include <linux/module.h>
 #include <linux/version.h>
 #include <linux/kernel.h>
+#include <linux/sched/task_stack.h>
 #include <linux/slab.h>
 #include <linux/completion.h>
 #include <linux/utsname.h>
@@ -1523,6 +1524,14 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
 		if (hcd->self.uses_pio_for_control)
 			return ret;
 		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
+			if (is_vmalloc_addr(urb->setup_packet)) {
+				WARN_ONCE(1, "setup packet is not dma capable\n");
+				return -EAGAIN;
+			} else if (object_is_on_stack(urb->setup_packet)) {
+				WARN_ONCE(1, "setup packet is on stack\n");
+				return -EAGAIN;
+			}
+
 			urb->setup_dma = dma_map_single(
 					hcd->self.sysdev,
 					urb->setup_packet,
@@ -1587,6 +1596,9 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
 			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
 				WARN_ONCE(1, "transfer buffer not dma capable\n");
 				ret = -EAGAIN;
+			} else if (object_is_on_stack(urb->transfer_buffer)) {
+				WARN_ONCE(1, "transfer buffer is on stack\n");
+				ret = -EAGAIN;
 			} else {
 				urb->transfer_dma = dma_map_single(
 						hcd->self.sysdev,