USB: fix linked-list corruption in rh_call_control()
commit 1633682053a7ee8058e10c76722b9b28e97fb73f upstream.
Using KASAN, Dmitry found a bug in the rh_call_control() routine: If
buffer allocation fails, the routine returns immediately without
unlinking its URB from the control endpoint, eventually leading to
linked-list corruption.
This patch fixes the problem by jumping to the end of the routine
(where the URB is unlinked) when an allocation failure occurs.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 479e223..f029aad 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -520,8 +520,10 @@
*/
tbuf_size = max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
tbuf = kzalloc(tbuf_size, GFP_KERNEL);
- if (!tbuf)
- return -ENOMEM;
+ if (!tbuf) {
+ status = -ENOMEM;
+ goto err_alloc;
+ }
bufp = tbuf;
@@ -734,6 +736,7 @@
}
kfree(tbuf);
+ err_alloc:
/* any errors get returned through the urb completion */
spin_lock_irq(&hcd_root_hub_lock);