From: Alan Stern <[email protected]> 3.12-stable review patch. If anyone has any objections, please let me know.
=============== 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 <[email protected]> Reported-and-tested-by: Dmitry Vyukov <[email protected]> Signed-off-by: Jiri Slaby <[email protected]> --- drivers/usb/core/hcd.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 79055b3df45a..9925e4b6e2d3 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -498,8 +498,10 @@ static int rh_call_control (struct usb_hcd *hcd, struct urb *urb) */ 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; @@ -702,6 +704,7 @@ error: } kfree(tbuf); + err_alloc: /* any errors get returned through the urb completion */ spin_lock_irq(&hcd_root_hub_lock); -- 2.12.2
