The next field of the DMA descriptor is written after releasing the descriptor, which may result in a use-after-free issue. Set the value of the field before it is released to fix the bug. Signed-off-by: Pan Bian <bianpan2016@xxxxxxx> --- drivers/usb/gadget/udc/pch_udc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/gadget/udc/pch_udc.c b/drivers/usb/gadget/udc/pch_udc.c index 265dab2bbfac..c5b8ec908aab 100644 --- a/drivers/usb/gadget/udc/pch_udc.c +++ b/drivers/usb/gadget/udc/pch_udc.c @@ -1518,8 +1518,8 @@ static void pch_udc_free_dma_chain(struct pch_udc_dev *dev, /* do not free first desc., will be done by free for request */ td = phys_to_virt(addr); addr2 = (dma_addr_t)td->next; - dma_pool_free(dev->data_requests, td, addr); td->next = 0x00; + dma_pool_free(dev->data_requests, td, addr); addr = addr2; } req->chain_len = 1; -- 2.7.4
