Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Bin Liu Subject: [PATCH 4.9 30/32] usb: musb: trace: fix NULL pointer dereference in musb_g_tx() Date: Tue, 8 May 2018 10:11:10 +0200 Message-Id: <20180508074013.539917378@linuxfoundation.org> In-Reply-To: <20180508074008.800421598@linuxfoundation.org> References: <20180508074008.800421598@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bin Liu commit 9aea9b6cc78d2b99b23d84fb2e0bc6e464c6569e upstream. The usb_request pointer could be NULL in musb_g_tx(), where the tracepoint call would trigger the NULL pointer dereference failure when parsing the members of the usb_request pointer. Move the tracepoint call to where the usb_request pointer is already checked to solve the issue. Fixes: fc78003e5345 ("usb: musb: gadget: add usb-request tracepoints") Cc: stable@vger.kernel.org # v4.8+ Signed-off-by: Bin Liu Signed-off-by: Greg Kroah-Hartman --- drivers/usb/musb/musb_gadget.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/usb/musb/musb_gadget.c +++ b/drivers/usb/musb/musb_gadget.c @@ -442,7 +442,6 @@ void musb_g_tx(struct musb *musb, u8 epn req = next_request(musb_ep); request = &req->request; - trace_musb_req_tx(req); csr = musb_readw(epio, MUSB_TXCSR); musb_dbg(musb, "<== %s, txcsr %04x", musb_ep->end_point.name, csr); @@ -481,6 +480,8 @@ void musb_g_tx(struct musb *musb, u8 epn u8 is_dma = 0; bool short_packet = false; + trace_musb_req_tx(req); + if (dma && (csr & MUSB_TXCSR_DMAENAB)) { is_dma = 1; csr |= MUSB_TXCSR_P_WZC_BITS;