From 9aea9b6cc78d2b99b23d84fb2e0bc6e464c6569e Mon Sep 17 00:00:00 2001 From: Bin Liu Date: Mon, 30 Apr 2018 11:20:54 -0500 Subject: [PATCH] usb: musb: trace: fix NULL pointer dereference in musb_g_tx() 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(-) diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c index e564695c6c8d..71c5835ea9cd 100644 --- a/drivers/usb/musb/musb_gadget.c +++ b/drivers/usb/musb/musb_gadget.c @@ -417,7 +417,6 @@ void musb_g_tx(struct musb *musb, u8 epnum) 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); @@ -456,6 +455,8 @@ void musb_g_tx(struct musb *musb, u8 epnum) 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; -- 2.39.5