From 63ccd26cd1f6600421795f6ca3e625076be06c9f Mon Sep 17 00:00:00 2001 From: Frode Isaksen Date: Thu, 3 Apr 2025 09:28:03 +0200 Subject: [PATCH] usb: dwc3: gadget: check that event count does not exceed event buffer length The event count is read from register DWC3_GEVNTCOUNT. There is a check for the count being zero, but not for exceeding the event buffer length. Check that event count does not exceed event buffer length, avoiding an out-of-bounds access when memcpy'ing the event. Crash log: Unable to handle kernel paging request at virtual address ffffffc0129be000 pc : __memcpy+0x114/0x180 lr : dwc3_check_event_buf+0xec/0x348 x3 : 0000000000000030 x2 : 000000000000dfc4 x1 : ffffffc0129be000 x0 : ffffff87aad60080 Call trace: __memcpy+0x114/0x180 dwc3_interrupt+0x24/0x34 Signed-off-by: Frode Isaksen Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver") Cc: stable Acked-by: Thinh Nguyen Link: https://lore.kernel.org/r/20250403072907.448524-1-fisaksen@baylibre.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc3/gadget.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 47e73c4ed62d..8c30d86cc4e3 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -4617,6 +4617,12 @@ static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt) if (!count) return IRQ_NONE; + if (count > evt->length) { + dev_err_ratelimited(dwc->dev, "invalid count(%u) > evt->length(%u)\n", + count, evt->length); + return IRQ_NONE; + } + evt->count = count; evt->flags |= DWC3_EVENT_PENDING; -- 2.50.1