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From: Jisheng Zhang <jszhang@kernel.org>
To: Minas Harutyunyan <hminas@synopsys.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] usb: dwc2: remove useless check of !chan
Date: Tue, 19 May 2026 14:00:01 +0800	[thread overview]
Message-ID: <20260519060001.13199-1-jszhang@kernel.org> (raw)

It looks a bit strange we check !chan after dereference of this pointer
with "if (chan->ep_type != USB_ENDPOINT_XFER_CONTROL)".

In fact, when entering the dwc2_hcd_save_data_toggle(), the chan won't
be NULL, because its caller or indirect caller has ensured this,
specifically, it's checked with below line in dwc2_hc_n_intr()

if (!chan) {
    dev_err(hsotg->dev, "## hc_ptr_array for channel is NULL ##\n");
    return;
}

This addresses the following issue reported by klocwork tool:
  - Suspicious dereference of pointer 'chan' before NULL check at
    line 518

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
---
 drivers/usb/dwc2/hcd_intr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/dwc2/hcd_intr.c b/drivers/usb/dwc2/hcd_intr.c
index 5c7538d498dd..397c63393c7f 100644
--- a/drivers/usb/dwc2/hcd_intr.c
+++ b/drivers/usb/dwc2/hcd_intr.c
@@ -515,7 +515,7 @@ void dwc2_hcd_save_data_toggle(struct dwc2_hsotg *hsotg,
 	u32 pid = (hctsiz & TSIZ_SC_MC_PID_MASK) >> TSIZ_SC_MC_PID_SHIFT;
 
 	if (chan->ep_type != USB_ENDPOINT_XFER_CONTROL) {
-		if (WARN(!chan || !chan->qh,
+		if (WARN(!chan->qh,
 			 "chan->qh must be specified for non-control eps\n"))
 			return;
 
-- 
2.53.0


             reply	other threads:[~2026-05-19  6:19 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-05-19  6:00 Jisheng Zhang [this message]
2026-05-19  9:27 ` [PATCH] usb: dwc2: remove useless check of !chan Greg Kroah-Hartman
2026-05-19 23:27   ` Jisheng Zhang

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