From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A77042D6E66; Thu, 20 Aug 2026 06:41:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787208103; cv=none; b=lWnFCDfNEFNIyBansft8vZDtSqE/fCtM/tspxUr+7V5X1R7lfKV760vZWN9a85UCfYYT8S4SPlUDbqO3KWxymWkdN2ZzRkKaXBD2e69Hd1SYRSj/aZAa/NxA01Wk6hs/mh0MG3DyyU5hzDLdzN1ymmoFafFR8tsLT9o9nyezfRw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787208103; c=relaxed/simple; bh=HK8OHhCdie3U5AlLwpuJTgkOi5q9uKYKu/UqlmZcOPA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LytZV34yvQHlC7U1OOnyV8kesR8ZE7PaiaEv3M97yRkc4cnkqz16LVe4K0sX6ITb341OchOz+iHvKbiXhcztZ5fppebLXFVdJfCiY1tx0Rknk9LrqEPNCIPYxg/2YBA6MjA/BGj88JAnPLSUTBTHY7yN/kFa3a+utaoURDaqFso= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ayMrNDda; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ayMrNDda" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B1B8E1F000E9; Thu, 20 Aug 2026 06:41:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787208101; bh=A6z0vphuW81DjBqaPEoBpamHJRxMbGMHk/J68SSKJFY=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=ayMrNDdapapuGTNEpg0lcsbzFuscoIaU2LOqwmTS7v8CQZsnjqvYaGno30rlsedXB NAAVHrvJavd3fYKpnNYUHLXuBtFiaBQWL1sWZg1iM+WTRsM52hj7RcvV1Nv7NRjp5m +t1Ur+HdAxN/UwEfX2w7RKtgb0vyfOvToWeLGlR0= Date: Thu, 20 Aug 2026 08:40:04 +0200 From: Greg KH To: Nguyen Quang Le Kien , eadavis@qq.com Cc: rafael@kernel.org, dakr@kernel.org, driver-core@lists.linux.dev, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+87188222c77c0dbbdb4d@syzkaller.appspotmail.com Subject: Re: [PATCH v2] driver core: avoid klist_remove() on unattached knode_driver Message-ID: <2026082048-malformed-finite-4e61@gregkh> References: <20260820055502.49963-1-khiemtranzo532001@gmail.com> <20260820060523.55087-1-khiemtranzo532001@gmail.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260820060523.55087-1-khiemtranzo532001@gmail.com> On Thu, Aug 20, 2026 at 02:05:23PM +0800, Nguyen Quang Le Kien wrote: > usb_driver_claim_interface() sets dev->driver directly and skips > device_bind_driver() when the interface is not yet registered, so the > device can reach teardown with dev->driver set but knode_driver never > added to the driver's klist_devices. __device_release_driver() then > unconditionally calls klist_remove() on the unattached node, which > dereferences a NULL klist pointer in klist_put() and crashes. > > Only remove the node if the device is actually bound, mirroring the > check device_is_bound() already provides for the driver core. This > matches the existing guard on knode_bus in bus_remove_device(). > > Reported-by: syzbot+87188222c77c0dbbdb4d@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=87188222c77c0dbbdb4d > Signed-off-by: Nguyen Quang Le Kien > --- > drivers/base/dd.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) What changed from v1? And why did you send the same patch as Edward Adam Davis just did: https://lore.kernel.org/r/tencent_0B76C5676E3DA13640962637444B28743709@qq.com What is suddenly causing people to care about syzbot bugs for USB? thanks, greg k-h