From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793829564; b=oZurqc34E7aVlByxfKL/WFXzSHahZjTRW/AIjhjvIkwQX8hUkm9dcQF+tu3x4kHV6gAS USK+3b6EZJbsHPaeMlJwFTdjF0+wvdadh4Fwg4ZX4/iUytphSbyNIiew8qatFW1c+tgaN BW1gIKLO38Nkp65rezEdAo8OyA4AJil4PRg1GkP7lCsuQPXJF3WyEaIUzhjnircRhuD0O O/aljxIWhtO+t1K0n4kvQSmDC3G9YILAFZy0aNiKp4VQJWif+Lq+MO9sGiCnc1NmenBAK ScZk8cUD7pKne+53B/9L5hX8OXVs7mwALpBVLiBJTfdcFmZpERHto/YgS4Ay4cZGDNQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793829564; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=qJ8YSbv4QI+ZxUIiiWeYJj/6ZlJHBZJAHga+kCDwPvo=; b=fgzHp/uJcN305BMz1BT9sFTtKjJ9tWVOSZbSfEbjg591TGtiVcnRZuI55KMPfIRPMnal VXavLP8MulWcooMv6F7B2MHxAYAQzhoTt/ixyPTGLs/Crd+0gz9CRG+WUgIXGNGwD2Wvu ZJWmFAcVnO7NIQ5tqiZYMPFUvehUiDHliCC4h/BXaGHsR7+fP4OCXsB3GheDfaAW46auC Z0mc8nVDcTyj9a2iNrXMj85oYXohGY6j+gH+C9PkTNaJWYwdidF2HOWbfjVSqSRHNPvOM LIG7bz0yr0Eo66C1kCljW+qOuRWvnOq7Wt4WQFopJ15H6e2bgD/TOI8L/9+LJSl9aJw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=uLxNDDUe; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 53776606A33E; Wed, 4 Nov 2026 21:59:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=uLxNDDUe Received: by smtp.kernel.org (Postfix) with ESMTPSA id E7E4C1F00A17; Wed, 4 Nov 2026 21:59:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793829564; bh=qJ8YSbv4QI+ZxUIiiWeYJj/6ZlJHBZJAHga+kCDwPvo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=uLxNDDUe47huViGV+AYwA4hz0W2ET99JBvA0Agedw+oicAnZY1ugXDNt3vsj2ySIW 9FFXHosxd4jBo97Uft5UCPBOGoAw/x8y4j85rvCh6HDmA0X3TikoqLY423m++UTPyv oL0CmmjJIeZvQ+14rJ/RrqOsRBjeMi8TGvmczZ8s= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ian Abbott , Sasha Levin Subject: [PATCH 6.18 0178/1005] comedi: pcm818: Fix sanity check in interrupt handler Date: Wed, 4 Nov 2026 15:58:31 -0500 Message-ID: <20261104211048.766294412@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211043.516122098@linuxfoundation.org> References: <20261104211043.516122098@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ian Abbott [ Upstream commit 956e8478261a575d1e87490f2e5db1788b8c209d ] The driver requests an interrupt handler for the device before it is fully set up. For safety, the interrupt handler checks the dev->attached flag to ensure the device is fully set up, but it currently does that after dereferencing the dev->read_dev pointer which may be NULL if dev->attached is false. Move the check to avoid the possible null pointer dereference. Signed-off-by: Ian Abbott Link: https://patch.msgid.link/20260618102949.26607-9-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/comedi/drivers/pcl818.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/comedi/drivers/pcl818.c b/drivers/comedi/drivers/pcl818.c index 06fe06396f23a..e8ce34840050a 100644 --- a/drivers/comedi/drivers/pcl818.c +++ b/drivers/comedi/drivers/pcl818.c @@ -534,13 +534,14 @@ static irqreturn_t pcl818_interrupt(int irq, void *d) struct comedi_device *dev = d; struct pcl818_private *devpriv = dev->private; struct comedi_subdevice *s = dev->read_subdev; - struct comedi_cmd *cmd = &s->async->cmd; + struct comedi_cmd *cmd; if (!dev->attached || !devpriv->ai_cmd_running) { pcl818_ai_clear_eoc(dev); return IRQ_HANDLED; } + cmd = &s->async->cmd; if (devpriv->ai_cmd_canceled) { /* * The cleanup from ai_cancel() has been delayed -- 2.53.0