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=1794060725; b=AhNPBO3PLB+MRRHQk9gvkXiwFo/NVZkivv05CufFJkqF2Abr6ybtWCnwIaHfuGhypYty 0IHfTLnq9i7tGMDznKv3Dy0oxewy+m/EI5U0rS6T7ZzONL4UM61fazjbHf6jOUDRrlVM5 B5+m1AP8Mgy+EsrNf+LsOt1AP6BLGORVvRquKCL8n3CiIo+fG+0qIZPBsuFoK1YIWSQEO TcMrMOlLoz193dafuR33q9Ztv718C0KGRXR29/RZP0RT1SAy9qFH2DWCy9S7ZRlIo+gI9 X+2TcXqOcdI+KZ4iEZWANMNM4bTH8b+1Gq6mksgbypNg51n7WKHCAviqZf0XEcgrW7w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794060725; 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=tR0F9FGg+cSZZyGqPdExwcBW4KyniPQedKp1wa36uhQ=; b=Dvc+FgELrPPEQ+soVvamgjHLz0ywoVfYFs9zEPUOh9XYs3hKXQXUjUAgcwbYJGjbHmNL DK65ZarX8x4+jurqFSdbq2xTIXftYlaCTsT6EDBvjCeQFFI0SlluDl14xwykmRbWcb1NB 8E+TNON7uIzkqbBYPzT5UBo2vnu/C3lO0PFFoPX3xSYNArq8pMGq7hYRUTrAHH4HkndRN 88WC++JFJwdoazBVuRoIwgZJ18bgoVhUZc+j99nmdPBN4tIwPR9FRWWyVAQI5Q9h4HCKH Ye2tRlNPpLvx4iVCN794pxBtX2e+vL9/sNyXt8CyWOrAbJ3GOokKGFVYTiFQeA3/H4A== 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=KqJ0GMV3; 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 22DD8606A333; Sat, 7 Nov 2026 14:12:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=KqJ0GMV3 Received: by smtp.kernel.org (Postfix) with ESMTPSA id C2B951F008A1; Sat, 7 Nov 2026 14:12:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794060725; bh=tR0F9FGg+cSZZyGqPdExwcBW4KyniPQedKp1wa36uhQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=KqJ0GMV3gepX1c+kHcZbivwC/R6bxKQqk6BYcvsQv9ZKF8C1cWo81YeNd3Y0aqURG WDxY8HroOQH/swb6TgKUurPXkIb5AO+rrxzmwpq4MtWHba6YOyzfThRsOpQ7c8QPMr 3NgNHTOx/mwHGo32SjF8LXfdb8R4BfOIDVy+/pTw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ian Abbott , Sasha Levin Subject: [PATCH 6.12 0145/1536] comedi: ni_at_a2150: Fix sanity check in interrupt handler Date: Sat, 7 Nov 2026 08:36:01 -0500 Message-ID: <20261107135001.762635179@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134957.653319350@linuxfoundation.org> References: <20261107134957.653319350@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ian Abbott [ Upstream commit e7356cdc7077a4f30fc5232a18e9fc6a4d404581 ] 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 various pointers which may be NULL if dev->attached is false. Move the check to avoid the possible null pointer dereferences. Signed-off-by: Ian Abbott Link: https://patch.msgid.link/20260618102949.26607-5-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/comedi/drivers/ni_at_a2150.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/comedi/drivers/ni_at_a2150.c b/drivers/comedi/drivers/ni_at_a2150.c index e4e5a0ebd195a..93e9591f5dd4c 100644 --- a/drivers/comedi/drivers/ni_at_a2150.c +++ b/drivers/comedi/drivers/ni_at_a2150.c @@ -132,11 +132,11 @@ static irqreturn_t a2150_interrupt(int irq, void *d) struct comedi_device *dev = d; struct a2150_private *devpriv = dev->private; struct comedi_isadma *dma = devpriv->dma; - struct comedi_isadma_desc *desc = &dma->desc[0]; + struct comedi_isadma_desc *desc; struct comedi_subdevice *s = dev->read_subdev; - struct comedi_async *async = s->async; - struct comedi_cmd *cmd = &async->cmd; - unsigned short *buf = desc->virt_addr; + struct comedi_async *async; + struct comedi_cmd *cmd; + unsigned short *buf; unsigned int max_points, num_points, residue, leftover; unsigned short dpnt; int status; @@ -145,6 +145,11 @@ static irqreturn_t a2150_interrupt(int irq, void *d) if (!dev->attached) return IRQ_HANDLED; + desc = &dma->desc[0]; + async = s->async; + cmd = &async->cmd; + buf = desc->virt_addr; + status = inw(dev->iobase + STATUS_REG); if ((status & INTR_BIT) == 0) return IRQ_NONE; -- 2.53.0