From nobody Fri Dec 19 00:01:08 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EDCBEC38A2D for ; Mon, 24 Oct 2022 16:40:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234458AbiJXQkZ (ORCPT ); Mon, 24 Oct 2022 12:40:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47274 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234244AbiJXQjr (ORCPT ); Mon, 24 Oct 2022 12:39:47 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A656156BB5; Mon, 24 Oct 2022 08:26:52 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id AD092B81996; Mon, 24 Oct 2022 12:43:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 13C91C433D7; Mon, 24 Oct 2022 12:43:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666615387; bh=cNB5yuiLH6ZtpQ2wUOYKIZtk5Q/9DzwbtN7X7TPvm3A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aDrST+/mCfNt0B3LL877g6ZEfU7ryWhc8eO2DwdX6jFC4CXJGumCOCZvh8FNT3Iiy 7FHbdcVdt6R/oJBiKyzh08mQrJlbQez1icbAWh1SnmX5tPORA5hPbzLnY6JhE39/v2 bG1l6UWGDsOzKQa90JToCekKTmNznMK5v96BigvQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marek Szyprowski , Mark Brown , Sasha Levin Subject: [PATCH 5.15 200/530] spi: Ensure that sg_table wont be used after being freed Date: Mon, 24 Oct 2022 13:29:04 +0200 Message-Id: <20221024113054.107478506@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024113044.976326639@linuxfoundation.org> References: <20221024113044.976326639@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Marek Szyprowski [ Upstream commit 8e9204cddcc3fea9affcfa411715ba4f66e97587 ] SPI code checks for non-zero sgt->orig_nents to determine if the buffer has been DMA-mapped. Ensure that sg_table is really zeroed after free to avoid potential NULL pointer dereference if the given SPI xfer object is reused again without being DMA-mapped. Fixes: 0c17ba73c08f ("spi: Fix cache corruption due to DMA/PIO overlap") Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20220930113408.19720-1-m.szyprowski@samsung= .com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 556d65af5e23..06dd1be54925 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1007,6 +1007,8 @@ void spi_unmap_buf(struct spi_controller *ctlr, struc= t device *dev, if (sgt->orig_nents) { dma_unmap_sg(dev, sgt->sgl, sgt->orig_nents, dir); sg_free_table(sgt); + sgt->orig_nents =3D 0; + sgt->nents =3D 0; } } =20 --=20 2.35.1