From mboxrd@z Thu Jan 1 00:00:00 1970 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 39F7BC4332F for ; Thu, 24 Nov 2022 17:50:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229739AbiKXRuC (ORCPT ); Thu, 24 Nov 2022 12:50:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42938 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229504AbiKXRty (ORCPT ); Thu, 24 Nov 2022 12:49:54 -0500 Received: from mail-wr1-x435.google.com (mail-wr1-x435.google.com [IPv6:2a00:1450:4864:20::435]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D50914A2EB for ; Thu, 24 Nov 2022 09:49:49 -0800 (PST) Received: by mail-wr1-x435.google.com with SMTP id x5so3459424wrt.7 for ; Thu, 24 Nov 2022 09:49:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=WnrDbdRJkbksqZItXruR6kyL5+sqtubhQgH9dDxfehQ=; b=xoMkl3EeeMJyo2ElRyotEqbHF4q3toa1fIBVElAPlmfzfxIlN/Tv9nzrFEvqKil4U/ T75C7W15kUrJq4v5/Pp6sX+DBu/0JPFeMJE04JZ0B8+1qRZkB74QFhAfJu5fQpuMLsg2 NG15tCUEQrlJI+1nTxOou0+jKdYTrAdqzZJOEgc1r5sMNasBL/fbyfIRDVQtVyVrpxxp AmwszvnbzSEqM2HkdCprCvHXGKr8ZH4y7QeTTjJNynOcy3ezTJtZVTfc3lrNqUCFSMoF l765G/f21FSHhFSMS984AihwFVeebbBXbkIfHYV59Lch5+Gn3B6BUAbGu5rLbXl1F7wm D8jQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=WnrDbdRJkbksqZItXruR6kyL5+sqtubhQgH9dDxfehQ=; b=mnVCSLw8rQ4keoJMScOGohluU/WMOlRXl94NfnuX/qjjG4IG+ea7+dHwstu+R89m5g XIZ/HuwhlWqpIJ/WqKavG/oDFJaa3U+/9ztQ57uTuth4qcOWXO2AOLhLK4PJrWHghp0g 3yMosvXIZYc1eL6CoxWTro5ZCZ9OFKCyUwiwQk1IZxzoVTvG3/iSl0P9l5ciHKYciWBF tXP/4mkffY2lScYtZ5V1vuzscssGL3vrxE3RXEsRBekyBeIBGyjg3ViLiAdkcL5ippnc JinTb/0S9KKWiZ1nhD2HjHrNcrx9v5cooDvtimP6Y827ZH/SsabGGNTcXTUWCDISyqVf io6Q== X-Gm-Message-State: ANoB5pnDhMnArzJ2dkWuhLu7wk5lvFZ+Lna7QUoG56Ye/D5WFI8b9dkx t2MKxKhjb5g65/nXw0TMoX1dow== X-Google-Smtp-Source: AA0mqf6zIsKV2cNw5MNIc5hWrXSQbLgOgCA06wPURrAvGy4D6Zu6D4mui3Y6CpYaH4oDMecauRctqw== X-Received: by 2002:a5d:6b46:0:b0:236:56a6:823e with SMTP id x6-20020a5d6b46000000b0023656a6823emr20762122wrw.495.1669312188150; Thu, 24 Nov 2022 09:49:48 -0800 (PST) Received: from localhost.localdomain ([5.133.47.210]) by smtp.gmail.com with ESMTPSA id l11-20020a1c790b000000b003b4a699ce8esm6250863wme.6.2022.11.24.09.49.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 24 Nov 2022 09:49:47 -0800 (PST) From: Srinivas Kandagatla To: gregkh@linuxfoundation.org Cc: linux-kernel@vger.kernel.org, Abel Vesa , Ola Jeppsson , Srinivas Kandagatla Subject: [PATCH 2/3] misc: fastrpc: Don't remove map on creater_process and device_release Date: Thu, 24 Nov 2022 17:49:40 +0000 Message-Id: <20221124174941.418450-3-srinivas.kandagatla@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221124174941.418450-1-srinivas.kandagatla@linaro.org> References: <20221124174941.418450-1-srinivas.kandagatla@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Abel Vesa Do not remove the map from the list on error path in fastrpc_init_create_process, instead call fastrpc_map_put, to avoid use-after-free. Do not remove it on fastrpc_device_release either, call fastrpc_map_put instead. The fastrpc_free_map is the only proper place to remove the map. This is called only after the reference count is 0. Fixes: b49f6d83e290 ("misc: fastrpc: Fix a possible double free") Co-developed-by: Ola Jeppsson Signed-off-by: Ola Jeppsson Signed-off-by: Abel Vesa Signed-off-by: Srinivas Kandagatla --- drivers/misc/fastrpc.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c index fc2173c59f8b..9ecbf673d321 100644 --- a/drivers/misc/fastrpc.c +++ b/drivers/misc/fastrpc.c @@ -316,6 +316,13 @@ static void fastrpc_free_map(struct kref *ref) dma_buf_put(map->buf); } + if (map->fl) { + spin_lock(&map->fl->lock); + list_del(&map->node); + spin_unlock(&map->fl->lock); + map->fl = NULL; + } + kfree(map); } @@ -1266,12 +1273,7 @@ static int fastrpc_init_create_process(struct fastrpc_user *fl, fl->init_mem = NULL; fastrpc_buf_free(imem); err_alloc: - if (map) { - spin_lock(&fl->lock); - list_del(&map->node); - spin_unlock(&fl->lock); - fastrpc_map_put(map); - } + fastrpc_map_put(map); err: kfree(args); @@ -1347,10 +1349,8 @@ static int fastrpc_device_release(struct inode *inode, struct file *file) fastrpc_context_put(ctx); } - list_for_each_entry_safe(map, m, &fl->maps, node) { - list_del(&map->node); + list_for_each_entry_safe(map, m, &fl->maps, node) fastrpc_map_put(map); - } list_for_each_entry_safe(buf, b, &fl->mmaps, node) { list_del(&buf->node); -- 2.25.1