From patchwork Tue Jul 11 08:20:44 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 701619 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 E6CFDC0015E for ; Tue, 11 Jul 2023 08:20:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229843AbjGKIUy (ORCPT ); Tue, 11 Jul 2023 04:20:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41060 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229458AbjGKIUx (ORCPT ); Tue, 11 Jul 2023 04:20:53 -0400 Received: from mail-lj1-x229.google.com (mail-lj1-x229.google.com [IPv6:2a00:1450:4864:20::229]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 16D98E6A for ; Tue, 11 Jul 2023 01:20:52 -0700 (PDT) Received: by mail-lj1-x229.google.com with SMTP id 38308e7fff4ca-2b701e1c80fso81707131fa.2 for ; Tue, 11 Jul 2023 01:20:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1689063650; x=1691655650; h=in-reply-to:content-disposition:mime-version:message-id:subject:cc :to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=uTdlkhlpCCqeoNeoPuiVvBqr3VCWV64K8rIS7qqJISM=; b=IWXMcd8eMJHr2DIy2sik4O4IzCVH6d6WdfyrhNdgVX5cZbUrI5cCaR2wLh6sFSed9f qvv6vzMLbVvod6erYahZlnYthzzRtlvcbfwXuTe+4q4yiDc8UWTHkUTM91z3/6EaKTo3 Jojz0GrYbFS8r/1FuNya8qpOKYvw4Nl8JYsnnL4E7ocNL63wo0A4Vix/VUvKRvmQRb60 FRCKgJdm94SUGykkG5eYFkGDnvt2kHeSUgKeyMcyrYonFfuhp8xsmCDRF8v+RJmuOP0U 3JDHqt/ssETM1B1gB2VkWB/snbJCvsGy95uzDQzI37FWYbFfG0TmXAU+zTJ0YyQdyWdr AVHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689063650; x=1691655650; h=in-reply-to:content-disposition:mime-version:message-id:subject:cc :to:from:date:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=uTdlkhlpCCqeoNeoPuiVvBqr3VCWV64K8rIS7qqJISM=; b=j/ZHD5F9a6zfWB+MnFWL9Aw5oUs69VtdP65xW20sZYvIVsss8Yan3htJ21l5NrS9MC 1cgfqEzj0HXPcUo46gr074bUpUycgM3mQjbZvwR7Iw7VxyY9VFSIVbrL/FRzIURkKnkx L1L1996gNUYLXKovD7/G/SpYL0nf+dRkz9rkd9Yir0RZV1QRGCPu2+6GSHHUgCsFGbuj L8J8zLWpU76fPIYzY9eM1bT2EZ+Yuaziuw6/t4+RbH2NSLobth+DvnTGBixtWTja8zMs mkJj4Pyzo+/Y9GFS5qcpl35cSkoX/WqPZXOkcmFlzhjPjhQKFs4XHDdYq1e4Nk8RPRmM 3Q+Q== X-Gm-Message-State: ABy/qLYpcnJ713tWXlzIfE4Vw88m8gBCwWwWd6RqBpwjX3AEYbmUBCYa fTFt0mQHuhtNR/nU1fLnNXtZbOGmn9oT1KZXUI4= X-Google-Smtp-Source: APBJJlFAPzRYzDe1rsGW/YswGSAcORefT4bkbI9eiSkHF3c1m/SfcBojfmfiKAGoLNKbp/VdeGCmMQ== X-Received: by 2002:a2e:998e:0:b0:2b6:de63:6d3b with SMTP id w14-20020a2e998e000000b002b6de636d3bmr12672857lji.21.1689063650276; Tue, 11 Jul 2023 01:20:50 -0700 (PDT) Received: from localhost ([102.36.222.112]) by smtp.gmail.com with ESMTPSA id 12-20020a05600c020c00b003f819faff24sm12386039wmi.40.2023.07.11.01.20.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 11 Jul 2023 01:20:49 -0700 (PDT) Date: Tue, 11 Jul 2023 11:20:44 +0300 From: Dan Carpenter To: Jeffrey Hugo Cc: Carl Vanderlip , Pranjal Ramajor Asha Kanojiya , Oded Gabbay , Jacek Lawrynowicz , Stanislaw Gruszka , linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH 1/5 v4] accel/qaic: tighten bounds checking in encode_message() Message-ID: <9a0cb0c1-a974-4f10-bc8d-94437983639a@moroto.mountain> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <6e935c70-5bd2-4808-bdd9-d664f892b0b5@moroto.mountain> X-Mailer: git-send-email haha only kidding Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org There are several issues in this code. The check at the start of the loop: if (user_len >= user_msg->len) { This check does not ensure that we have enough space for the trans_hdr (8 bytes). Instead the check needs to be: if (user_len > user_msg->len - sizeof(*trans_hdr)) { That subtraction is done as an unsigned long we want to avoid negatives. Add a lower bound to the start of the function. if (user_msg->len < sizeof(*trans_hdr)) There is a second integer underflow which can happen if trans_hdr->len is zero inside the encode_passthrough() function. memcpy(out_trans->data, in_trans->data, in_trans->hdr.len - sizeof(in_trans->hdr)); Instead of adding a check to encode_passthrough() it's better to check in this central place. Add that check: if (trans_hdr->len < sizeof(trans_hdr) The final concern is that the "user_len + trans_hdr->len" might have an integer overflow bug. Use size_add() to prevent that. - if (user_len + trans_hdr->len > user_msg->len) { + if (size_add(user_len, trans_hdr->len) > user_msg->len) { Fixes: 129776ac2e38 ("accel/qaic: Add control path") Signed-off-by: Dan Carpenter Reviewed-by: Pranjal Ramajor Asha Kanojiya --- v4: send this patch. v2: * Fix the >= vs > bug in: if (user_len > user_msg->len - sizeof(*trans_hdr)) { * include overflow.h --- drivers/accel/qaic/qaic_control.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/accel/qaic/qaic_control.c b/drivers/accel/qaic/qaic_control.c index 5c57f7b4494e..2fdd5959c52f 100644 --- a/drivers/accel/qaic/qaic_control.c +++ b/drivers/accel/qaic/qaic_control.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -748,7 +749,8 @@ static int encode_message(struct qaic_device *qdev, struct manage_msg *user_msg, int ret; int i; - if (!user_msg->count) { + if (!user_msg->count || + user_msg->len < sizeof(*trans_hdr)) { ret = -EINVAL; goto out; } @@ -765,12 +767,13 @@ static int encode_message(struct qaic_device *qdev, struct manage_msg *user_msg, } for (i = 0; i < user_msg->count; ++i) { - if (user_len >= user_msg->len) { + if (user_len > user_msg->len - sizeof(*trans_hdr)) { ret = -EINVAL; break; } trans_hdr = (struct qaic_manage_trans_hdr *)(user_msg->data + user_len); - if (user_len + trans_hdr->len > user_msg->len) { + if (trans_hdr->len < sizeof(trans_hdr) || + size_add(user_len, trans_hdr->len) > user_msg->len) { ret = -EINVAL; break; } From patchwork Tue Jul 11 08:21:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 701618 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 1A49CC0015E for ; Tue, 11 Jul 2023 08:21:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230015AbjGKIVK (ORCPT ); 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Tue, 11 Jul 2023 01:21:04 -0700 (PDT) Date: Tue, 11 Jul 2023 11:21:00 +0300 From: Dan Carpenter To: Jeffrey Hugo Cc: Carl Vanderlip , Pranjal Ramajor Asha Kanojiya , Oded Gabbay , Jacek Lawrynowicz , Stanislaw Gruszka , linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, kernel-janitors@vger.kernel.org Subject: [PATCH 3/5 v4] accel/qaic: Add consistent integer overflow checks Message-ID: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <6e935c70-5bd2-4808-bdd9-d664f892b0b5@moroto.mountain> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The encode_dma() function has integer overflow checks. The encode_passthrough(), encode_activate() and encode_status() functions did not. I added integer overflow checking everywhere. I also updated the integer overflow checking in encode_dma() to use size_add() so everything is consistent. Fixes: 129776ac2e38 ("accel/qaic: Add control path") Signed-off-by: Dan Carpenter Reviewed-by: Pranjal Ramajor Asha Kanojiya --- v2: no change drivers/accel/qaic/qaic_control.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/accel/qaic/qaic_control.c b/drivers/accel/qaic/qaic_control.c index 752b67aff777..23680f5f1902 100644 --- a/drivers/accel/qaic/qaic_control.c +++ b/drivers/accel/qaic/qaic_control.c @@ -367,7 +367,7 @@ static int encode_passthrough(struct qaic_device *qdev, void *trans, struct wrap if (in_trans->hdr.len % 8 != 0) return -EINVAL; - if (msg_hdr_len + in_trans->hdr.len > QAIC_MANAGE_EXT_MSG_LENGTH) + if (size_add(msg_hdr_len, in_trans->hdr.len) > QAIC_MANAGE_EXT_MSG_LENGTH) return -ENOSPC; trans_wrapper = add_wrapper(wrappers, @@ -558,12 +558,10 @@ static int encode_dma(struct qaic_device *qdev, void *trans, struct wrapper_list msg = &wrapper->msg; msg_hdr_len = le32_to_cpu(msg->hdr.len); - if (msg_hdr_len > (UINT_MAX - QAIC_MANAGE_EXT_MSG_LENGTH)) - return -EINVAL; - /* There should be enough space to hold at least one ASP entry. */ - if (msg_hdr_len + sizeof(*out_trans) + sizeof(struct wire_addr_size_pair) > - QAIC_MANAGE_EXT_MSG_LENGTH) + if (size_add(msg_hdr_len, + sizeof(*out_trans) + sizeof(struct wire_addr_size_pair)) > + QAIC_MANAGE_EXT_MSG_LENGTH) return -ENOMEM; if (in_trans->addr + in_trans->size < in_trans->addr || !in_trans->size) @@ -635,7 +633,7 @@ static int encode_activate(struct qaic_device *qdev, void *trans, struct wrapper msg = &wrapper->msg; msg_hdr_len = le32_to_cpu(msg->hdr.len); - if (msg_hdr_len + sizeof(*out_trans) > QAIC_MANAGE_MAX_MSG_LENGTH) + if (size_add(msg_hdr_len, sizeof(*out_trans)) > QAIC_MANAGE_MAX_MSG_LENGTH) return -ENOSPC; if (!in_trans->queue_size) @@ -719,7 +717,7 @@ static int encode_status(struct qaic_device *qdev, void *trans, struct wrapper_l msg = &wrapper->msg; msg_hdr_len = le32_to_cpu(msg->hdr.len); - if (msg_hdr_len + in_trans->hdr.len > QAIC_MANAGE_MAX_MSG_LENGTH) + if (size_add(msg_hdr_len, in_trans->hdr.len) > QAIC_MANAGE_MAX_MSG_LENGTH) return -ENOSPC; trans_wrapper = add_wrapper(wrappers, sizeof(*trans_wrapper)); From patchwork Tue Jul 11 08:21:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 701617 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 5A725C0015E for ; Tue, 11 Jul 2023 08:21:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230148AbjGKIVV (ORCPT ); Tue, 11 Jul 2023 04:21:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41482 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229573AbjGKIVU (ORCPT ); Tue, 11 Jul 2023 04:21:20 -0400 Received: from mail-wm1-x32c.google.com (mail-wm1-x32c.google.com [IPv6:2a00:1450:4864:20::32c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 337209C for ; 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Call put_page() on the pages before returning. Fixes: 129776ac2e38 ("accel/qaic: Add control path") Signed-off-by: Dan Carpenter Reviewed-by: Pranjal Ramajor Asha Kanojiya --- no change drivers/accel/qaic/qaic_control.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/accel/qaic/qaic_control.c b/drivers/accel/qaic/qaic_control.c index d5ce36cb351f..9a6f80f31c65 100644 --- a/drivers/accel/qaic/qaic_control.c +++ b/drivers/accel/qaic/qaic_control.c @@ -425,9 +425,12 @@ static int find_and_map_user_pages(struct qaic_device *qdev, } ret = get_user_pages_fast(xfer_start_addr, nr_pages, 0, page_list); - if (ret < 0 || ret != nr_pages) { - ret = -EFAULT; + if (ret < 0) goto free_page_list; + if (ret != nr_pages) { + nr_pages = ret; + ret = -EFAULT; + goto put_pages; } sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);