From patchwork Sun Mar 26 16:52:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Elder X-Patchwork-Id: 13188359 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 381D9C6FD1C for ; Sun, 26 Mar 2023 16:52:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232093AbjCZQwc (ORCPT ); Sun, 26 Mar 2023 12:52:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229621AbjCZQwb (ORCPT ); Sun, 26 Mar 2023 12:52:31 -0400 Received: from mail-io1-xd2a.google.com (mail-io1-xd2a.google.com [IPv6:2607:f8b0:4864:20::d2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4256F4EEF for ; Sun, 26 Mar 2023 09:52:30 -0700 (PDT) Received: by mail-io1-xd2a.google.com with SMTP id d14so2896511ion.9 for ; Sun, 26 Mar 2023 09:52:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1679849548; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=uZDpfx3urFpkn6ahCSfHgrhA7mhIEUMUgAQsnqLHf8E=; b=lw02E4M5hD/bCTsw9aoEmp9o5Go8WICBB/nja5f64DrIyDY6COPKylxnqlVBtpfdyv GWv5TcbfKlbtBJ+sfHmTSiLAUCwSjT3IZ4gqsSTUwupt8zpbAKCRjRKbx5EDmtHx9Jg7 wZQeuVT7Y8KrQsCY4h8XRNw9l/iNZSG1avD3eld/z7UqgI3lHJx1EwL95+lC7vdqxed9 h3cH/8oyD191x2pTz/cgAism5FJUp+2gFb3N2ECBaOXcIqggZjF+I96gjnrReKF8tDe+ juVli4JRKwUMK6stG0/4Hgfw8oPz0jI3NlEB55ZijzDxTp2ToJEgyy+4tsofGkZ86Zgx 6rVQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679849548; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=uZDpfx3urFpkn6ahCSfHgrhA7mhIEUMUgAQsnqLHf8E=; b=r2Xo7qglEpPBTTkjoeANh/ijb9Rs5hnI4HXl5KWIDpMgEY3qP+AIMRxiTuFtbwX09v u0w0sctT8lhfJuRFEQr5WqBXp8vwEAdHe4hDwthvB/pjjkRWRojdq40NreRGmotXUI6Y qFOcmRZ0q34uXdOnLnUoYWVhDDgjPUOEUXbQ1AQMd4fnVlFl1+ZcVEtM5hOT5quQiEs4 W1GZRmAjgxUl7OdRubmObOAC8jb7SCMcxSPGZttrTb3HK7iPZx5EdUTQjuJL0devjJLa Q6gTNfE1FhfrQ4Qjuo0H4VN0Y5Xgfq22H2q9fSvmWeXo77Fm8f8E/xi0jVANrwpsxBvM b6Qw== X-Gm-Message-State: AO0yUKXesm44OCzkE+PIQnivLOtKs+XGUBHBYLLLxTsYS7kB3pQ9NH64 ZM805gil2l4t0GNZKM8WEg95rA== X-Google-Smtp-Source: AK7set99/fu0tVXo6FiX13qhaEmHEvLC3MCJvfjzz3kDAiKDyyxTs7GgLGQPJFXfM9JXlMm2u5od7w== X-Received: by 2002:a6b:f707:0:b0:74c:7db1:47cf with SMTP id k7-20020a6bf707000000b0074c7db147cfmr6914684iog.14.1679849548663; Sun, 26 Mar 2023 09:52:28 -0700 (PDT) Received: from localhost.localdomain ([98.61.227.136]) by smtp.gmail.com with ESMTPSA id s10-20020a6bdc0a000000b0074e7960e70dsm3675834ioc.51.2023.03.26.09.52.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 26 Mar 2023 09:52:27 -0700 (PDT) From: Alex Elder To: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com Cc: quic_bjorande@quicinc.com, caleb.connolly@linaro.org, mka@chromium.org, evgreen@chromium.org, andersson@kernel.org, quic_cpratapa@quicinc.com, quic_avuyyuru@quicinc.com, quic_jponduru@quicinc.com, quic_subashab@quicinc.com, elder@kernel.org, netdev@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH net] net: ipa: compute DMA pool size properly Date: Sun, 26 Mar 2023 11:52:23 -0500 Message-Id: <20230326165223.2707557-1-elder@linaro.org> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org In gsi_trans_pool_init_dma(), the total size of a pool of memory used for DMA transactions is calculated. However the calculation is done incorrectly. For 4KB pages, this total size is currently always more than one page, and as a result, the calculation produces a positive (though incorrect) total size. The code still works in this case; we just end up with fewer DMA pool entries than we intended. Bjorn Andersson tested booting a kernel with 16KB pages, and hit a null pointer derereference in sg_alloc_append_table_from_pages(), descending from gsi_trans_pool_init_dma(). The cause of this was that a 16KB total size was going to be allocated, and with 16KB pages the order of that allocation is 0. The total_size calculation yielded 0, which eventually led to the crash. Correcting the total_size calculation fixes the problem. Reported-by: Tested-by: Fixes: 9dd441e4ed57 ("soc: qcom: ipa: GSI transactions") Signed-off-by: Alex Elder Reviewed-by: Mark Bloch --- drivers/net/ipa/gsi_trans.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ipa/gsi_trans.c b/drivers/net/ipa/gsi_trans.c index 0f52c068c46d6..ee6fb00b71eb6 100644 --- a/drivers/net/ipa/gsi_trans.c +++ b/drivers/net/ipa/gsi_trans.c @@ -156,7 +156,7 @@ int gsi_trans_pool_init_dma(struct device *dev, struct gsi_trans_pool *pool, * gsi_trans_pool_exit_dma() can assume the total allocated * size is exactly (count * size). */ - total_size = get_order(total_size) << PAGE_SHIFT; + total_size = PAGE_SIZE << get_order(total_size); virt = dma_alloc_coherent(dev, total_size, &addr, GFP_KERNEL); if (!virt)