From patchwork Mon May 3 15:26:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guillaume Ranquet X-Patchwork-Id: 12236217 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9167FC433ED for ; Mon, 3 May 2021 15:26:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5E32E606A5 for ; Mon, 3 May 2021 15:26:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230426AbhECP11 (ORCPT ); Mon, 3 May 2021 11:27:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230401AbhECP1W (ORCPT ); Mon, 3 May 2021 11:27:22 -0400 Received: from mail-ot1-x32a.google.com (mail-ot1-x32a.google.com [IPv6:2607:f8b0:4864:20::32a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DE11C061763 for ; Mon, 3 May 2021 08:26:29 -0700 (PDT) Received: by mail-ot1-x32a.google.com with SMTP id b5-20020a9d5d050000b02902a5883b0f4bso5414818oti.2 for ; Mon, 03 May 2021 08:26:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20150623.gappssmtp.com; s=20150623; h=mime-version:from:date:message-id:subject:cc; bh=DsCC9gqqI3YCW9ovP0n+UcVOJC+7xZwxFoiL/RkkmZQ=; b=dTvWlgasNphbykbaGHMLyLlxm27D+XIBOlYNgL84vlKQzIt2kjc4Kpa53LEJlK56fH CfhhR/nv/DMZ2I5AUGXMjc4GWmsxBfA0tdkAV2H3leyucCOxjQHnq7nh3uGC8MLPG01f waYCxbw9lruqFE0t9nb6eIhAr0jK8vdtTLpyf8Smyux4w3GaYaegAA8OqvMev6QDvrsZ 4pRtlb4cXCcLWcnEVOL/Gr5Xf/XZM+GLQDWWPFsg6cKOSOdNiwgC8uV4kjIZeNNQIgJy Q+awveaVeyz4b4ewr4Iy8AariywFauLqvXNBeUKB5aSNAn51R5lMo3k/com9ahoxXTWE fm8g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:cc; bh=DsCC9gqqI3YCW9ovP0n+UcVOJC+7xZwxFoiL/RkkmZQ=; b=rvI00F2CwlAeLiHxcrGhK1Jib2VIebi9NxL79mUBvms6IIOcDW0hbY7FOCDSV8TzbQ fOa78fVxdo+RJjAk5CCNWWKHVMYvNdlgvQ3Yd3lPI8QxZ5aM4ypUsEJLDO/E0lFfCHgc RxgaHMwECutevCyXl/MRW26gIBMky8snQ4DQycY9I24hYpOkX81N/kgBBYqRqsqPKbZi Jng1P7HGE8N1vib7GShiBfxvWW3T5LVfTStN7DuEuFHY6h5/LJ0nxx3PE5wM6Stm0Usb Ci7QpvkJ32pPAFWALHoLvqSDgyELAy9J9nEbZxKx3DRLw3pQAj8r+RBZPkVe9nKCrzuh 36Iw== X-Gm-Message-State: AOAM5314GKOHDVc5d1jYvtk9Wq+IDZsbdx/E7iFfq20vfg4wpYaN31+2 JEHsM+MoN2p/zj/2MPvYhLEQlTKqRNphEyVpsd7eQg== MIME-Version: 1.0 X-Received: by 2002:a9d:2de3:: with SMTP id g90mt12928705otb.274.1620055588708; Mon, 03 May 2021 08:26:28 -0700 (PDT) Received: from 753933720722 named unknown by gmailapi.google.com with HTTPREST; Mon, 3 May 2021 08:26:27 -0700 From: Guillaume Ranquet Date: Mon, 3 May 2021 08:26:27 -0700 Message-ID: Subject: [PATCH 1/4] dmaengine: mediatek: free the proper desc in desc_free handler Cc: Sean Wang , Vinod Koul , Dan Williams , Matthias Brugger , dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org The desc_free handler assumed that the desc we want to free was always the current one associated with the channel. This is seldom the case and this is causing use after free crashes in multiple places (tx/rx/terminate...). BUG: KASAN: use-after-free in mtk_uart_apdma_rx_handler+0x120/0x304 Hardware name: GEA MT8167 ManeFaces (DT) Call trace: dump_backtrace+0x0/0x1b0 show_stack+0x24/0x34 dump_stack+0xe0/0x150 print_address_description+0x8c/0x55c __kasan_report+0x1b8/0x218 kasan_report+0x14/0x20 __asan_load4+0x98/0x9c mtk_uart_apdma_rx_handler+0x120/0x304 mtk_uart_apdma_irq_handler+0x50/0x80 __handle_irq_event_percpu+0xe0/0x210 handle_irq_event+0x8c/0x184 handle_fasteoi_irq+0x1d8/0x3ac __handle_domain_irq+0xb0/0x110 gic_handle_irq+0x50/0xb8 el0_irq_naked+0x60/0x6c Allocated by task 3541: __kasan_kmalloc+0xf0/0x1b0 kasan_kmalloc+0x10/0x1c kmem_cache_alloc_trace+0x90/0x2dc mtk_uart_apdma_prep_slave_sg+0x6c/0x1a0 mtk8250_dma_rx_complete+0x220/0x2e4 vchan_complete+0x290/0x340 tasklet_action_common+0x220/0x298 tasklet_action+0x28/0x34 __do_softirq+0x158/0x35c Freed by task 3541: __kasan_slab_free+0x154/0x224 kasan_slab_free+0x14/0x24 slab_free_freelist_hook+0xf8/0x15c kfree+0xb4/0x278 mtk_uart_apdma_desc_free+0x34/0x44 vchan_complete+0x1bc/0x340 tasklet_action_common+0x220/0x298 tasklet_action+0x28/0x34 __do_softirq+0x158/0x35c The buggy address belongs to the object at ffff000063606800 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 176 bytes inside of 256-byte region [ffff000063606800, ffff000063606900) The buggy address belongs to the page: page:fffffe00016d8180 refcount:1 mapcount:0 mapping:ffff00000302f600 index:0x0 compound_mapcount: 0 flags: 0xffff00000010200(slab|head) raw: 0ffff00000010200 dead000000000100 dead000000000122 ffff00000302f600 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Signed-off-by: Guillaume Ranquet static void mtk_uart_apdma_start_tx(struct mtk_chan *c) diff --git a/drivers/dma/mediatek/mtk-uart-apdma.c b/drivers/dma/mediatek/mtk-uart-apdma.c index 6bef40f0c9dc..4610dbdde75e 100644 --- a/drivers/dma/mediatek/mtk-uart-apdma.c +++ b/drivers/dma/mediatek/mtk-uart-apdma.c @@ -131,10 +131,7 @@ static unsigned int mtk_uart_apdma_read(struct mtk_chan *c, unsigned int reg) static void mtk_uart_apdma_desc_free(struct virt_dma_desc *vd) { - struct dma_chan *chan = vd->tx.chan; - struct mtk_chan *c = to_mtk_uart_apdma_chan(chan); - - kfree(c->desc); + kfree(container_of(vd, struct mtk_uart_apdma_desc, vd)); }