From patchwork Wed Jul 8 03:25:18 2026 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hongling Zeng X-Patchwork-Id: 2593 Return-Path: X-Original-To: noreply@patchwork.local Delivered-To: noreply@patchwork.local Received: from sea.lore.kernel.org (sea.lore.kernel.org [172.234.253.10]) by mxe881.netcup.net (Postfix) with ESMTPS id 908E71C3FFC for ; Wed, 8 Jul 2026 05:25:34 +0200 (CEST) Authentication-Results: mxe881; spf=pass (sender IP is 172.234.253.10) smtp.mailfrom=linux-sunxi+bounces-24274-noreply=patchwork.local@lists.linux.dev smtp.helo=sea.lore.kernel.org Received-SPF: pass (mxe881: domain of lists.linux.dev designates 172.234.253.10 as permitted sender) client-ip=172.234.253.10; envelope-from=linux-sunxi+bounces-24274-noreply=patchwork.local@lists.linux.dev; helo=sea.lore.kernel.org; Received: from smtp.subspace.kernel.org (conduit.subspace.kernel.org [100.90.174.1]) by sea.lore.kernel.org (Postfix) with ESMTP id 92F19301A3BA for ; Wed, 8 Jul 2026 03:25:32 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 3298A34D911; Wed, 8 Jul 2026 03:25:32 +0000 (UTC) X-Original-To: linux-sunxi@lists.linux.dev Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 227EE1F8755 for ; Wed, 8 Jul 2026 03:25:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783481132; cv=none; b=QKrMT5nZRl9RGbUXXCAXSS5hXvFWqq4kL47fdufAnXBtAeLszBdyYwecKMU2slydlbr1g1gGj1xhygdwFroLIyPRELfgoUXlK+f6ctMXbB0Ml8h5ElJ97tp/28P8mwiym8h/CcZHF2Oks83fR+sL+AHyh+gAkinjEBhx/VGSDXU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783481132; c=relaxed/simple; bh=S/EDF6i4+4ttv2+aNfJOupl/XYk3+PNv+SiacfMdla4=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=LYsYbQG8xlK8pR07h0iBonCrIWIiFUt3ys6N4M4FI5kqtwchZdz7hwlITibDoTx71tA9KFPL3jJPgz4yuTN5FqDcr4B5pNzh8EohhIqOsjj4PHcuW9H/2NmzJiKWnxULg2qz4w7GEnms1VWOOGhK55XZCig7yhYxl4oxQ9X6k/Y= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: a7e407fa7a7c11f1aa26b74ffac11d73-20260708 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.12,REQID:ae684cea-d52f-46d5-a2f7-460587711f77,IP:0,U RL:0,TC:0,Content:0,EDM:-25,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:-25 X-CID-META: VersionHash:e7bac3a,CLOUDID:164c4e05a8185255933934eb70240207,BulkI D:nil,BulkQuantity:0,Recheck:0,SF:102|850|865|898,TC:nil,Content:0|15|50,E DM:2,IP:nil,URL:0,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA: 0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: a7e407fa7a7c11f1aa26b74ffac11d73-20260708 X-User: zenghongling@kylinos.cn Received: from localhost.localdomain [(10.44.16.150)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 1092104708; Wed, 08 Jul 2026 11:25:23 +0800 From: Hongling Zeng To: vkoul@kernel.org, Frank.Li@kernel.org, wens@kernel.org, jernej.skrabec@gmail.com, samuel@sholland.org, mripard@kernel.org, arnd@arndb.de Cc: dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev, linux-kernel@vger.kernel.org, zhongling0719@126.com, Hongling Zeng Subject: [PATCH v4] dmaengine: sun6i-dma: Fix use-after-free in error handling paths Date: Wed, 8 Jul 2026 11:25:18 +0800 Message-Id: <20260708032518.50886-1-zenghongling@kylinos.cn> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-sunxi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MORS-Enabled: yes X-MORS-DOMAIN: patchwork.local X-MORS-HOSTING: hosting172546 X-MORS-USER: hosting172546 X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= In error handling paths, the for loop frees v_lli in the loop body, then accesses v_lli->v_lli_next and v_lli->p_lli_next in the increment expression, which is use-after-free. Fix by saving both the next virtual and physical pointers before freeing the current node. Fixes: 555859308723 ("dmaengine: Add driver for Allwinner sun6i DMA") Signed-off-by: Hongling Zeng Suggested-by: Jernej Skrabec Reviewed-by: Jernej Skrabec --- Changes in v2: -Refactored the fix to avoid code duplication by creating a helper function sun6i_dma_free_lli_list() that handles LLI list cleanup -Add Suggested-by: Jernej Skrabec --- Change in v3: -Further refactoring to move txd handling into the helper function as suggested by Jernej --- Change in v4: -Add reviewed-by --- drivers/dma/sun6i-dma.c | 31 ++++++++++++++++--------------- 1 file changed, 16 insertions(+), 15 deletions(-) diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c index fcc88a74d821..e161fc298b86 100644 --- a/drivers/dma/sun6i-dma.c +++ b/drivers/dma/sun6i-dma.c @@ -406,16 +406,12 @@ static inline void sun6i_dma_dump_lli(struct sun6i_vchan *vchan, v_lli->len, v_lli->para, v_lli->p_lli_next); } -static void sun6i_dma_free_desc(struct virt_dma_desc *vd) +static void sun6i_dma_free_desc(struct sun6i_dma_dev *sdev, + struct sun6i_desc *txd) { - struct sun6i_desc *txd = to_sun6i_desc(&vd->tx); - struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vd->tx.chan->device); struct sun6i_dma_lli *v_lli, *v_next; dma_addr_t p_lli, p_next; - if (unlikely(!txd)) - return; - p_lli = txd->p_lli; v_lli = txd->v_lli; @@ -432,6 +428,17 @@ static void sun6i_dma_free_desc(struct virt_dma_desc *vd) kfree(txd); } +static void sun6i_dma_free_desc_virt(struct virt_dma_desc *vd) +{ + struct sun6i_desc *txd = to_sun6i_desc(&vd->tx); + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vd->tx.chan->device); + + if (unlikely(!txd)) + return; + + sun6i_dma_free_desc(sdev, txd); +} + static int sun6i_dma_start_desc(struct sun6i_vchan *vchan) { struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vchan->vc.chan.device); @@ -788,10 +795,7 @@ static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg( return vchan_tx_prep(&vchan->vc, &txd->vd, flags); err_lli_free: - for (p_lli = txd->p_lli, v_lli = txd->v_lli; v_lli; - p_lli = v_lli->p_lli_next, v_lli = v_lli->v_lli_next) - dma_pool_free(sdev->pool, v_lli, p_lli); - kfree(txd); + sun6i_dma_free_desc(sdev, txd); return NULL; } @@ -869,10 +873,7 @@ static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_cyclic( return vchan_tx_prep(&vchan->vc, &txd->vd, flags); err_lli_free: - for (p_lli = txd->p_lli, v_lli = txd->v_lli; v_lli; - p_lli = v_lli->p_lli_next, v_lli = v_lli->v_lli_next) - dma_pool_free(sdev->pool, v_lli, p_lli); - kfree(txd); + sun6i_dma_free_desc(sdev, txd); return NULL; } @@ -1432,7 +1433,7 @@ static int sun6i_dma_probe(struct platform_device *pdev) struct sun6i_vchan *vchan = &sdc->vchans[i]; INIT_LIST_HEAD(&vchan->node); - vchan->vc.desc_free = sun6i_dma_free_desc; + vchan->vc.desc_free = sun6i_dma_free_desc_virt; vchan_init(&vchan->vc, &sdc->slave); }