From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f45.google.com (mail-pj1-f45.google.com [209.85.216.45]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4BB593F6C55 for ; Mon, 13 Jul 2026 12:11:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.45 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783944715; cv=none; b=Bd0+UjH3YHjpNuP0baiSVAbne/4CBhGYOnfDtXT0Fs1dv47GA4+MpG/PpNVOFXSpnkHqEYOHtYhYLCe9ogMFCUnWHtCQSEzCjg4J//ebJK847J6nVGySO/neUyTSDfMO1a0JFkjYckjphzCTexfvUXZSBxZ08ua3+FWggcp9I7U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783944715; c=relaxed/simple; bh=ptkcLZC/rZ3ISEyM/x91NL/C1Etf2/yRncxk30AlMs0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QaZpjAJnVcePcs90aUYAK5YIuZrcKZVQpt+rSQWj35UlLT5nRBsmePcGkEQd2Hj8zI4pAF6TLG+DnhJeLEtgvseRJIoll6/T+pWt+UuO+wxk2721btd+8lF55HhYQbqy41Q1qZB/1HECNsw1NBamHdqfzTFBHv7Q8xX8BRCkLyo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=PjOEqM4o; arc=none smtp.client-ip=209.85.216.45 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="PjOEqM4o" Received: by mail-pj1-f45.google.com with SMTP id 98e67ed59e1d1-38dc69c74b8so1491841a91.0 for ; Mon, 13 Jul 2026 05:11:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1783944714; x=1784549514; darn=vger.kernel.org; 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:content-type; bh=M8Fc1y4+RwjniJfgwRtIk0X9ABaeOzCopsCGLc1zspc=; b=PjOEqM4o0ovCqKiaFjVJqWCJuuV52AYTqcRtlAQKII5bEone2chz6L8trltPCyiVBE Ky6SzkltMCBjlmmvQwgdYzyTbz5/o566wdNMqeVUThx0jsoZ5KZsoa9HwrQ1uuW0AvZv MRZ9Xaj2NQoViPTRh0aqYe057dUQ/0J28AoBf8+boowUuo3ydhhxZ14M9x/ngp8K3li9 OsUL10czxNdEHr75rUzuQxlC3mrZNAHOqKfSrXvJMi1scas3gY5NXz7V3MGyTv7zFBD2 fuIU3VcJXBpvhnZPgQF4yjNy0f1ah688qtByKTDbCFYmNrmB9INUZ8iVLwbBiplXdNpq MoCQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1783944714; x=1784549514; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=M8Fc1y4+RwjniJfgwRtIk0X9ABaeOzCopsCGLc1zspc=; b=hihP56yY2nEzxMhoBg10G0c04tTaGdcL5jwT6N2xtm2P3fAfdG2ummLSRodZkR2TPf 3WCl65jCJm/hYURvVmMcJ6xstu78JYYIpFvTeY4yYXKDrevZZ6HS5MNv5a+PBFggLrNN NJKZO+1LG0jlKUY8jk9pPP1w88vRngs0RIU8hY+W/OCRjfDaIBHWeXgE8luay9XDXQ8I 0KjG2pBG0/Kh3pakTbIEvrYN+MICPqxbubHSydU5VRNTSRM+7YnafBqzYCnDbOmR4jA5 sGNhVEcr/JKnPMroBJuWVZE6DIXDz4bX/srXf95TsfxdsGiQSVX/zQqUdD1uJy5t5eS0 Lozg== X-Forwarded-Encrypted: i=1; AHgh+Rr/HxmRor3agUUfOggvvo2AM5hlNdLBve4Fc6AfchlxESr6FmrH2xoOYwJa/gBMCcRwzAgvJMmMJlO0dug=@vger.kernel.org X-Gm-Message-State: AOJu0YzWE5gOZ49waPZaVnybBd7K21nYVloqaL1O75pOAzyoEz4SkRZP TwW8C3GXcZrFsOq6insudPe/1tR5GxaqC3lE81kXURKMs+/YUvb3O9Jm X-Gm-Gg: AfdE7clbvN5oWfLvCZO85YIdaahBXT6qHyt5KmWDm5f53yzk3kHCYyIH8hVqCoKBBhm CMCyPR+2obqsSDWv33grg7CMXEyo7cNWtHEPVa8SiuHQrcM3rt61PkSkQllne/Fd+eKvnjXHkRS 8docRSzGnXXm2tPEZQlsGaF2pcNz8scKN1TChSFWTQCq9SbOGo0NIJNQHPQettRTSEoN/ZTSCl8 5kBxJ/hv3wyNO+k1/rIJOWWixGlkPP/0Kbta+o56JKGPOIux1zhhhnb5uu7JDmXBpMXlNheuKtV 2f/ovzUQG83s6/TdOHxfKF+zVhZECaLNn/gUus8e1pre7O79tWZjDicc+dORI0M5DZPyU02n4uG 83mHNncCLkLacokPIexomt8UkMYKEFyrKi+BuK+vuNx7hZ7YvbDMp9T1trdk2POxjGttA1KJMtH //MbPbWexl1g== X-Received: by 2002:a17:90b:4c51:b0:37c:607b:2cd9 with SMTP id 98e67ed59e1d1-38dc7607589mr7644160a91.0.1783944713757; Mon, 13 Jul 2026 05:11:53 -0700 (PDT) Received: from rockpi-5b ([45.112.0.180]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-311747f7293sm67756935eec.3.2026.07.13.05.11.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Jul 2026 05:11:53 -0700 (PDT) From: Anand Moon To: Neil Armstrong , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Kevin Hilman , Jerome Brunet , Martin Blumenstingl , Mauro Carvalho Chehab , Greg Kroah-Hartman , dri-devel@lists.freedesktop.org (open list:DRM DRIVERS FOR AMLOGIC SOCS), linux-amlogic@lists.infradead.org (open list:DRM DRIVERS FOR AMLOGIC SOCS), linux-arm-kernel@lists.infradead.org (moderated list:ARM/Amlogic Meson SoC support), linux-kernel@vger.kernel.org (open list), linux-media@vger.kernel.org (open list:MESON VIDEO DECODER DRIVER FOR AMLOGIC SOCS), linux-staging@lists.linux.dev (open list:STAGING SUBSYSTEM) Cc: Anand Moon , Doruk Tan Ozturk , Nicolas Dufresne , Sashiko Subject: [PATCH v7 17/19] media: meson: canvas: Fix Use-After-Free by linking canvas provider device Date: Mon, 13 Jul 2026 17:37:12 +0530 Message-ID: <20260713120840.17427-18-linux.amoon@gmail.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20260713120840.17427-1-linux.amoon@gmail.com> References: <20260713120840.17427-1-linux.amoon@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The vdec driver retrieves a canvas instance using meson_canvas_get() and stores the raw pointer in core->canvas. However, the helper drops the provider device reference via put_device() right before returning. Because no formal device relationship is established, an unbind of the canvas provider driver triggers a Use-After-Free (UAF) bug when the video decoder subsequently attempts to access that memory block. Fix this lifecycle hazard by enhancing meson_canvas_get() to establish a formal managed device link between the consumer device and the underlying canvas platform device. Using DL_FLAG_AUTOREMOVE_CONSUMER ensures the dependency link is automatically torn down when the consumer driver unbinds. Additionally, handle missing link conditions using dev_err_probe() to clean up upstream error diagnostics, and ensure the canvas platform device reference count is dropped safely along the uninitialized driver data path. Cc: Nicolas Dufresne Reported-by: Sashiko Closes: https://lore.kernel.org/all/20260530111022.9C6D71F00893@smtp.kernel.org Signed-off-by: Anand Moon --- drivers/soc/amlogic/meson-canvas.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/soc/amlogic/meson-canvas.c b/drivers/soc/amlogic/meson-canvas.c index 79681afea8c61..5102a491bf778 100644 --- a/drivers/soc/amlogic/meson-canvas.c +++ b/drivers/soc/amlogic/meson-canvas.c @@ -54,6 +54,7 @@ struct meson_canvas *meson_canvas_get(struct device *dev) struct device_node *canvas_node; struct platform_device *canvas_pdev; struct meson_canvas *canvas; + struct device_link *link; canvas_node = of_parse_phandle(dev->of_node, "amlogic,canvas", 0); if (!canvas_node) @@ -70,9 +71,18 @@ struct meson_canvas *meson_canvas_get(struct device *dev) * current state, this driver probe cannot return -EPROBE_DEFER */ canvas = dev_get_drvdata(&canvas_pdev->dev); - put_device(&canvas_pdev->dev); - if (!canvas) + if (!canvas) { + put_device(&canvas_pdev->dev); return ERR_PTR(-EINVAL); + } + + /* Establish device link to prevent Use-After-Free */ + link = device_link_add(dev, &canvas_pdev->dev, + DL_FLAG_AUTOREMOVE_CONSUMER); + put_device(&canvas_pdev->dev); + if (!link) + return ERR_PTR(dev_err_probe(dev, -EINVAL, + "Failed to create device link canvas\n")); return canvas; } -- 2.50.1