From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.17]) (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 C41EB45DF72; Tue, 4 Aug 2026 13:38:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.17 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785850713; cv=none; b=N4Ipyp5B6LhavRJLZgn+uiir71CuvxvYDnhHN3eB9aEW19psyPXYdyK2sxOuSo/okL5adCuZm/u7/pX0ICTqVjK9Q6A5ij0ex0q7Ag5BHwWkZMw+a7Jb083+wQ+nXb7MC/s0JOOSMwxFzuIvXa/krjzgQjS+CO4TFvPN/aBZLQg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785850713; c=relaxed/simple; bh=LKC0QMMd/XJevryXpaROjCj9xdLCE4mgoSSaTfBGOkw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EZx2XcGvFWzqzXLjTVXeSmIrGmJF+qncuvcuJsVcmvdeIhPJw8sj0bf+GICDHKTpKB6ZTQTP0oEqYJsnylq8DElSvQZEiNBs6Yk+qH9LbcPc62nqRnHiONCIJ4R0SUWNd1INQ8ogIIHlo6IzCwOCNgpR4H8bgr+wiWWz80TOzpc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=NVv3AVg3; arc=none smtp.client-ip=198.175.65.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="NVv3AVg3" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1785850712; x=1817386712; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=LKC0QMMd/XJevryXpaROjCj9xdLCE4mgoSSaTfBGOkw=; b=NVv3AVg3e020crnsEVP2jDT8vB5YIOaltOYi+WYpApzckqZLuk90BNN5 uKn+NMvTuDaTG8qWRppQbwHCKdCUL2Q5SUQPvrVbmPwhQ1Da69QpkDpEb qXPpNmmORWYQwjmL2+qzsMdYC02LfvBud9p9wgFPXNrpwzJZQ9NAr0+O+ MGij1/Feo9crgpltPbgx3XutyQZRGdgOIfcJ66CbD7WW6TwGUTlIjakAL hojtu6BSFceVhIxwBse+vj8UkwHI94FhqnlEWJNjTjmINetkYMjkFjCv8 XiC6g0DdGcwliMdVm5aka12PyvKSXfnbicP+YLP7RIAIyDESBdVHRqxJc A==; X-CSE-ConnectionGUID: bXxopzvwTFG42jhZpfI2fw== X-CSE-MsgGUID: u+MdLMfkR2q46ewddF89nA== X-IronPort-AV: E=McAfee;i="6800,10657,11864"; a="86410104" X-IronPort-AV: E=Sophos;i="6.25,204,1779174000"; d="scan'208";a="86410104" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by orvoesa109.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Aug 2026 06:38:31 -0700 X-CSE-ConnectionGUID: YYbXWcnOQa6ckgQl8WVVmQ== X-CSE-MsgGUID: uFswiDBTSTqxPCk+c6eisw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,204,1779174000"; d="scan'208";a="263501013" Received: from mkosciow-mobl1.ger.corp.intel.com (HELO ahunter6-desk) ([10.245.245.132]) by fmviesa004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Aug 2026 06:38:29 -0700 From: Adrian Hunter To: alexandre.belloni@bootlin.com Cc: Frank.Li@nxp.com, akhilrajeev@nvidia.com, rafael@kernel.org, linux-i3c@lists.infradead.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-pm@vger.kernel.org Subject: [PATCH V3 04/14] i3c: master: Fix use-after-free of master->this Date: Tue, 4 Aug 2026 16:38:00 +0300 Message-ID: <20260804133810.184905-5-adrian.hunter@intel.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260804133810.184905-1-adrian.hunter@intel.com> References: <20260804133810.184905-1-adrian.hunter@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Organization: Intel Finland Oy, Registered Address: c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Content-Transfer-Encoding: 8bit sysfs attribute callbacks for the master controller device dereference master->this. However, master->this is currently freed in i3c_master_detach_free_devs(), before the master device itself is released. As a result, sysfs accesses can dereference a freed master->this pointer, leading to a use-after-free. Keep master->this alive until i3c_masterdev_release(), where all users of the master device have gone away and the associated sysfs state is being torn down. Do not free master->this as part of the normal device detach path. Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure") Cc: stable@vger.kernel.org Signed-off-by: Adrian Hunter --- Changes in V3: New patch drivers/i3c/master.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c index abb582645a2e..4839c1c186eb 100644 --- a/drivers/i3c/master.c +++ b/drivers/i3c/master.c @@ -842,6 +842,11 @@ static struct attribute *i3c_masterdev_attrs[] = { }; ATTRIBUTE_GROUPS(i3c_masterdev); +static void i3c_master_free_i3c_dev(struct i3c_dev_desc *dev) +{ + kfree(dev); +} + static void i3c_masterdev_release(struct device *dev) { struct i3c_master_controller *master = dev_to_i3cmaster(dev); @@ -854,6 +859,8 @@ static void i3c_masterdev_release(struct device *dev) i3c_bus_cleanup(bus); fwnode_handle_put(dev->fwnode); + + i3c_master_free_i3c_dev(master->this); } static const struct device_type i3c_masterdev_type = { @@ -1125,11 +1132,6 @@ static void i3c_device_release(struct device *dev) kfree(i3cdev); } -static void i3c_master_free_i3c_dev(struct i3c_dev_desc *dev) -{ - kfree(dev); -} - static struct i3c_dev_desc * i3c_master_alloc_i3c_dev(struct i3c_master_controller *master, const struct i3c_device_info *info) @@ -2286,7 +2288,8 @@ static void i3c_master_detach_free_devs(struct i3c_master_controller *master) i3cdev->boardinfo->init_dyn_addr, I3C_ADDR_SLOT_FREE); - i3c_master_free_i3c_dev(i3cdev); + if (i3cdev != master->this) + i3c_master_free_i3c_dev(i3cdev); } list_for_each_entry_safe(i2cdev, i2ctmp, &master->bus.devs.i2c, -- 2.53.0