From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 6C7613CEBBC; Mon, 27 Apr 2026 13:59:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777298369; cv=none; b=DRQ3bQ0/sbZCKonYBJ4M+o4uzWVKYWIwWGCOlD3CQRtJaR/VacjbwL98biKPEUeKkXCM2pvyYR/9JUXdi3x+79/BYAdlZHlF2OmSR1luK9/M9K5QmaXNuqeHOh60Ib+3Rv8nuVGnmIvbs9DcF2zGsl9nvVrAH3TA9hpGnyOvwDQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777298369; c=relaxed/simple; bh=lLNZlNo4AbW+zXp5BcjsajFSNEqcY1uPQqOOFXgHf0Y=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=C2CuRO1l3FwNRBWgYI1xDzzIM6qvde2reUpntrTn+Jk1AkulZDU86BBl3HC8uBvD77VwVqt9RwrNbtTGQ9amfWcDpJbze0+dPEfWa/o1MBTd3Cg7ASp1FMkGnJa0Gx5Y1AVdb8S6qU3EzF7vVJ7Lt1e5504aPBJSfdqSuSjRKSs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=sfvN5dqc; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="sfvN5dqc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70E6FC2BCB4; Mon, 27 Apr 2026 13:59:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777298369; bh=lLNZlNo4AbW+zXp5BcjsajFSNEqcY1uPQqOOFXgHf0Y=; h=From:To:Cc:Subject:Date:From; b=sfvN5dqcc6cm3QEMsdLfkDDeKgf6mSl7DHBeNFFfoF860jJv6fyK7RuGx1q1VaZYS 1sr6cm43dF+xsp1/6F5JCdoitdq57Gh+agORN5+QdUY39fjkJ3LSZlt0Su/5AqhQ0u Fw98dgry7KVEfexzcKj0EKsbJVRjs/Wybm/Y2ydDn4plXuZwKIxpa6J0NzLmcRrM4X 28IFzIdJgRsNjkCtD7Vd1yGrEmLu/moUPgkZyOvD6VmqWIzwuWmuP5FiSXU6Ev5zJS nux/tYpMncLAx3rondyRmEUghb/15fwe4ShgDPASKgNJR+si+tUEdGcD0Y+2E8QK28 TVkyIAbcZeqJA== From: Tzung-Bi Shih To: Arnd Bergmann , Greg Kroah-Hartman , Bartosz Golaszewski , Linus Walleij Cc: Benson Leung , tzungbi@kernel.org, linux-kernel@vger.kernel.org, chrome-platform@lists.linux.dev, driver-core@lists.linux.dev, linux-doc@vger.kernel.org, linux-gpio@vger.kernel.org, "Rafael J. Wysocki" , Danilo Krummrich , Jonathan Corbet , Shuah Khan , Laurent Pinchart , Wolfram Sang , Jason Gunthorpe , Johan Hovold , "Paul E . McKenney" , Dan Williams Subject: [PATCH v9 0/9] drivers/base: Introduce revocable Date: Mon, 27 Apr 2026 21:58:32 +0800 Message-ID: <20260427135841.96266-1-tzungbi@kernel.org> X-Mailer: git-send-email 2.51.0 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This series introduces the "revocable" mechanism, a synchronization primitive designed to prevent Use-After-Free errors. - Patch 1 introduces the revocable which is an implementation of ideas from the talk [1]. - Patch 2 adds KUnit test cases. - Patches 3 to 7 transitions the UAF prevention logic within the GPIO core (gpiolib) to use the "revocable" mechanism. The existing code aims to prevent UAF issues when the underlying GPIO chip is removed. They replace that custom logic with the generic "revocable" API, which is designed to handle such lifecycle dependencies. There should be no changes in behavior. - Patches 8 to 9 uses "revocable" mechanism to fix an UAF in cros_ec_chardev driver. Alternatively, [2] is a series for fixing the same issue without using "revocable". Since v9, there are two ways to manage the resource provider handle. - Embedded allocation: patches 3 to 7 might be the potential user. - Dynamic allocation: patches 8 to 9 might be the potential user. [1] https://lpc.events/event/17/contributions/1627/ [2] https://lore.kernel.org/all/20260427134659.95181-1-tzungbi@kernel.org --- v9: - Rebase onto v7.1-rc1. - Remove the selftests patch as it makes less sense to test revocable APIs via kselftests. - Merge patches 7 to 11 from https://lore.kernel.org/all/20260213092958.864411-1-tzungbi@kernel.org into the series. - Merge patch from https://lore.kernel.org/all/20250923075302.591026-5-tzungbi@kernel.org - Merge patch from https://lore.kernel.org/all/20250912081718.3827390-6-tzungbi@kernel.org v8: https://lore.kernel.org/all/20260213092307.858908-1-tzungbi@kernel.org - Rework on the revocable APIs. See changelog in [PATCH v8 1/3] for details. v7: https://lore.kernel.org/all/20260116080235.350305-1-tzungbi@kernel.org - Rebase onto next-20260115. v6: https://lore.kernel.org/all/20251106152330.11733-1-tzungbi@kernel.org - Rebase onto next-20251106. - Separate revocable core and use cases. v5: https://lore.kernel.org/all/20251016054204.1523139-1-tzungbi@kernel.org - Rebase onto next-20251015. - Add more context about the PoC. - Support multiple revocable providers in the PoC. v4: https://lore.kernel.org/all/20250923075302.591026-1-tzungbi@kernel.org - Rebase onto next-20250922. - Remove the 5th patch from v3. - Add fops replacement PoC in 5th - 7th patches. v3: https://lore.kernel.org/all/20250912081718.3827390-1-tzungbi@kernel.org - Rebase onto https://lore.kernel.org/all/20250828083601.856083-1-tzungbi@kernel.org and next-20250912. - The 4th patch changed accordingly. v2: https://lore.kernel.org/all/20250820081645.847919-1-tzungbi@kernel.org - Rename "ref_proxy" -> "revocable". - Add test cases in Kunit and selftest. v1: https://lore.kernel.org/all/20250814091020.1302888-1-tzungbi@kernel.org Tzung-Bi Shih (9): revocable: Revocable resource management revocable: Add KUnit test cases gpio: Add revocable provider handle for struct gpio_chip gpio: cdev: Leverage revocable for accessing struct gpio_chip gpio: Remove gpio_chip_guard by using revocable gpio: Leverage revocable for accessing struct gpio_chip gpio: Remove unused `chip` and `srcu` in struct gpio_device platform/chrome: Protect cros_ec_device lifecycle with revocable platform/chrome: cros_ec_chardev: Consume cros_ec_device via revocable .../driver-api/driver-model/index.rst | 1 + .../driver-api/driver-model/revocable.rst | 384 +++++++++++++++ MAINTAINERS | 10 + drivers/base/Kconfig | 5 + drivers/base/Makefile | 5 +- drivers/base/revocable.c | 298 +++++++++++ drivers/base/revocable_test.c | 461 ++++++++++++++++++ drivers/gpio/gpiolib-cdev.c | 77 ++- drivers/gpio/gpiolib-sysfs.c | 31 +- drivers/gpio/gpiolib.c | 255 ++++------ drivers/gpio/gpiolib.h | 28 +- drivers/platform/chrome/cros_ec.c | 11 + drivers/platform/chrome/cros_ec_chardev.c | 80 ++- include/linux/platform_data/cros_ec_proto.h | 3 + include/linux/revocable.h | 214 ++++++++ 15 files changed, 1597 insertions(+), 266 deletions(-) create mode 100644 Documentation/driver-api/driver-model/revocable.rst create mode 100644 drivers/base/revocable.c create mode 100644 drivers/base/revocable_test.c create mode 100644 include/linux/revocable.h -- 2.51.0