From patchwork Mon Aug 19 19:09:22 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nathan Chancellor X-Patchwork-Id: 13768882 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 E372F26AD3; Mon, 19 Aug 2024 19:09:30 +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=1724094572; cv=none; b=EjVJs8S6g3rnAkS9OmGqEpo9G4UgwjVhipqPP0thyHyOnv+PNYmEfFIZDq5TLuopCBgGP/BdpTml5Sh+qa5AS1A5a+5VXo4mLOUm8mVkGVLr5EAIMirRfgFPLqoGX2/rEZY9U5aAQKOnfZOf4Z/Td/eFsIfvFGQrpY/CmWua8ec= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724094572; c=relaxed/simple; bh=l1fQ+yTpICnSE9dSKG3BDMX4w4n0NCxmJvBhJmEGqB4=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=YfmKR2vLYolwXbpssIP3hMZZMPEeluOd9BbKrl035u+OkzhFo6MH/X9ts4aXofWzqL9FYe06vrDqP87jrvFJ02sZUP1N656SOlDGnAFyhUv2e2zlTQEDqpURSLsgwrvK5LJ+w/2iG2EYcn2Dd1yrP6pXLnN9TaIl2E01l/ZRQlM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=K23Tcdhw; 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="K23Tcdhw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DA725C32782; Mon, 19 Aug 2024 19:09:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724094570; bh=l1fQ+yTpICnSE9dSKG3BDMX4w4n0NCxmJvBhJmEGqB4=; h=From:Date:Subject:To:Cc:From; b=K23Tcdhww1EkxB49+rm3W650EQEZDN1DZ4pOCr70a90bg1W+mWxNTIBGEWrzOsxdQ /EMvooiFf+IIqBl8ZSoQCK8gk7stYV/9fyjK02RANiVANd/6bgf7+Q5IrHJjrna605 3sfHSfexgVMRk/2N4SkoZbxhj8+tC6DqFIWHxeBXqQycXeOOgo/FgAXugNSB5QqnQd BGm7TQf7Psk8yCRfi2AJ47B1ggcOG9vOBhF0CqU7QPKErO3V2LFOMe5HDklGyEDSNZ eDL8qvPfw/Z5Alg22hFsgjYJiusCxk9w5Ue/Q5gJ7AZag2sYHD3Sl9TdjiH5tIFs9a 1v5qjV10mlL+A== From: Nathan Chancellor Date: Mon, 19 Aug 2024 12:09:22 -0700 Subject: [PATCH] ACPI: platform-profile: Fix CFI violation when accessing sysfs files Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240819-acpi-platform_profile-fix-cfi-violation-v1-1-479365d848f6@kernel.org> X-B4-Tracking: v=1; b=H4sIAGGYw2YC/x2N0QqDMAxFf0XyvIB2E52/Msbo2sQF1JZ0iCD+u 8HHw7mcu0MhFSowVDsorVIkLQbNrYLw88tIKNEYXO0edd880YcsmCf/56TzJ2timQhZNgwsuEo yZQ2M5Lq+a+/f2DJYLSvZ6Hp6vY/jBPDv3sd5AAAA To: "Rafael J. Wysocki" , Len Brown Cc: Hans de Goede , Mark Pearson , Kees Cook , Sami Tolvanen , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, patches@lists.linux.dev, stable@vger.kernel.org, John Rowley , Nathan Chancellor X-Mailer: b4 0.15-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=3849; i=nathan@kernel.org; h=from:subject:message-id; bh=l1fQ+yTpICnSE9dSKG3BDMX4w4n0NCxmJvBhJmEGqB4=; b=owGbwMvMwCUmm602sfCA1DTG02pJDGmHZ2T2TtC8LPzCnU3tVVZbYM1K5QeVO3XXH7z8tl5qm ZXRmVnrO0pZGMS4GGTFFFmqH6seNzScc5bxxqlJMHNYmUCGMHBxCsBEToQzMlzhUrrvE5x5tJHp V6pu56JiJXVdg/zMql8a0md81XYt+M/IsLj3AuOdt5MmRYmFBQg+OKRncsTvgeXsCesluSUjrvv P4AQA X-Developer-Key: i=nathan@kernel.org; a=openpgp; fpr=2437CB76E544CB6AB3D9DFD399739260CB6CB716 When an attribute group is created with sysfs_create_group(), the ->sysfs_ops() callback is set to kobj_sysfs_ops, which sets the ->show() and ->store() callbacks to kobj_attr_show() and kobj_attr_store() respectively. These functions use container_of() to get the respective callback from the passed attribute, meaning that these callbacks need to be the same type as the callbacks in 'struct kobj_attribute'. However, the platform_profile sysfs functions have the type of the ->show() and ->store() callbacks in 'struct device_attribute', which results a CFI violation when accessing platform_profile or platform_profile_choices under /sys/firmware/acpi because the types do not match: CFI failure at kobj_attr_show+0x19/0x30 (target: platform_profile_choices_show+0x0/0x140; expected type: 0x7a69590c) This happens to work because the layout of 'struct kobj_attribute' and 'struct device_attribute' are the same, so the container_of() cast happens to allow the callbacks to still work. Change the type of platform_profile_choices_show() and platform_profile_{show,store}() to match the callbacks in 'struct kobj_attribute' and update the attribute variables to match, which resolves the CFI violation. Cc: stable@vger.kernel.org Fixes: a2ff95e018f1 ("ACPI: platform: Add platform profile support") Reported-by: John Rowley Closes: https://github.com/ClangBuiltLinux/linux/issues/2047 Tested-by: John Rowley Signed-off-by: Nathan Chancellor Reviewed-by: Sami Tolvanen --- drivers/acpi/platform_profile.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) --- base-commit: 47ac09b91befbb6a235ab620c32af719f8208399 change-id: 20240819-acpi-platform_profile-fix-cfi-violation-de278753bd5f Best regards, diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c index d2f7fd7743a1..11278f785526 100644 --- a/drivers/acpi/platform_profile.c +++ b/drivers/acpi/platform_profile.c @@ -22,8 +22,8 @@ static const char * const profile_names[] = { }; static_assert(ARRAY_SIZE(profile_names) == PLATFORM_PROFILE_LAST); -static ssize_t platform_profile_choices_show(struct device *dev, - struct device_attribute *attr, +static ssize_t platform_profile_choices_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) { int len = 0; @@ -49,8 +49,8 @@ static ssize_t platform_profile_choices_show(struct device *dev, return len; } -static ssize_t platform_profile_show(struct device *dev, - struct device_attribute *attr, +static ssize_t platform_profile_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) { enum platform_profile_option profile = PLATFORM_PROFILE_BALANCED; @@ -77,8 +77,8 @@ static ssize_t platform_profile_show(struct device *dev, return sysfs_emit(buf, "%s\n", profile_names[profile]); } -static ssize_t platform_profile_store(struct device *dev, - struct device_attribute *attr, +static ssize_t platform_profile_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) { int err, i; @@ -115,12 +115,12 @@ static ssize_t platform_profile_store(struct device *dev, return count; } -static DEVICE_ATTR_RO(platform_profile_choices); -static DEVICE_ATTR_RW(platform_profile); +static struct kobj_attribute attr_platform_profile_choices = __ATTR_RO(platform_profile_choices); +static struct kobj_attribute attr_platform_profile = __ATTR_RW(platform_profile); static struct attribute *platform_profile_attrs[] = { - &dev_attr_platform_profile_choices.attr, - &dev_attr_platform_profile.attr, + &attr_platform_profile_choices.attr, + &attr_platform_profile.attr, NULL };