From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 937DECCA47B for ; Fri, 10 Jun 2022 23:36:55 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4LKcn20dwBz3dQJ for ; Sat, 11 Jun 2022 09:36:54 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=Du1hwDz4; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=intel.com (client-ip=134.134.136.24; helo=mga09.intel.com; envelope-from=ira.weiny@intel.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=Du1hwDz4; dkim-atps=neutral Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4LKclg4fkNz3brd for ; Sat, 11 Jun 2022 09:35:42 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1654904143; x=1686440143; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=E0S7lAVxIGr1gPnTIVSUeXKWXCH1YKeQN7klBTJ1vLE=; b=Du1hwDz4O4Pbao+KCYxLbOm02gHBA/Q0EIpiQOsPyyJeg23DqldjzMB5 xgSOp6czBX3qu7PcRztbODCYfqPTH/IyfY9g+3Krz76TXsNqQGAC59yAR idxwFWVFnJ60e+Lf/U01PRBotIuCY3+wOhR8acJHkaMVwYhbQwIFmvp9l k1WDE82UKH3ys060e4sT6JTsGrftSb243u1zQ2eBe0IxL2EXHfknxHHFX UqHm5uxfvecqP7TM57dP2AyaiwIWQg6NmNuYIboLg4ROfbLUb9cXjFoDS 1JTIYdNO3m++QSXKXfVTsMF83o+DEKLvtaxp9GCqIwkUs0CGTCBxdnCt0 g==; X-IronPort-AV: E=McAfee;i="6400,9594,10374"; a="278579385" X-IronPort-AV: E=Sophos;i="5.91,291,1647327600"; d="scan'208";a="278579385" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Jun 2022 16:35:40 -0700 X-IronPort-AV: E=Sophos;i="5.91,291,1647327600"; d="scan'208";a="909166943" Received: from pleung-mobl1.amr.corp.intel.com (HELO localhost) ([10.212.33.34]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Jun 2022 16:35:40 -0700 From: ira.weiny@intel.com To: linux-api@vger.kernel.org Subject: [RFC PATCH 5/6] pkeys: Up level pkey_free() checks Date: Fri, 10 Jun 2022 16:35:32 -0700 Message-Id: <20220610233533.3649584-6-ira.weiny@intel.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220610233533.3649584-1-ira.weiny@intel.com> References: <20220610233533.3649584-1-ira.weiny@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Florian Weimer , x86@kernel.org, clemensb@chromium.org, jkummerow@chromium.org, "Aneesh Kumar K . V" , Dave Hansen , linuxppc-dev@lists.ozlabs.org, ahaas@chromium.org, linux-kernel@vger.kernel.org, gdeepti@chromium.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, Sohil Mehta , Andrew Morton , Ira Weiny , manoskouk@chromium.org, thibaudm@chromium.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Ira Weiny x86 is missing a hardware check for pkey support in pkey_free(). While the net result is the same (-EINVAL returned), pkey_free() has well defined behavior which will be easier to maintain in one place. For powerpc the return code is -1 rather than -EINVAL. This changes that behavior slightly but this is very unlikely to break any user space. Lift the checks for pkey_free() to the core mm code and ensure consistency with returning -EINVAL. Cc: ahaas@chromium.org Cc: clemensb@chromium.org Cc: gdeepti@chromium.org Cc: jkummerow@chromium.org Cc: manoskouk@chromium.org Cc: thibaudm@chromium.org Cc: Florian Weimer Cc: Andrew Morton Cc: linux-api@vger.kernel.org Cc: Sohil Mehta Cc: Dave Hansen Cc: Aneesh Kumar K.V Signed-off-by: Ira Weiny --- Thanks to Sohil for suggesting I mention the powerpc return value in the commit message. Also Sohil suggested changing mm_pkey_free() from int to void. This is added as a separate patch with his suggested by. --- arch/powerpc/include/asm/pkeys.h | 6 ------ arch/x86/include/asm/pkeys.h | 3 --- mm/mprotect.c | 8 ++++++-- 3 files changed, 6 insertions(+), 11 deletions(-) diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h index 2c8351248793..e96aa91f817b 100644 --- a/arch/powerpc/include/asm/pkeys.h +++ b/arch/powerpc/include/asm/pkeys.h @@ -107,12 +107,6 @@ static inline int mm_pkey_alloc(struct mm_struct *mm) static inline int mm_pkey_free(struct mm_struct *mm, int pkey) { - if (!mmu_has_feature(MMU_FTR_PKEY)) - return -1; - - if (!mm_pkey_is_allocated(mm, pkey)) - return -EINVAL; - __mm_pkey_free(mm, pkey); return 0; diff --git a/arch/x86/include/asm/pkeys.h b/arch/x86/include/asm/pkeys.h index 2e6c04d8a45b..da02737cc4d1 100644 --- a/arch/x86/include/asm/pkeys.h +++ b/arch/x86/include/asm/pkeys.h @@ -107,9 +107,6 @@ int mm_pkey_alloc(struct mm_struct *mm) static inline int mm_pkey_free(struct mm_struct *mm, int pkey) { - if (!mm_pkey_is_allocated(mm, pkey)) - return -EINVAL; - mm_set_pkey_free(mm, pkey); return 0; diff --git a/mm/mprotect.c b/mm/mprotect.c index 56d35de33725..41458e729c27 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -803,10 +803,14 @@ SYSCALL_DEFINE2(pkey_alloc, unsigned long, flags, unsigned long, init_val) SYSCALL_DEFINE1(pkey_free, int, pkey) { - int ret; + int ret = -EINVAL; + + if (!arch_pkeys_enabled()) + return ret; mmap_write_lock(current->mm); - ret = mm_pkey_free(current->mm, pkey); + if (mm_pkey_is_allocated(current->mm, pkey)) + ret = mm_pkey_free(current->mm, pkey); mmap_write_unlock(current->mm); /* -- 2.35.1