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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DC518C54F4C for ; Tue, 28 Jul 2026 13:08:46 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CE9E06B009F; Tue, 28 Jul 2026 09:08:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C9C0C6B00A0; Tue, 28 Jul 2026 09:08:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B89E56B00A1; Tue, 28 Jul 2026 09:08:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 8E0B46B009F for ; Tue, 28 Jul 2026 09:08:45 -0400 (EDT) Received: from smtpin03.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 1F9CB80394 for ; Tue, 28 Jul 2026 13:08:45 +0000 (UTC) X-FDA: 85038215010.03.417FD5B Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf01.hostedemail.com (Postfix) with ESMTP id 7049440002 for ; Tue, 28 Jul 2026 13:08:43 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=jarQQNfZ; spf=pass (imf01.hostedemail.com: domain of rppt@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1785244123; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=3sxlim6Jm3YtcLECKKEooguzj3UphetqkoUwty9M5B0=; b=B7XQRC4Jqjfzjd51+hSJtdhV0LhymxWu5v3fPNwKh0K9gDiWXSGBRlZX8H0uriVKK6ragX BLVjLT9aP5N2GFkOV/tqz2yvr2jVySg6VAbXcbKqujJ3IBbjk7rS+QDwN+lKbDqqOxH7Ld Cdi2PVzUd1KeCNHFWlyMzR/q1v3KuCg= ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1785244123; b=m7TradyuDX2hH2F2JIlpzSCeAve9X2inarIZ+LyvpvUs67td+s4qc9R5+3xJfYhB22P7D4 xIIa3pQc1WJNEy5DTOSINgrq+dy6f2KFlmav7v0J+TvRKLY1ZopYDDOJUjrLFKBPlOo1Qi Hm8xwg984bmH9vcsOEW4fMbGDi0V5/c= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=jarQQNfZ; spf=pass (imf01.hostedemail.com: domain of rppt@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 1215D60AA9; Tue, 28 Jul 2026 13:08:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 87B051F000E9; Tue, 28 Jul 2026 13:08:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785244122; bh=3sxlim6Jm3YtcLECKKEooguzj3UphetqkoUwty9M5B0=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=jarQQNfZ22qSDtdYLOxTo6gp1glpSKTDMwZLTumpSpou4pkARWfxuXW0DuYezdnxI 55l6PTEocmVCk9K6xmlrSUHC2LEsxlHfleAW0kpx5eyjBAjehHSRdwr4qAw3a8N2UW up1JsYO0nEFjLX0TKB96knGccON9uyl9aMGQ+rm52v5U0Cbul/sAhSc4py+kIKozAm myeiesn/+aSopbFgd2lqsMXmU00rMXpXPFzh5qU1gPmmtJ1/F+xaMy8mvMSlHXWScB uV4spMcQaPfqHEYQqNvv4Lz3lbxD5/HYN0H8ZYaoAJf39wAxREkcJrXY4XFGPMWCo1 wp1qoELYYdhvQ== From: "Mike Rapoport (Microsoft)" Date: Tue, 28 Jul 2026 16:07:48 +0300 Subject: [PATCH 5/5] x86/mm/pat: fix effective RW computation in lookup_address_in_pgd_attr() MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260728-cpa-fixes-v1-5-2ed2352300b3@kernel.org> References: <20260728-cpa-fixes-v1-0-2ed2352300b3@kernel.org> In-Reply-To: <20260728-cpa-fixes-v1-0-2ed2352300b3@kernel.org> To: Dave Hansen Cc: Andrew Morton , Andy Lutomirski , Borislav Petkov , David CARLIER , David Hildenbrand , Ingo Molnar , Jason Gunthorpe , Juergen Gross , Kevin Tian , Kiryl Shutsemau , "Liam R. Howlett" , Lorenzo Stoakes , Lu Baolu , Mike Rapoport , "H. Peter Anvin" , Peter Zijlstra , Shakeel Butt , Suren Baghdasaryan , Thomas Gleixner , Toshi Kani , Vishal Moola , Vlastimil Babka , Will Deacon , iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org, x86@kernel.org, syzbot@syzkaller.appspotmail.com X-Mailer: b4 0.16-dev X-Rspamd-Queue-Id: 7049440002 X-Stat-Signature: xpgx8qgy1h1oznkbotubyat34ha4m9in X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1785244123-341501 X-HE-Meta: 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 9DuYYOer IMDPysZ6Mb/3SrVHxC4bcgUpjDMQq9N8RB8kC1VK/MzdpRdIbQSOLVpPaUsUBaYTnSsxq6pTfJ6Vs6yDnr+n+ZpeCDs5sX4NvliCrGObtt7kdMoL2P8zhL9bJjhWergl0/mau4do5wQ5khrdPLgnzZlocKLeo9m03tJnsudqZgEZYG9n/4IfHyl0/+d3pspxsb5L6enAjplZwnvaepsFaQsujJ1D1SZJESNsayjOc8umiWWUK39oWU7BCj60I3k9o8p57dKIt6q79zh2DzhswFKY2GiuwOo8Apo/rL0L0QZv8yQ6NqTOkn7gXs4DeVO69JN3AF2fQfLa3uR3IY9kCraDwH3FPEI9TzNaRF0ihr15oY2DFvBGO3I0iM0d43NZKc1C5dROjawzEq68fitrtc1ozQlNrMh5n+879id4ELUnOu/EapXeQ20TPUb/8Ln5iHVSL2YAJeAkPvlE/e10G4jL5xqiepw0JJ7ai9/YZQbB7LP0= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: lookup_address_in_pgd_attr() accumulates the effective NX and RW bits of the walked page table levels so that verify_rwx() can detect mappings that are both writable and executable. The RW bits are folded into a bool with rw &= pXd_flags(*pXd) & _PAGE_RW; but _PAGE_RW is 0x2. So consider the accumulation line: rw &= pXd_flags(*pXd) & _PAGE_RW; where rw=0x1 and the right side evaluates down to 0x2. It'll end up doing: rw = 0x1 & 0x2 and rw always ends up 0. This way rw becomes false at the first level walked, regardless of the actual permissions, and verify_rwx() treats every mapping as non-writable and never reports a W^X violation. Add double negation to the right side to normalize the _PAGE_RW flag to 0 or 1. Fixes: ceb647b4b529 ("x86/pat: Introduce lookup_address_in_pgd_attr()") Cc: stable@vger.kernel.org Assisted-by: Copilot:claude-opus-4.8 Reviewed-by: Juergen Gross Tested-by: syzbot@syzkaller.appspotmail.com Signed-off-by: Mike Rapoport (Microsoft) --- arch/x86/mm/pat/set_memory.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index 1b63d4caba20..7d656520887c 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -769,7 +769,7 @@ pte_t *lookup_address_in_pgd_attr(pgd_t *pgd, unsigned long address, *level = PG_LEVEL_512G; *nx |= pgd_flags(*pgd) & _PAGE_NX; - *rw &= pgd_flags(*pgd) & _PAGE_RW; + *rw &= !!(pgd_flags(*pgd) & _PAGE_RW); p4d = p4d_offset(pgd, address); if (p4d_none(*p4d)) @@ -780,7 +780,7 @@ pte_t *lookup_address_in_pgd_attr(pgd_t *pgd, unsigned long address, *level = PG_LEVEL_1G; *nx |= p4d_flags(*p4d) & _PAGE_NX; - *rw &= p4d_flags(*p4d) & _PAGE_RW; + *rw &= !!(p4d_flags(*p4d) & _PAGE_RW); pud = pud_offset(p4d, address); if (pud_none(*pud)) @@ -791,7 +791,7 @@ pte_t *lookup_address_in_pgd_attr(pgd_t *pgd, unsigned long address, *level = PG_LEVEL_2M; *nx |= pud_flags(*pud) & _PAGE_NX; - *rw &= pud_flags(*pud) & _PAGE_RW; + *rw &= !!(pud_flags(*pud) & _PAGE_RW); pmd = pmd_offset(pud, address); if (pmd_none(*pmd)) @@ -802,7 +802,7 @@ pte_t *lookup_address_in_pgd_attr(pgd_t *pgd, unsigned long address, *level = PG_LEVEL_4K; *nx |= pmd_flags(*pmd) & _PAGE_NX; - *rw &= pmd_flags(*pmd) & _PAGE_RW; + *rw &= !!(pmd_flags(*pmd) & _PAGE_RW); return pte_offset_kernel(pmd, address); } -- 2.53.0