linux-kernel - [tip: x86/urgent] x86/mm: Fix pti_clone_entry

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <172250973153.2215.13116668336106656424.tip-bot2@tip-bot2>
Date: Thu, 01 Aug 2024 10:55:31 -0000
From: "tip-bot2 for Peter Zijlstra" <tip-bot2@...utronix.de>
To: linux-tip-commits@...r.kernel.org
Cc: "Peter Zijlstra (Intel)" <peterz@...radead.org>, x86@...nel.org,
 linux-kernel@...r.kernel.org
Subject: [tip: x86/urgent] x86/mm: Fix pti_clone_entry_text() for i386

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID:     49947e7aedfea2573bada0c95b85f6c2363bef9f
Gitweb:        https://git.kernel.org/tip/49947e7aedfea2573bada0c95b85f6c2363bef9f
Author:        Peter Zijlstra <peterz@...radead.org>
AuthorDate:    Thu, 01 Aug 2024 12:42:25 +02:00
Committer:     Peter Zijlstra <peterz@...radead.org>
CommitterDate: Thu, 01 Aug 2024 12:48:23 +02:00

x86/mm: Fix pti_clone_entry_text() for i386

While x86_64 has PMD aligned text sections, i386 does not have this
luxery. Notably ALIGN_ENTRY_TEXT_END is empty and _etext has PAGE
alignment.

This means that text on i386 can be page granular at the tail end,
which in turn means that the PTI text clones should consistently
account for this.

Make pti_clone_entry_text() consistent with pti_clone_kernel_text().

Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
---
 arch/x86/mm/pti.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c
index 48c5032..bfdf5f4 100644
--- a/arch/x86/mm/pti.c
+++ b/arch/x86/mm/pti.c
@@ -496,7 +496,7 @@ static void pti_clone_entry_text(void)
 {
 	pti_clone_pgtable((unsigned long) __entry_text_start,
 			  (unsigned long) __entry_text_end,
-			  PTI_CLONE_PMD);
+			  PTI_LEVEL_KERNEL_IMAGE);
 }
 
 /*