linux-kernel - [PATCH v3 4/4] x86/boot/64: Show original faulting address in case of error

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

Message-Id: <20201016200404.1615994-4-nivedita@alum.mit.edu>
Date:   Fri, 16 Oct 2020 16:04:04 -0400
From:   Arvind Sankar <nivedita@...m.mit.edu>
To:     Borislav Petkov <bp@...en8.de>
Cc:     x86@...nel.org, Joerg Roedel <jroedel@...e.de>,
        linux-kernel@...r.kernel.org
Subject: [PATCH v3 4/4] x86/boot/64: Show original faulting address in case of error

This makes the #PF handler print the original CR2 value in case of
error, instead of after aligning to PMD_SIZE.

Signed-off-by: Arvind Sankar <nivedita@...m.mit.edu>
Reviewed-by: Joerg Roedel <jroedel@...e.de>
---
 arch/x86/boot/compressed/ident_map_64.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c
index 06ebe5e3e489..505d6299b76e 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -333,9 +333,6 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code)
 
 	ghcb_fault = sev_es_check_ghcb_fault(address);
 
-	address   &= PMD_MASK;
-	end        = address + PMD_SIZE;
-
 	/*
 	 * Check for unexpected error codes. Unexpected are:
 	 *	- Faults on present pages
@@ -351,5 +348,8 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code)
 	 * Error code is sane - now identity map the 2M region around
 	 * the faulting address.
 	 */
+	address   &= PMD_MASK;
+	end        = address + PMD_SIZE;
+
 	add_identity_map(address, end);
 }
-- 
2.26.2