linux-kernel - [PATCH] x86: fix system die when load with "reservetop" parameter

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]

Date:	Thu, 20 Aug 2009 20:23:11 +0800
From:	Xiao Guangrong <xiaoguangrong@...fujitsu.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
CC:	Ingo Molnar <mingo@...e.hu>, yinghai@...nel.org,
	LKML <linux-kernel@...r.kernel.org>, x86@...nel.org
Subject: [PATCH] x86: fix system die when load with "reservetop" parameter

The system will die if the kernel is booted with "reservetop" parameter,
in present code, parse "reservetop" parameter after early_ioremap_init(),
and some function still use early_ioremap() after it.

The problem is, "reservetop" parameter can modify 'FIXADDR_TOP', then the
virtual address got by early_ioremap() is base on old 'FIXADDR_TOP', but
the page mapping is base on new 'FIXADDR_TOP', it will occur page fault,
and the IDT is not prepare yet, so, the system is dead.

So, put parse_early_param() in the front of early_ioremap_init() in this
patch.

Signed-off-by: Xiao Guangrong <xiaoguangrong@...fujitsu.com>
---
 arch/x86/kernel/setup.c |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 26fce55..aad6149 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -713,6 +713,11 @@ void __init setup_arch(char **cmdline_p)
 	printk(KERN_INFO "Command line: %s\n", boot_command_line);
 #endif
 
+	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
+	*cmdline_p = command_line;
+
+	parse_early_param();
+
 	/* VMI may relocate the fixmap; do this before touching ioremap area */
 	vmi_init();
 
@@ -795,11 +800,6 @@ void __init setup_arch(char **cmdline_p)
 #endif
 #endif
 
-	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
-	*cmdline_p = command_line;
-
-	parse_early_param();
-
 #ifdef CONFIG_X86_64
 	check_efer();
 #endif
-- 
1.6.1.2


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/