linux-kernel - [PATCH 19/19] UML - Physical memory shouldn't include initial stack

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>] [day] [month] [year] [list]

Message-ID: <20080425175618.GA11208@c2.user-mode-linux.org>
Date:	Fri, 25 Apr 2008 13:56:18 -0400
From:	Jeff Dike <jdike@...toit.com>
To:	Andrew Morton <akpm@...l.org>, LKML <linux-kernel@...r.kernel.org>,
	uml-devel <user-mode-linux-devel@...ts.sourceforge.net>
Cc:	"Christopher S. Aker" <caker@...shore.net>
Subject: [PATCH 19/19] UML - Physical memory shouldn't include initial stack

The top of physical memory should be below the initial process stack,
not the top of the address space, at least for as long as the stack
isn't known to the kernel VM system and appropriately reserved.

Cc: "Christopher S. Aker" <caker@...shore.net>
Signed-off-by: Jeff Dike <jdike@...ux.intel.com>
---
 arch/um/kernel/um_arch.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Index: linux-2.6-git/arch/um/kernel/um_arch.c
===================================================================
--- linux-2.6-git.orig/arch/um/kernel/um_arch.c	2008-04-24 15:16:52.000000000 -0400
+++ linux-2.6-git/arch/um/kernel/um_arch.c	2008-04-24 16:04:52.000000000 -0400
@@ -258,6 +258,7 @@ int __init linux_main(int argc, char **a
 {
 	unsigned long avail, diff;
 	unsigned long virtmem_size, max_physmem;
+	unsigned long stack;
 	unsigned int i, add;
 	char * mode;
 
@@ -347,7 +348,9 @@ int __init linux_main(int argc, char **a
 	}
 
 	virtmem_size = physmem_size;
-	avail = TASK_SIZE - start_vm;
+	stack = (unsigned long) argv;
+	stack &= ~(1024 * 1024 - 1);
+	avail = stack - start_vm;
 	if (physmem_size > avail)
 		virtmem_size = avail;
 	end_vm = start_vm + virtmem_size;
--
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/