pve-kernel-lowlatency-qoup/patches/kernel/0103-x86-entry-32-Fix-cpu_current_top_of_stack-initializa.patch
2018-01-07 13:18:22 +01:00

52 lines
2.0 KiB
Diff

From 870277eb767ecec9293c5dd5ba5bf1c912251e85 Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@kernel.org>
Date: Thu, 2 Nov 2017 00:59:15 -0700
Subject: [PATCH 103/233] x86/entry/32: Fix cpu_current_top_of_stack
initialization at boot
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
CVE-2017-5754
cpu_current_top_of_stack's initialization forgot about
TOP_OF_KERNEL_STACK_PADDING. This bug didn't matter because the
idle threads never enter user mode.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/e5e370a7e6e4fddd1c4e4cf619765d96bb874b21.1509609304.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit cd493a6deb8b78eca280d05f7fa73fd69403ae29)
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
(cherry picked from commit 258c98e7d4b8f1459772e656cd736c028a13add9)
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
---
arch/x86/kernel/smpboot.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index d05006f6c31c..8ea3b18cbdc1 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -961,8 +961,7 @@ void common_cpu_up(unsigned int cpu, struct task_struct *idle)
#ifdef CONFIG_X86_32
/* Stack for startup_32 can be just as for start_secondary onwards */
irq_ctx_init(cpu);
- per_cpu(cpu_current_top_of_stack, cpu) =
- (unsigned long)task_stack_page(idle) + THREAD_SIZE;
+ per_cpu(cpu_current_top_of_stack, cpu) = task_top_of_stack(idle);
#else
initial_gs = per_cpu_offset(cpu);
#endif
--
2.14.2