From: Jan Beulich <jbeulich@novell.com>
Date: Sat, 21 Jul 2007 15:10:21 +0000 (+0200)
Subject: i386: allow debuggers to access the vsyscall page with compat vDSO
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=2f30c00702aca3229e1157718675f0ee56d2a931;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

i386: allow debuggers to access the vsyscall page with compat vDSO

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/arch/i386/kernel/sysenter.c b/arch/i386/kernel/sysenter.c
index ff4ee6f3326b..6deb159d08e0 100644
--- a/arch/i386/kernel/sysenter.c
+++ b/arch/i386/kernel/sysenter.c
@@ -336,7 +336,9 @@ struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
 
 int in_gate_area(struct task_struct *task, unsigned long addr)
 {
-	return 0;
+	const struct vm_area_struct *vma = get_gate_vma(task);
+
+	return vma && addr >= vma->vm_start && addr < vma->vm_end;
 }
 
 int in_gate_area_no_task(unsigned long addr)