From 19af4c06d3e7e8c839a1d6ff80d822851172bbd8 Mon Sep 17 00:00:00 2001
From: Chuck Ebbert <76306.1226@compuserve.com>
Date: Mon, 26 Jun 2006 13:59:50 +0200
Subject: [PATCH] --- yaml --- r: 30523 b: refs/heads/master c:
 03fdc2c277afdbd217eccd1ce0cfeff77ebd8b77 h: refs/heads/master i:   30521:
 edd3215c1b88012c0cd63138bed59c867faeb975   30519:
 9f9fe4a7c4a898957ca8343b3374df2248ddbc85 v: v3

---
 [refs]                       | 2 +-
 trunk/arch/x86_64/mm/fault.c | 6 ++++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 4242efd94810..f074d263525f 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6bfa9bb5195c68f75bd3937e4d77cb0bfe852d0d
+refs/heads/master: 03fdc2c277afdbd217eccd1ce0cfeff77ebd8b77
diff --git a/trunk/arch/x86_64/mm/fault.c b/trunk/arch/x86_64/mm/fault.c
index 64728898f869..4968a71df4aa 100644
--- a/trunk/arch/x86_64/mm/fault.c
+++ b/trunk/arch/x86_64/mm/fault.c
@@ -410,8 +410,10 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
 	if (!(vma->vm_flags & VM_GROWSDOWN))
 		goto bad_area;
 	if (error_code & 4) {
-		// XXX: align red zone size with ABI 
-		if (address + 128 < regs->rsp)
+		/* Allow userspace just enough access below the stack pointer
+		 * to let the 'enter' instruction work.
+		 */
+		if (address + 65536 + 32 * sizeof(unsigned long) < regs->rsp)
 			goto bad_area;
 	}
 	if (expand_stack(vma, address))