From: Andy Lutomirski <luto@MIT.EDU>
Date: Wed, 3 Aug 2011 13:31:49 +0000 (-0400)
Subject: x86-64: Pad vDSO to a page boundary
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=1bdfac19b3ecfca545281c15c7aea7ebc2eaef31;p=deliverable%2Flinux.git

x86-64: Pad vDSO to a page boundary

This avoids an information leak to userspace.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/a63380a3c58a0506a2f5a18ba1b12dbde1f25e58.1312378163.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---

diff --git a/arch/x86/vdso/vdso.S b/arch/x86/vdso/vdso.S
index 1b979c12ba85..01f5e3b4613c 100644
--- a/arch/x86/vdso/vdso.S
+++ b/arch/x86/vdso/vdso.S
@@ -9,6 +9,7 @@ __PAGE_ALIGNED_DATA
 vdso_start:
 	.incbin "arch/x86/vdso/vdso.so"
 vdso_end:
+	.align PAGE_SIZE /* extra data here leaks to userspace. */
 
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