From db0dc75d6403b6663c0eab4c6ccb672eb9b2ed72 Mon Sep 17 00:00:00 2001 From: Arun Sharma Date: Fri, 20 Apr 2012 15:41:36 -0700 Subject: [PATCH] perf/x86: Check user address explicitly in copy_from_user_nmi() Signed-off-by: Arun Sharma Cc: Linus Torvalds Cc: linux-kernel@vger.kernel.org Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1334961696-19580-5-git-send-email-asharma@fb.com Signed-off-by: Ingo Molnar --- arch/x86/lib/usercopy.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/lib/usercopy.c b/arch/x86/lib/usercopy.c index f61ee67ec00f..677b1ed184c9 100644 --- a/arch/x86/lib/usercopy.c +++ b/arch/x86/lib/usercopy.c @@ -8,6 +8,7 @@ #include #include +#include /* * best effort, GUP based copy_from_user() that is NMI-safe @@ -21,6 +22,9 @@ copy_from_user_nmi(void *to, const void __user *from, unsigned long n) void *map; int ret; + if (__range_not_ok(from, n, TASK_SIZE) == 0) + return len; + do { ret = __get_user_pages_fast(addr, 1, 0, &page); if (!ret)