2012-06-06 16:05:06

by Arun Sharma

[permalink] [raw]
Subject: [tip:perf/core] perf/x86: Check user address explicitly in copy_from_user_nmi()

Commit-ID: db0dc75d6403b6663c0eab4c6ccb672eb9b2ed72
Gitweb: http://git.kernel.org/tip/db0dc75d6403b6663c0eab4c6ccb672eb9b2ed72
Author: Arun Sharma <[email protected]>
AuthorDate: Fri, 20 Apr 2012 15:41:36 -0700
Committer: Ingo Molnar <[email protected]>
CommitDate: Wed, 6 Jun 2012 17:08:04 +0200

perf/x86: Check user address explicitly in copy_from_user_nmi()

Signed-off-by: Arun Sharma <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: [email protected]
Signed-off-by: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
arch/x86/lib/usercopy.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/arch/x86/lib/usercopy.c b/arch/x86/lib/usercopy.c
index f61ee67..677b1ed 100644
--- a/arch/x86/lib/usercopy.c
+++ b/arch/x86/lib/usercopy.c
@@ -8,6 +8,7 @@
#include <linux/module.h>

#include <asm/word-at-a-time.h>
+#include <linux/sched.h>

/*
* 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)