lkml.org 
[lkml]   [2021]   [Dec]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
Subject[PATCH 20/43] instrumented.h: add KMSAN support
From
To avoid false positives, KMSAN needs to unpoison the data copied from
the userspace. To detect infoleaks - check the memory buffer passed to
copy_to_user().

Signed-off-by: Alexander Potapenko <glider@google.com>
---
Link: https://linux-review.googlesource.com/id/I43e93b9c02709e6be8d222342f1b044ac8bdbaaf
---
include/linux/instrumented.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/instrumented.h b/include/linux/instrumented.h
index ee8f7d17d34f5..c73c1b19e9227 100644
--- a/include/linux/instrumented.h
+++ b/include/linux/instrumented.h
@@ -2,7 +2,7 @@

/*
* This header provides generic wrappers for memory access instrumentation that
- * the compiler cannot emit for: KASAN, KCSAN.
+ * the compiler cannot emit for: KASAN, KCSAN, KMSAN.
*/
#ifndef _LINUX_INSTRUMENTED_H
#define _LINUX_INSTRUMENTED_H
@@ -10,6 +10,7 @@
#include <linux/compiler.h>
#include <linux/kasan-checks.h>
#include <linux/kcsan-checks.h>
+#include <linux/kmsan-checks.h>
#include <linux/types.h>

/**
@@ -117,6 +118,7 @@ instrument_copy_to_user(void __user *to, const void *from, unsigned long n)
{
kasan_check_read(from, n);
kcsan_check_read(from, n);
+ kmsan_copy_to_user(to, from, n, 0);
}

/**
@@ -151,6 +153,7 @@ static __always_inline void
instrument_copy_from_user_after(const void *to, const void __user *from,
unsigned long n, unsigned long left)
{
+ kmsan_unpoison_memory(to, n - left);
}

#endif /* _LINUX_INSTRUMENTED_H */
--
2.34.1.173.g76aa8bc2d0-goog
\
 
 \ /
  Last update: 2021-12-14 17:24    [W:0.304 / U:2.924 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site