diff options
Diffstat (limited to 'lib/usercopy.c')
| -rw-r--r-- | lib/usercopy.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/lib/usercopy.c b/lib/usercopy.c index cbb4d9ec00f2..82881e0bcaa1 100644 --- a/lib/usercopy.c +++ b/lib/usercopy.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/uaccess.h> #include <linux/bitops.h> +#include <linux/nospec.h> /* out-of-line parts */ @@ -10,6 +11,12 @@ unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n unsigned long res = n; might_fault(); if (likely(access_ok(from, n))) { + /* + * Ensure that bad access_ok() speculation will not + * lead to nasty side effects *after* the copy is + * finished: + */ + barrier_nospec(); kasan_check_write(to, n); res = raw_copy_from_user(to, from, n); } |