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 3744b2a8e..1e99c1baf 100644 --- a/lib/usercopy.c +++ b/lib/usercopy.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/uaccess.h> +#include <linux/nospec.h> /* out-of-line parts */ @@ -9,6 +10,12 @@ unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n unsigned long res = n; might_fault(); if (likely(access_ok(VERIFY_READ, 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); } |