x86: some lock annotations for user copy paths

[firefly-linux-kernel-4.4.55.git] / include / asm-x86 / uaccess_32.h

diff --git a/include/asm-x86/uaccess_32.h b/include/asm-x86/uaccess_32.h
index 6fdef39a0bcb849d86e3bb0e1ade448694d21cdb..d725e2d703f7dfa706ed9da3f31053253cb88ffc 100644 (file)
--- a/include/asm-x86/uaccess_32.h
+++ b/include/asm-x86/uaccess_32.h
@@ -82,8 +82,10 @@ __copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
 static __always_inline unsigned long __must_check
 __copy_to_user(void __user *to, const void *from, unsigned long n)
 {
-       might_sleep();
-       return __copy_to_user_inatomic(to, from, n);
+       might_sleep();
+       if (current->mm)
+               might_lock_read(&current->mm->mmap_sem);
+       return __copy_to_user_inatomic(to, from, n);
 }
 
 static __always_inline unsigned long
@@ -138,6 +140,8 @@ static __always_inline unsigned long
 __copy_from_user(void *to, const void __user *from, unsigned long n)
 {
        might_sleep();
+       if (current->mm)
+               might_lock_read(&current->mm->mmap_sem);
        if (__builtin_constant_p(n)) {
                unsigned long ret;
 
@@ -160,6 +164,8 @@ static __always_inline unsigned long __copy_from_user_nocache(void *to,
                                const void __user *from, unsigned long n)
 {
        might_sleep();
+       if (current->mm)
+               might_lock_read(&current->mm->mmap_sem);
        if (__builtin_constant_p(n)) {
                unsigned long ret;