The patch titled
Subject: uaccess: add missing __must_check attributes
has been added to the -mm tree. Its filename is
uaccess-add-missing-__must_check-attributes.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/uaccess-add-missing-__must_check-attributes.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/uaccess-add-missing-__must_check-attributes.patch
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The -mm tree is included into linux-next and is updated
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------------------------------------------------------
From: Kees Cook <keescook@xxxxxxxxxxxx>
Subject: uaccess: add missing __must_check attributes
The usercopy implementation comments describe that callers of the
copy_*_user() family of functions must always have their return values
checked. This can be enforced at compile time with __must_check, so add
it where needed.
Link: http://lkml.kernel.org/r/201908251609.ADAD5CAAC1@keescook
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/thread_info.h | 2 +-
include/linux/uaccess.h | 21 +++++++++++----------
2 files changed, 12 insertions(+), 11 deletions(-)
--- a/include/linux/thread_info.h~uaccess-add-missing-__must_check-attributes
+++ a/include/linux/thread_info.h
@@ -134,7 +134,7 @@ static inline void copy_overflow(int siz
WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);
}
-static __always_inline bool
+static __always_inline __must_check bool
check_copy_size(const void *addr, size_t bytes, bool is_source)
{
int sz = __compiletime_object_size(addr);
--- a/include/linux/uaccess.h~uaccess-add-missing-__must_check-attributes
+++ a/include/linux/uaccess.h
@@ -55,7 +55,7 @@
* as usual) and both source and destination can trigger faults.
*/
-static __always_inline unsigned long
+static __always_inline __must_check unsigned long
__copy_from_user_inatomic(void *to, const void __user *from, unsigned long n)
{
kasan_check_write(to, n);
@@ -63,7 +63,7 @@ __copy_from_user_inatomic(void *to, cons
return raw_copy_from_user(to, from, n);
}
-static __always_inline unsigned long
+static __always_inline __must_check unsigned long
__copy_from_user(void *to, const void __user *from, unsigned long n)
{
might_fault();
@@ -85,7 +85,7 @@ __copy_from_user(void *to, const void __
* The caller should also make sure he pins the user space address
* so that we don't result in page fault and sleep.
*/
-static __always_inline unsigned long
+static __always_inline __must_check unsigned long
__copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
{
kasan_check_read(from, n);
@@ -93,7 +93,7 @@ __copy_to_user_inatomic(void __user *to,
return raw_copy_to_user(to, from, n);
}
-static __always_inline unsigned long
+static __always_inline __must_check unsigned long
__copy_to_user(void __user *to, const void *from, unsigned long n)
{
might_fault();
@@ -103,7 +103,7 @@ __copy_to_user(void __user *to, const vo
}
#ifdef INLINE_COPY_FROM_USER
-static inline unsigned long
+static inline __must_check unsigned long
_copy_from_user(void *to, const void __user *from, unsigned long n)
{
unsigned long res = n;
@@ -117,12 +117,12 @@ _copy_from_user(void *to, const void __u
return res;
}
#else
-extern unsigned long
+extern __must_check unsigned long
_copy_from_user(void *, const void __user *, unsigned long);
#endif
#ifdef INLINE_COPY_TO_USER
-static inline unsigned long
+static inline __must_check unsigned long
_copy_to_user(void __user *to, const void *from, unsigned long n)
{
might_fault();
@@ -133,7 +133,7 @@ _copy_to_user(void __user *to, const voi
return n;
}
#else
-extern unsigned long
+extern __must_check unsigned long
_copy_to_user(void __user *, const void *, unsigned long);
#endif
@@ -222,8 +222,9 @@ static inline bool pagefault_disabled(vo
#ifndef ARCH_HAS_NOCACHE_UACCESS
-static inline unsigned long __copy_from_user_inatomic_nocache(void *to,
- const void __user *from, unsigned long n)
+static inline __must_check unsigned long
+__copy_from_user_inatomic_nocache(void *to, const void __user *from,
+ unsigned long n)
{
return __copy_from_user_inatomic(to, from, n);
}
_
Patches currently in -mm which might be from keescook@xxxxxxxxxxxx are
strscpy-reject-buffer-sizes-larger-than-int_max.patch
uaccess-add-missing-__must_check-attributes.patch
bug-refactor-away-warn_slowpath_fmt_taint.patch
bug-rename-__warn_printf_taint-to-__warn_printf.patch
bug-consolidate-warn_slowpath_fmt-usage.patch
bug-lift-cut-here-out-of-__warn.patch
bug-clean-up-helper-macros-to-remove-__warn_taint.patch
bug-consolidate-__warn_flags-usage.patch
bug-move-warn_on-cut-here-into-exception-handler.patch
