This is a note to let you know that I've just added the patch titled
cris: buggered copy_from_user/copy_to_user/clear_user
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
cris-buggered-copy_from_user-copy_to_user-clear_user.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From eb47e0293baaa3044022059f1fa9ff474bfe35cb Mon Sep 17 00:00:00 2001
From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Date: Thu, 18 Aug 2016 19:34:00 -0400
Subject: cris: buggered copy_from_user/copy_to_user/clear_user
From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
commit eb47e0293baaa3044022059f1fa9ff474bfe35cb upstream.
* copy_from_user() on access_ok() failure ought to zero the destination
* none of those primitives should skip the access_ok() check in case of
small constant size.
Acked-by: Jesper Nilsson <jesper.nilsson@xxxxxxxx>
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/cris/include/asm/uaccess.h | 75 ++++++++++++++++++----------------------
1 file changed, 34 insertions(+), 41 deletions(-)
--- a/arch/cris/include/asm/uaccess.h
+++ b/arch/cris/include/asm/uaccess.h
@@ -194,30 +194,6 @@ extern unsigned long __copy_user(void __
extern unsigned long __copy_user_zeroing(void *to, const void __user *from, unsigned long n);
extern unsigned long __do_clear_user(void __user *to, unsigned long n);
-static inline unsigned long
-__generic_copy_to_user(void __user *to, const void *from, unsigned long n)
-{
- if (access_ok(VERIFY_WRITE, to, n))
- return __copy_user(to, from, n);
- return n;
-}
-
-static inline unsigned long
-__generic_copy_from_user(void *to, const void __user *from, unsigned long n)
-{
- if (access_ok(VERIFY_READ, from, n))
- return __copy_user_zeroing(to, from, n);
- return n;
-}
-
-static inline unsigned long
-__generic_clear_user(void __user *to, unsigned long n)
-{
- if (access_ok(VERIFY_WRITE, to, n))
- return __do_clear_user(to, n);
- return n;
-}
-
static inline long
__strncpy_from_user(char *dst, const char __user *src, long count)
{
@@ -282,7 +258,7 @@ __constant_copy_from_user(void *to, cons
else if (n == 24)
__asm_copy_from_user_24(to, from, ret);
else
- ret = __generic_copy_from_user(to, from, n);
+ ret = __copy_user_zeroing(to, from, n);
return ret;
}
@@ -333,7 +309,7 @@ __constant_copy_to_user(void __user *to,
else if (n == 24)
__asm_copy_to_user_24(to, from, ret);
else
- ret = __generic_copy_to_user(to, from, n);
+ ret = __copy_user(to, from, n);
return ret;
}
@@ -366,26 +342,43 @@ __constant_clear_user(void __user *to, u
else if (n == 24)
__asm_clear_24(to, ret);
else
- ret = __generic_clear_user(to, n);
+ ret = __do_clear_user(to, n);
return ret;
}
-#define clear_user(to, n) \
- (__builtin_constant_p(n) ? \
- __constant_clear_user(to, n) : \
- __generic_clear_user(to, n))
-
-#define copy_from_user(to, from, n) \
- (__builtin_constant_p(n) ? \
- __constant_copy_from_user(to, from, n) : \
- __generic_copy_from_user(to, from, n))
-
-#define copy_to_user(to, from, n) \
- (__builtin_constant_p(n) ? \
- __constant_copy_to_user(to, from, n) : \
- __generic_copy_to_user(to, from, n))
+static inline size_t clear_user(void __user *to, size_t n)
+{
+ if (unlikely(!access_ok(VERIFY_WRITE, to, n)))
+ return n;
+ if (__builtin_constant_p(n))
+ return __constant_clear_user(to, n);
+ else
+ return __do_clear_user(to, n);
+}
+
+static inline size_t copy_from_user(void *to, const void __user *from, size_t n)
+{
+ if (unlikely(!access_ok(VERIFY_READ, from, n))) {
+ memset(to, 0, n);
+ return n;
+ }
+ if (__builtin_constant_p(n))
+ return __constant_copy_from_user(to, from, n);
+ else
+ return __copy_user_zeroing(to, from, n);
+}
+
+static inline size_t copy_to_user(void __user *to, const void *from, size_t n)
+{
+ if (unlikely(!access_ok(VERIFY_WRITE, to, n)))
+ return n;
+ if (__builtin_constant_p(n))
+ return __constant_copy_to_user(to, from, n);
+ else
+ return __copy_user(to, from, n);
+}
/* We let the __ versions of copy_from/to_user inline, because they're often
* used in fast paths and have only a small space overhead.
Patches currently in stable-queue which might be from viro@xxxxxxxxxxxxxxxxxx are
queue-4.4/nios2-copy_from_user-should-zero-the-tail-of-destination.patch
queue-4.4/m32r-fix-__get_user.patch
queue-4.4/microblaze-fix-copy_from_user.patch
queue-4.4/cris-buggered-copy_from_user-copy_to_user-clear_user.patch
queue-4.4/asm-generic-make-copy_from_user-zero-the-destination-properly.patch
queue-4.4/metag-copy_from_user-should-zero-the-destination-on-access_ok-failure.patch
queue-4.4/score-fix-__get_user-get_user.patch
queue-4.4/parisc-fix-copy_from_user.patch
queue-4.4/mips-copy_from_user-must-zero-the-destination-on-access_ok-failure.patch
queue-4.4/alpha-fix-copy_from_user.patch
queue-4.4/mn10300-failing-__get_user-and-get_user-should-zero.patch
queue-4.4/openrisc-fix-copy_from_user.patch
queue-4.4/avr32-fix-copy_from_user.patch
queue-4.4/score-fix-copy_from_user-and-friends.patch
queue-4.4/sh64-failing-__get_user-should-zero.patch
queue-4.4/arc-uaccess-get_user-to-zero-out-dest-in-cause-of-fault.patch
queue-4.4/hexagon-fix-strncpy_from_user-error-return.patch
queue-4.4/frv-fix-clear_user.patch
queue-4.4/fix-minor-infoleak-in-get_user_ex.patch
queue-4.4/asm-generic-make-get_user-clear-the-destination-on-errors.patch
queue-4.4/mn10300-copy_from_user-should-zero-on-access_ok-failure.patch
queue-4.4/s390-get_user-should-zero-on-failure.patch
queue-4.4/microblaze-fix-__get_user.patch
queue-4.4/blackfin-fix-copy_from_user.patch
queue-4.4/fix-iov_iter_fault_in_readable.patch
queue-4.4/nios2-fix-__get_user.patch
queue-4.4/sh-fix-copy_from_user.patch
--
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