From: Christophe Leroy <christophe.leroy@csgroup.eu>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Paul Mackerras <paulus@samba.org>,
Michael Ellerman <mpe@ellerman.id.au>
Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH v2 13/15] powerpc/uaccess: Refactor get/put_user() and __get/put_user()
Date: Wed, 10 Mar 2021 17:46:52 +0000 (UTC) [thread overview]
Message-ID: <eebc554f6a81f570c46ea3551000ff5b886e4faa.1615398265.git.christophe.leroy@csgroup.eu> (raw)
In-Reply-To: <cover.1615398265.git.christophe.leroy@csgroup.eu>
Make get_user() do the access_ok() check then call __get_user().
Make put_user() do the access_ok() check then call __put_user().
Then embed __get_user_size() and __put_user_size() in
__get_user() and __put_user().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/uaccess.h | 66 +++++++++++-------------------
1 file changed, 23 insertions(+), 43 deletions(-)
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index 616a3a7928c2..671c083f2f2f 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -43,21 +43,6 @@ static inline bool __access_ok(unsigned long addr, unsigned long size)
* exception handling means that it's no longer "just"...)
*
*/
-#define __put_user_size(x, ptr, size, retval) \
-do { \
- __label__ __pu_failed; \
- \
- retval = 0; \
- allow_write_to_user(ptr, size); \
- __put_user_size_goto(x, ptr, size, __pu_failed); \
- prevent_write_to_user(ptr, size); \
- break; \
- \
-__pu_failed: \
- retval = -EFAULT; \
- prevent_write_to_user(ptr, size); \
-} while (0)
-
#define __put_user(x, ptr) \
({ \
long __pu_err; \
@@ -66,23 +51,29 @@ __pu_failed: \
__typeof__(sizeof(*(ptr))) __pu_size = sizeof(*(ptr)); \
\
might_fault(); \
- __put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \
+ do { \
+ __label__ __pu_failed; \
+ \
+ allow_write_to_user(__pu_addr, __pu_size); \
+ __put_user_size_goto(__pu_val, __pu_addr, __pu_size, __pu_failed); \
+ prevent_write_to_user(__pu_addr, __pu_size); \
+ __pu_err = 0; \
+ break; \
+ \
+__pu_failed: \
+ prevent_write_to_user(__pu_addr, __pu_size); \
+ __pu_err = -EFAULT; \
+ } while (0); \
\
__pu_err; \
})
#define put_user(x, ptr) \
({ \
- long __pu_err = -EFAULT; \
- __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
- __typeof__(*(ptr)) __pu_val = (__typeof__(*(ptr)))(x); \
- __typeof__(sizeof(*(ptr))) __pu_size = sizeof(*(ptr)); \
+ __typeof__(*(ptr)) __user *_pu_addr = (ptr); \
\
- might_fault(); \
- if (access_ok(__pu_addr, __pu_size)) \
- __put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \
- \
- __pu_err; \
+ access_ok(_pu_addr, sizeof(*(ptr))) ? \
+ __put_user(x, _pu_addr) : -EFAULT; \
})
/*
@@ -192,13 +183,6 @@ do { \
} \
} while (0)
-#define __get_user_size(x, ptr, size, retval) \
-do { \
- allow_read_from_user(ptr, size); \
- __get_user_size_allowed(x, ptr, size, retval); \
- prevent_read_from_user(ptr, size); \
-} while (0)
-
/*
* This is a type: either unsigned long, if the argument fits into
* that type, or otherwise unsigned long long.
@@ -214,7 +198,9 @@ do { \
__typeof__(sizeof(*(ptr))) __gu_size = sizeof(*(ptr)); \
\
might_fault(); \
- __get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \
+ allow_read_from_user(__gu_addr, __gu_size); \
+ __get_user_size_allowed(__gu_val, __gu_addr, __gu_size, __gu_err); \
+ prevent_read_from_user(__gu_addr, __gu_size); \
(x) = (__typeof__(*(ptr)))__gu_val; \
\
__gu_err; \
@@ -222,17 +208,11 @@ do { \
#define get_user(x, ptr) \
({ \
- long __gu_err = -EFAULT; \
- __long_type(*(ptr)) __gu_val = 0; \
- __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
- __typeof__(sizeof(*(ptr))) __gu_size = sizeof(*(ptr)); \
- \
- might_fault(); \
- if (access_ok(__gu_addr, __gu_size)) \
- __get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \
- (x) = (__force __typeof__(*(ptr)))__gu_val; \
+ __typeof__(*(ptr)) __user *_gu_addr = (ptr); \
\
- __gu_err; \
+ access_ok(_gu_addr, sizeof(*(ptr))) ? \
+ __get_user(x, _gu_addr) : \
+ ((x) = (__force __typeof__(*(ptr)))0, -EFAULT); \
})
/* more complex routines */
--
2.25.0
next prev parent reply other threads:[~2021-03-10 17:48 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-10 17:46 [PATCH v2 00/15] powerpc: Cleanup of uaccess.h and adding asm goto for get_user() Christophe Leroy
2021-03-10 17:46 ` [PATCH v2 01/15] powerpc/uaccess: Remove __get_user_allowed() and unsafe_op_wrap() Christophe Leroy
2021-03-10 21:47 ` Daniel Axtens
2021-03-10 17:46 ` [PATCH v2 02/15] powerpc/uaccess: Define ___get_user_instr() for ppc32 Christophe Leroy
2021-03-10 17:46 ` [PATCH v2 03/15] powerpc/align: Convert emulate_spe() to user_access_begin Christophe Leroy
2021-03-10 22:31 ` Daniel Axtens
2021-03-11 5:45 ` Christophe Leroy
2021-03-12 13:25 ` [PATCH v3 " Christophe Leroy
2021-04-10 14:28 ` Michael Ellerman
2021-03-10 17:46 ` [PATCH v2 04/15] powerpc/uaccess: Remove __get/put_user_inatomic() Christophe Leroy
2021-03-10 22:37 ` Daniel Axtens
2021-03-10 17:46 ` [PATCH v2 05/15] powerpc/uaccess: Move get_user_instr helpers in asm/inst.h Christophe Leroy
2021-03-25 21:59 ` Daniel Axtens
2021-03-10 17:46 ` [PATCH v2 06/15] powerpc/align: Don't use __get_user_instr() on kernel addresses Christophe Leroy
2021-03-25 22:12 ` Daniel Axtens
2021-03-10 17:46 ` [PATCH v2 07/15] powerpc/uaccess: Call might_fault() inconditionaly Christophe Leroy
2021-03-25 22:38 ` Daniel Axtens
2021-03-25 22:44 ` Daniel Axtens
2021-03-10 17:46 ` [PATCH v2 08/15] powerpc/uaccess: Remove __unsafe_put_user_goto() Christophe Leroy
2021-03-10 17:46 ` [PATCH v2 09/15] powerpc/uaccess: Remove __chk_user_ptr() in __get/put_user Christophe Leroy
2021-03-10 17:46 ` [PATCH v2 10/15] powerpc/uaccess: Remove calls to __get_user_bad() and __put_user_bad() Christophe Leroy
2021-03-10 17:46 ` [PATCH v2 11/15] powerpc/uaccess: Split out __get_user_nocheck() Christophe Leroy
2021-03-10 17:46 ` [PATCH v2 12/15] powerpc/uaccess: Rename __get/put_user_check/nocheck Christophe Leroy
2021-03-10 17:46 ` Christophe Leroy [this message]
2021-03-10 17:46 ` [PATCH v2 14/15] powerpc/uaccess: Introduce __get_user_size_goto() Christophe Leroy
2021-03-10 17:46 ` [PATCH v2 15/15] powerpc/uaccess: Use asm goto for get_user when compiler supports it Christophe Leroy
2021-04-10 14:28 ` [PATCH v2 00/15] powerpc: Cleanup of uaccess.h and adding asm goto for get_user() Michael Ellerman
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