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Subject[PATCH v1 7/8] powerpc/futex: Switch to user_access block
Date
Use user_access_begin() instead of the access_ok/allow_access sequence.

This brings the missing might_fault() check.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/include/asm/futex.h | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/include/asm/futex.h b/arch/powerpc/include/asm/futex.h
index e93ee3202e4c..b3001f8b2c1e 100644
--- a/arch/powerpc/include/asm/futex.h
+++ b/arch/powerpc/include/asm/futex.h
@@ -33,9 +33,8 @@ static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
{
int oldval = 0, ret;

- if (!access_ok(uaddr, sizeof(u32)))
+ if (!user_access_begin(uaddr, sizeof(u32)))
return -EFAULT;
- allow_read_write_user(uaddr, uaddr, sizeof(*uaddr));

switch (op) {
case FUTEX_OP_SET:
@@ -56,10 +55,10 @@ static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
default:
ret = -ENOSYS;
}
+ user_access_end();

*oval = oldval;

- prevent_read_write_user(uaddr, uaddr, sizeof(*uaddr));
return ret;
}

@@ -70,11 +69,9 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
int ret = 0;
u32 prev;

- if (!access_ok(uaddr, sizeof(u32)))
+ if (!user_access_begin(uaddr, sizeof(u32)))
return -EFAULT;

- allow_read_write_user(uaddr, uaddr, sizeof(*uaddr));
-
__asm__ __volatile__ (
PPC_ATOMIC_ENTRY_BARRIER
"1: lwarx %1,0,%3 # futex_atomic_cmpxchg_inatomic\n\
@@ -93,8 +90,9 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
: "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT)
: "cc", "memory");

+ user_access_end();
+
*uval = prev;
- prevent_read_write_user(uaddr, uaddr, sizeof(*uaddr));

return ret;
}
--
2.25.0
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