diff mbox series

[2/5] powerpc/futex: KHRAP support for futex ops

Message ID 20181017064422.26119-2-ruscur@russell.cc (mailing list archive)
State Superseded
Headers show
Series [1/5] powerpc/64s: Kernel Hypervisor Restricted Access Prevention | expand

Checks

Context Check Description
snowpatch_ozlabs/apply_patch success next/apply_patch Successfully applied
snowpatch_ozlabs/checkpatch success Test checkpatch on branch next

Commit Message

Russell Currey Oct. 17, 2018, 6:44 a.m. UTC 
Wrap the futex operations in KHRAP locks and unlocks.

Signed-off-by: Russell Currey <ruscur@russell.cc>
---
 arch/powerpc/include/asm/futex.h | 6 ++++++
 1 file changed, 6 insertions(+)
diff mbox series

Patch

diff --git a/arch/powerpc/include/asm/futex.h b/arch/powerpc/include/asm/futex.h
index 94542776a62d..e0f4227cfd32 100644
--- a/arch/powerpc/include/asm/futex.h
+++ b/arch/powerpc/include/asm/futex.h
@@ -34,7 +34,9 @@  static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
 		u32 __user *uaddr)
 {
 	int oldval = 0, ret;
+	unsigned long amr;
 
+	amr = unlock_user_access();
 	pagefault_disable();
 
 	switch (op) {
@@ -62,6 +64,7 @@  static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
 	if (!ret)
 		*oval = oldval;
 
+	lock_user_access(amr);
 	return ret;
 }
 
@@ -71,10 +74,12 @@  futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
 {
 	int ret = 0;
 	u32 prev;
+	unsigned long amr;
 
 	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
 		return -EFAULT;
 
+	amr = unlock_user_access();
         __asm__ __volatile__ (
         PPC_ATOMIC_ENTRY_BARRIER
 "1:     lwarx   %1,0,%3         # futex_atomic_cmpxchg_inatomic\n\
@@ -95,6 +100,7 @@  futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
         : "cc", "memory");
 
 	*uval = prev;
+	lock_user_access(amr);
         return ret;
 }