Commit 937fb700 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/kuap: Add kuap_lock() 



Add kuap_lock() and call it when entering interrupts from user.

It is called kuap_lock() as it is similar to kuap_save_and_lock()
without the save.

However book3s/32 already have a kuap_lock(). Rename it
kuap_lock_addr().

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4437e2deb9f6f549f7089d45e9c6f96a7e77905a.1634627931.git.christophe.leroy@csgroup.eu
parent 2341964e

arch/powerpc/include/asm/book3s/32/kup.h

+9 −5
Original line number Diff line number Diff line
@@ -57,7 +57,7 @@ static inline void kuap_unlock_all(void) 
void kuap_lock_all_ool(void);

void kuap_unlock_all_ool(void);



static inline void kuap_lock(unsigned long addr, bool ool)

static inline void kuap_lock_addr(unsigned long addr, bool ool)

{

	if (likely(addr != KUAP_ALL))

		kuap_lock_one(addr);
@@ -77,6 +77,10 @@ static inline void kuap_unlock(unsigned long addr, bool ool) 
		kuap_unlock_all_ool();

}



static inline void __kuap_lock(void)

{

}



static inline void __kuap_save_and_lock(struct pt_regs *regs)

{

	unsigned long kuap = current->thread.kuap;
@@ -86,7 +90,7 @@ static inline void __kuap_save_and_lock(struct pt_regs *regs) 
		return;



	current->thread.kuap = KUAP_NONE;

	kuap_lock(kuap, false);

	kuap_lock_addr(kuap, false);

}



static inline void kuap_user_restore(struct pt_regs *regs)
@@ -97,7 +101,7 @@ static inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long kua 
{

	if (unlikely(kuap != KUAP_NONE)) {

		current->thread.kuap = KUAP_NONE;

		kuap_lock(kuap, false);

		kuap_lock_addr(kuap, false);

	}



	if (likely(regs->kuap == KUAP_NONE))
@@ -139,7 +143,7 @@ static __always_inline void __prevent_user_access(unsigned long dir) 
		return;



	current->thread.kuap = KUAP_NONE;

	kuap_lock(kuap, true);

	kuap_lock_addr(kuap, true);

}



static inline unsigned long __prevent_user_access_return(void)
@@ -148,7 +152,7 @@ static inline unsigned long __prevent_user_access_return(void) 


	if (flags != KUAP_NONE) {

		current->thread.kuap = KUAP_NONE;

		kuap_lock(flags, true);

		kuap_lock_addr(flags, true);

	}



	return flags;

arch/powerpc/include/asm/interrupt.h

+4 −1
Original line number Diff line number Diff line
@@ -140,9 +140,12 @@ static inline void interrupt_enter_prepare(struct pt_regs *regs, struct interrup 
		trace_hardirqs_off();



	if (user_mode(regs))

		account_cpu_user_entry();

		kuap_lock();

	else

		kuap_save_and_lock(regs);



	if (user_mode(regs))

		account_cpu_user_entry();

#endif



#ifdef CONFIG_PPC64

arch/powerpc/include/asm/kup.h

+9 −0
Original line number Diff line number Diff line
@@ -49,6 +49,7 @@ __bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write) 
}



static inline void __kuap_assert_locked(void) { }

static inline void __kuap_lock(void) { }

static inline void __kuap_save_and_lock(struct pt_regs *regs) { }

static inline void kuap_user_restore(struct pt_regs *regs) { }

static inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long amr) { }
@@ -91,6 +92,14 @@ static __always_inline void kuap_assert_locked(void) 
}



#ifdef CONFIG_PPC32

static __always_inline void kuap_lock(void)

{

	if (kuap_is_disabled())

		return;



	__kuap_lock();

}



static __always_inline void kuap_save_and_lock(struct pt_regs *regs)

{

	if (kuap_is_disabled())

arch/powerpc/include/asm/nohash/32/kup-8xx.h

+4 −0
Original line number Diff line number Diff line
@@ -20,6 +20,10 @@ static __always_inline bool kuap_is_disabled(void) 
	return static_branch_unlikely(&disable_kuap_key);

}



static inline void __kuap_lock(void)

{

}



static inline void __kuap_save_and_lock(struct pt_regs *regs)

{

	regs->kuap = mfspr(SPRN_MD_AP);

arch/powerpc/kernel/interrupt.c

+2 −0
Original line number Diff line number Diff line
@@ -81,6 +81,8 @@ notrace long system_call_exception(long r3, long r4, long r5, 
{

	syscall_fn f;



	kuap_lock();



	regs->orig_gpr3 = r3;



	if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG))