Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 190 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/book3s/32/kup.h b/arch/powerpc/include/asm/book3s/32/kup.h
new file mode 100644
index 000000000..678f9c9d8
--- /dev/null
+++ b/arch/powerpc/include/asm/book3s/32/kup.h
@@ -0,0 +1,190 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_BOOK3S_32_KUP_H
+#define _ASM_POWERPC_BOOK3S_32_KUP_H
+
+#include <asm/bug.h>
+#include <asm/book3s/32/mmu-hash.h>
+#include <asm/mmu.h>
+#include <asm/synch.h>
+
+#ifndef __ASSEMBLY__
+
+#include <linux/jump_label.h>
+
+extern struct static_key_false disable_kuap_key;
+
+static __always_inline bool kuep_is_disabled(void)
+{
+	return !IS_ENABLED(CONFIG_PPC_KUEP);
+}
+
+#ifdef CONFIG_PPC_KUAP
+
+#include <linux/sched.h>
+
+#define KUAP_NONE	(~0UL)
+#define KUAP_ALL	(~1UL)
+
+static __always_inline bool kuap_is_disabled(void)
+{
+	return static_branch_unlikely(&disable_kuap_key);
+}
+
+static inline void kuap_lock_one(unsigned long addr)
+{
+	mtsr(mfsr(addr) | SR_KS, addr);
+	isync();	/* Context sync required after mtsr() */
+}
+
+static inline void kuap_unlock_one(unsigned long addr)
+{
+	mtsr(mfsr(addr) & ~SR_KS, addr);
+	isync();	/* Context sync required after mtsr() */
+}
+
+static inline void kuap_lock_all(void)
+{
+	update_user_segments(mfsr(0) | SR_KS);
+	isync();	/* Context sync required after mtsr() */
+}
+
+static inline void kuap_unlock_all(void)
+{
+	update_user_segments(mfsr(0) & ~SR_KS);
+	isync();	/* Context sync required after mtsr() */
+}
+
+void kuap_lock_all_ool(void);
+void kuap_unlock_all_ool(void);
+
+static inline void kuap_lock_addr(unsigned long addr, bool ool)
+{
+	if (likely(addr != KUAP_ALL))
+		kuap_lock_one(addr);
+	else if (!ool)
+		kuap_lock_all();
+	else
+		kuap_lock_all_ool();
+}
+
+static inline void kuap_unlock(unsigned long addr, bool ool)
+{
+	if (likely(addr != KUAP_ALL))
+		kuap_unlock_one(addr);
+	else if (!ool)
+		kuap_unlock_all();
+	else
+		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;
+
+	regs->kuap = kuap;
+	if (unlikely(kuap == KUAP_NONE))
+		return;
+
+	current->thread.kuap = KUAP_NONE;
+	kuap_lock_addr(kuap, false);
+}
+
+static inline void kuap_user_restore(struct pt_regs *regs)
+{
+}
+
+static inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long kuap)
+{
+	if (unlikely(kuap != KUAP_NONE)) {
+		current->thread.kuap = KUAP_NONE;
+		kuap_lock_addr(kuap, false);
+	}
+
+	if (likely(regs->kuap == KUAP_NONE))
+		return;
+
+	current->thread.kuap = regs->kuap;
+
+	kuap_unlock(regs->kuap, false);
+}
+
+static inline unsigned long __kuap_get_and_assert_locked(void)
+{
+	unsigned long kuap = current->thread.kuap;
+
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_PPC_KUAP_DEBUG) && kuap != KUAP_NONE);
+
+	return kuap;
+}
+
+static __always_inline void __allow_user_access(void __user *to, const void __user *from,
+						u32 size, unsigned long dir)
+{
+	BUILD_BUG_ON(!__builtin_constant_p(dir));
+
+	if (!(dir & KUAP_WRITE))
+		return;
+
+	current->thread.kuap = (__force u32)to;
+	kuap_unlock_one((__force u32)to);
+}
+
+static __always_inline void __prevent_user_access(unsigned long dir)
+{
+	u32 kuap = current->thread.kuap;
+
+	BUILD_BUG_ON(!__builtin_constant_p(dir));
+
+	if (!(dir & KUAP_WRITE))
+		return;
+
+	current->thread.kuap = KUAP_NONE;
+	kuap_lock_addr(kuap, true);
+}
+
+static inline unsigned long __prevent_user_access_return(void)
+{
+	unsigned long flags = current->thread.kuap;
+
+	if (flags != KUAP_NONE) {
+		current->thread.kuap = KUAP_NONE;
+		kuap_lock_addr(flags, true);
+	}
+
+	return flags;
+}
+
+static inline void __restore_user_access(unsigned long flags)
+{
+	if (flags != KUAP_NONE) {
+		current->thread.kuap = flags;
+		kuap_unlock(flags, true);
+	}
+}
+
+static inline bool
+__bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
+{
+	unsigned long kuap = regs->kuap;
+
+	if (!is_write || kuap == KUAP_ALL)
+		return false;
+	if (kuap == KUAP_NONE)
+		return true;
+
+	/* If faulting address doesn't match unlocked segment, unlock all */
+	if ((kuap ^ address) & 0xf0000000)
+		regs->kuap = KUAP_ALL;
+
+	return false;
+}
+
+#endif /* CONFIG_PPC_KUAP */
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_POWERPC_BOOK3S_32_KUP_H */