Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "Nothing too bad, but the spectre updates to smatch identified a few
  places that may need sanitising so we've got those covered.

  Details:

   - Close some potential spectre-v1 vulnerabilities found by smatch

   - Add missing list sentinel for CPUs that don't require KPTI

   - Removal of unused 'addr' parameter for I/D cache coherency

   - Removal of redundant set_fs(KERNEL_DS) calls in ptrace

   - Fix single-stepping state machine handling in response to kernel
     traps

   - Clang support for 128-bit integers

   - Avoid instrumenting our out-of-line atomics in preparation for
     enabling LSE atomics by default in 4.18"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: avoid instrumenting atomic_ll_sc.o
  KVM: arm/arm64: vgic: fix possible spectre-v1 in vgic_mmio_read_apr()
  KVM: arm/arm64: vgic: fix possible spectre-v1 in vgic_get_irq()
  arm64: fix possible spectre-v1 in ptrace_hbp_get_event()
  arm64: support __int128 with clang
  arm64: only advance singlestep for user instruction traps
  arm64/kernel: rename module_emit_adrp_veneer->module_emit_veneer_for_adrp
  arm64: ptrace: remove addr_limit manipulation
  arm64: mm: drop addr parameter from sync icache and dcache
  arm64: add sentinel to kpti_safe_list

10 files changed, 27 insertions, 17 deletions

diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 15402861bb59..87f7d2f9f17c 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -56,7 +56,11 @@ KBUILD_AFLAGS	+= $(lseinstr) $(brokengasinst)
 KBUILD_CFLAGS	+= $(call cc-option,-mabi=lp64)
 KBUILD_AFLAGS	+= $(call cc-option,-mabi=lp64)
 
+ifeq ($(cc-name),clang)
+KBUILD_CFLAGS	+= -DCONFIG_ARCH_SUPPORTS_INT128
+else
 KBUILD_CFLAGS	+= $(call cc-ifversion, -ge, 0500, -DCONFIG_ARCH_SUPPORTS_INT128)
+endif
 
 ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
 KBUILD_CPPFLAGS	+= -mbig-endian
diff --git a/arch/arm64/include/asm/module.h b/arch/arm64/include/asm/module.h
index b6dbbe3123a9..97d0ef12e2ff 100644
--- a/arch/arm64/include/asm/module.h
+++ b/arch/arm64/include/asm/module.h
@@ -39,7 +39,7 @@ struct mod_arch_specific {
 u64 module_emit_plt_entry(struct module *mod, void *loc, const Elf64_Rela *rela,
 			  Elf64_Sym *sym);
 
-u64 module_emit_adrp_veneer(struct module *mod, void *loc, u64 val);
+u64 module_emit_veneer_for_adrp(struct module *mod, void *loc, u64 val);
 
 #ifdef CONFIG_RANDOMIZE_BASE
 extern u64 module_alloc_base;
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 7e2c27e63cd8..7c4c8f318ba9 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -230,7 +230,7 @@ static inline void set_pte(pte_t *ptep, pte_t pte)
 	}
 }
 
-extern void __sync_icache_dcache(pte_t pteval, unsigned long addr);
+extern void __sync_icache_dcache(pte_t pteval);
 
 /*
  * PTE bits configuration in the presence of hardware Dirty Bit Management
@@ -253,7 +253,7 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 	pte_t old_pte;
 
 	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
-		__sync_icache_dcache(pte, addr);
+		__sync_icache_dcache(pte);
 
 	/*
 	 * If the existing pte is valid, check for potential race with
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 536d572e5596..9d1b06d67c53 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -868,6 +868,7 @@ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
 	static const struct midr_range kpti_safe_list[] = {
 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
+		{ /* sentinel */ }
 	};
 	char const *str = "command line option";
 
diff --git a/arch/arm64/kernel/module-plts.c b/arch/arm64/kernel/module-plts.c
index fa3637284a3d..f0690c2ca3e0 100644
--- a/arch/arm64/kernel/module-plts.c
+++ b/arch/arm64/kernel/module-plts.c
@@ -43,7 +43,7 @@ u64 module_emit_plt_entry(struct module *mod, void *loc, const Elf64_Rela *rela,
 }
 
 #ifdef CONFIG_ARM64_ERRATUM_843419
-u64 module_emit_adrp_veneer(struct module *mod, void *loc, u64 val)
+u64 module_emit_veneer_for_adrp(struct module *mod, void *loc, u64 val)
 {
 	struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core :
 							  &mod->arch.init;
diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index 719fde8dcc19..155fd91e78f4 100644
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -215,7 +215,7 @@ static int reloc_insn_adrp(struct module *mod, __le32 *place, u64 val)
 		insn &= ~BIT(31);
 	} else {
 		/* out of range for ADR -> emit a veneer */
-		val = module_emit_adrp_veneer(mod, place, val & ~0xfff);
+		val = module_emit_veneer_for_adrp(mod, place, val & ~0xfff);
 		if (!val)
 			return -ENOEXEC;
 		insn = aarch64_insn_gen_branch_imm((u64)place, val,
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 71d99af24ef2..7ff81fed46e1 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -25,6 +25,7 @@
 #include <linux/sched/signal.h>
 #include <linux/sched/task_stack.h>
 #include <linux/mm.h>
+#include <linux/nospec.h>
 #include <linux/smp.h>
 #include <linux/ptrace.h>
 #include <linux/user.h>
@@ -249,15 +250,20 @@ static struct perf_event *ptrace_hbp_get_event(unsigned int note_type,
 
 	switch (note_type) {
 	case NT_ARM_HW_BREAK:
-		if (idx < ARM_MAX_BRP)
-			bp = tsk->thread.debug.hbp_break[idx];
+		if (idx >= ARM_MAX_BRP)
+			goto out;
+		idx = array_index_nospec(idx, ARM_MAX_BRP);
+		bp = tsk->thread.debug.hbp_break[idx];
 		break;
 	case NT_ARM_HW_WATCH:
-		if (idx < ARM_MAX_WRP)
-			bp = tsk->thread.debug.hbp_watch[idx];
+		if (idx >= ARM_MAX_WRP)
+			goto out;
+		idx = array_index_nospec(idx, ARM_MAX_WRP);
+		bp = tsk->thread.debug.hbp_watch[idx];
 		break;
 	}
 
+out:
 	return bp;
 }
 
@@ -1458,9 +1464,7 @@ static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
 {
 	int ret;
 	u32 kdata;
-	mm_segment_t old_fs = get_fs();
 
-	set_fs(KERNEL_DS);
 	/* Watchpoint */
 	if (num < 0) {
 		ret = compat_ptrace_hbp_get(NT_ARM_HW_WATCH, tsk, num, &kdata);
@@ -1471,7 +1475,6 @@ static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
 	} else {
 		ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, &kdata);
 	}
-	set_fs(old_fs);
 
 	if (!ret)
 		ret = put_user(kdata, data);
@@ -1484,7 +1487,6 @@ static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
 {
 	int ret;
 	u32 kdata = 0;
-	mm_segment_t old_fs = get_fs();
 
 	if (num == 0)
 		return 0;
@@ -1493,12 +1495,10 @@ static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
 	if (ret)
 		return ret;
 
-	set_fs(KERNEL_DS);
 	if (num < 0)
 		ret = compat_ptrace_hbp_set(NT_ARM_HW_WATCH, tsk, num, &kdata);
 	else
 		ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, &kdata);
-	set_fs(old_fs);
 
 	return ret;
 }
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 1cb2749a72bf..8bbdc17e49df 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -277,7 +277,8 @@ void arm64_skip_faulting_instruction(struct pt_regs *regs, unsigned long size)
 	 * If we were single stepping, we want to get the step exception after
 	 * we return from the trap.
 	 */
-	user_fastforward_single_step(current);
+	if (user_mode(regs))
+		user_fastforward_single_step(current);
 }
 
 static LIST_HEAD(undef_hook);
diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile
index 0ead8a1d1679..137710f4dac3 100644
--- a/arch/arm64/lib/Makefile
+++ b/arch/arm64/lib/Makefile
@@ -19,5 +19,9 @@ CFLAGS_atomic_ll_sc.o	:= -fcall-used-x0 -ffixed-x1 -ffixed-x2		\
 		   -fcall-saved-x13 -fcall-saved-x14 -fcall-saved-x15	\
 		   -fcall-saved-x18 -fomit-frame-pointer
 CFLAGS_REMOVE_atomic_ll_sc.o := -pg
+GCOV_PROFILE_atomic_ll_sc.o	:= n
+KASAN_SANITIZE_atomic_ll_sc.o	:= n
+KCOV_INSTRUMENT_atomic_ll_sc.o	:= n
+UBSAN_SANITIZE_atomic_ll_sc.o	:= n
 
 lib-$(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) += uaccess_flushcache.o
diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
index e36ed5087b5c..1059884f9a6f 100644
--- a/arch/arm64/mm/flush.c
+++ b/arch/arm64/mm/flush.c
@@ -58,7 +58,7 @@ void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
 	flush_ptrace_access(vma, page, uaddr, dst, len);
 }
 
-void __sync_icache_dcache(pte_t pte, unsigned long addr)
+void __sync_icache_dcache(pte_t pte)
 {
 	struct page *page = pte_page(pte);