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From: Sami Tolvanen <samitolvanen@google.com>
To: Will Deacon <will@kernel.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	 Steven Rostedt <rostedt@goodmis.org>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	 Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Dave Martin <Dave.Martin@arm.com>,
	Kees Cook <keescook@chromium.org>,
	 Laura Abbott <labbott@redhat.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Marc Zyngier <maz@kernel.org>,
	 Nick Desaulniers <ndesaulniers@google.com>,
	Jann Horn <jannh@google.com>,
	 Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
	 Masahiro Yamada <yamada.masahiro@socionext.com>,
	clang-built-linux@googlegroups.com,
	 kernel-hardening@lists.openwall.com,
	linux-arm-kernel@lists.infradead.org,
	 linux-kernel@vger.kernel.org,
	Sami Tolvanen <samitolvanen@google.com>
Subject: [PATCH v5 05/14] add support for Clang's Shadow Call Stack (SCS)
Date: Tue,  5 Nov 2019 15:55:59 -0800
Message-ID: <20191105235608.107702-6-samitolvanen@google.com> (raw)
In-Reply-To: <20191105235608.107702-1-samitolvanen@google.com>

This change adds generic support for Clang's Shadow Call Stack,
which uses a shadow stack to protect return addresses from being
overwritten by an attacker. Details are available here:

  https://clang.llvm.org/docs/ShadowCallStack.html

Note that security guarantees in the kernel differ from the
ones documented for user space. The kernel must store addresses
of shadow stacks used by other tasks and interrupt handlers in
memory, which means an attacker capable reading and writing
arbitrary memory may be able to locate them and hijack control
flow by modifying shadow stacks that are not currently in use.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
---
 Makefile                       |   6 ++
 arch/Kconfig                   |  33 ++++++
 include/linux/compiler-clang.h |   6 ++
 include/linux/compiler_types.h |   4 +
 include/linux/scs.h            |  57 ++++++++++
 init/init_task.c               |   8 ++
 kernel/Makefile                |   1 +
 kernel/fork.c                  |   9 ++
 kernel/sched/core.c            |   2 +
 kernel/scs.c                   | 187 +++++++++++++++++++++++++++++++++
 10 files changed, 313 insertions(+)
 create mode 100644 include/linux/scs.h
 create mode 100644 kernel/scs.c

diff --git a/Makefile b/Makefile
index b37d0e8fc61d..7f3a4c5c7dcc 100644
--- a/Makefile
+++ b/Makefile
@@ -846,6 +846,12 @@ ifdef CONFIG_LIVEPATCH
 KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
 endif
 
+ifdef CONFIG_SHADOW_CALL_STACK
+CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
+KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
+export CC_FLAGS_SCS
+endif
+
 # arch Makefile may override CC so keep this after arch Makefile is included
 NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
 
diff --git a/arch/Kconfig b/arch/Kconfig
index 5f8a5d84dbbe..5e34cbcd8d6a 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -521,6 +521,39 @@ config STACKPROTECTOR_STRONG
 	  about 20% of all kernel functions, which increases the kernel code
 	  size by about 2%.
 
+config ARCH_SUPPORTS_SHADOW_CALL_STACK
+	bool
+	help
+	  An architecture should select this if it supports Clang's Shadow
+	  Call Stack, has asm/scs.h, and implements runtime support for shadow
+	  stack switching.
+
+config SHADOW_CALL_STACK_VMAP
+	bool
+	depends on SHADOW_CALL_STACK
+	help
+	  Use virtually mapped shadow call stacks. Selecting this option
+	  provides better stack exhaustion protection, but increases per-thread
+	  memory consumption as a full page is allocated for each shadow stack.
+
+config SHADOW_CALL_STACK
+	bool "Clang Shadow Call Stack"
+	depends on ARCH_SUPPORTS_SHADOW_CALL_STACK
+	help
+	  This option enables Clang's Shadow Call Stack, which uses a
+	  shadow stack to protect function return addresses from being
+	  overwritten by an attacker. More information can be found from
+	  Clang's documentation:
+
+	    https://clang.llvm.org/docs/ShadowCallStack.html
+
+	  Note that security guarantees in the kernel differ from the ones
+	  documented for user space. The kernel must store addresses of shadow
+	  stacks used by other tasks and interrupt handlers in memory, which
+	  means an attacker capable reading and writing arbitrary memory may
+	  be able to locate them and hijack control flow by modifying shadow
+	  stacks that are not currently in use.
+
 config HAVE_ARCH_WITHIN_STACK_FRAMES
 	bool
 	help
diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h
index 333a6695a918..18fc4d29ef27 100644
--- a/include/linux/compiler-clang.h
+++ b/include/linux/compiler-clang.h
@@ -42,3 +42,9 @@
  * compilers, like ICC.
  */
 #define barrier() __asm__ __volatile__("" : : : "memory")
+
+#if __has_feature(shadow_call_stack)
+# define __noscs	__attribute__((__no_sanitize__("shadow-call-stack")))
+#else
+# define __noscs
+#endif
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
index 72393a8c1a6c..be5d5be4b1ae 100644
--- a/include/linux/compiler_types.h
+++ b/include/linux/compiler_types.h
@@ -202,6 +202,10 @@ struct ftrace_likely_data {
 # define randomized_struct_fields_end
 #endif
 
+#ifndef __noscs
+# define __noscs
+#endif
+
 #ifndef asm_volatile_goto
 #define asm_volatile_goto(x...) asm goto(x)
 #endif
diff --git a/include/linux/scs.h b/include/linux/scs.h
new file mode 100644
index 000000000000..c5572fd770b0
--- /dev/null
+++ b/include/linux/scs.h
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Shadow Call Stack support.
+ *
+ * Copyright (C) 2019 Google LLC
+ */
+
+#ifndef _LINUX_SCS_H
+#define _LINUX_SCS_H
+
+#include <linux/gfp.h>
+#include <linux/sched.h>
+#include <asm/page.h>
+
+#ifdef CONFIG_SHADOW_CALL_STACK
+
+/*
+ * In testing, 1 KiB shadow stack size (i.e. 128 stack frames on a 64-bit
+ * architecture) provided ~40% safety margin on stack usage while keeping
+ * memory allocation overhead reasonable.
+ */
+#define SCS_SIZE	1024UL
+#define GFP_SCS		(GFP_KERNEL | __GFP_ZERO)
+
+/*
+ * A random number outside the kernel's virtual address space to mark the
+ * end of the shadow stack.
+ */
+#define SCS_END_MAGIC	0xaf0194819b1635f6UL
+
+#define task_scs(tsk)	(task_thread_info(tsk)->shadow_call_stack)
+
+static inline void task_set_scs(struct task_struct *tsk, void *s)
+{
+	task_scs(tsk) = s;
+}
+
+extern void scs_init(void);
+extern void scs_task_reset(struct task_struct *tsk);
+extern int scs_prepare(struct task_struct *tsk, int node);
+extern bool scs_corrupted(struct task_struct *tsk);
+extern void scs_release(struct task_struct *tsk);
+
+#else /* CONFIG_SHADOW_CALL_STACK */
+
+#define task_scs(tsk)	NULL
+
+static inline void task_set_scs(struct task_struct *tsk, void *s) {}
+static inline void scs_init(void) {}
+static inline void scs_task_reset(struct task_struct *tsk) {}
+static inline int scs_prepare(struct task_struct *tsk, int node) { return 0; }
+static inline bool scs_corrupted(struct task_struct *tsk) { return false; }
+static inline void scs_release(struct task_struct *tsk) {}
+
+#endif /* CONFIG_SHADOW_CALL_STACK */
+
+#endif /* _LINUX_SCS_H */
diff --git a/init/init_task.c b/init/init_task.c
index 9e5cbe5eab7b..cbd40460e903 100644
--- a/init/init_task.c
+++ b/init/init_task.c
@@ -11,6 +11,7 @@
 #include <linux/mm.h>
 #include <linux/audit.h>
 #include <linux/numa.h>
+#include <linux/scs.h>
 
 #include <asm/pgtable.h>
 #include <linux/uaccess.h>
@@ -184,6 +185,13 @@ struct task_struct init_task
 };
 EXPORT_SYMBOL(init_task);
 
+#ifdef CONFIG_SHADOW_CALL_STACK
+unsigned long init_shadow_call_stack[SCS_SIZE / sizeof(long)] __init_task_data
+		__aligned(SCS_SIZE) = {
+	[(SCS_SIZE / sizeof(long)) - 1] = SCS_END_MAGIC
+};
+#endif
+
 /*
  * Initial thread structure. Alignment of this is handled by a special
  * linker map entry.
diff --git a/kernel/Makefile b/kernel/Makefile
index daad787fb795..313dbd44d576 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -102,6 +102,7 @@ obj-$(CONFIG_TRACEPOINTS) += trace/
 obj-$(CONFIG_IRQ_WORK) += irq_work.o
 obj-$(CONFIG_CPU_PM) += cpu_pm.o
 obj-$(CONFIG_BPF) += bpf/
+obj-$(CONFIG_SHADOW_CALL_STACK) += scs.o
 
 obj-$(CONFIG_PERF_EVENTS) += events/
 
diff --git a/kernel/fork.c b/kernel/fork.c
index 55af6931c6ec..6c4266019935 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -94,6 +94,7 @@
 #include <linux/livepatch.h>
 #include <linux/thread_info.h>
 #include <linux/stackleak.h>
+#include <linux/scs.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -451,6 +452,8 @@ void put_task_stack(struct task_struct *tsk)
 
 void free_task(struct task_struct *tsk)
 {
+	scs_release(tsk);
+
 #ifndef CONFIG_THREAD_INFO_IN_TASK
 	/*
 	 * The task is finally done with both the stack and thread_info,
@@ -834,6 +837,8 @@ void __init fork_init(void)
 			  NULL, free_vm_stack_cache);
 #endif
 
+	scs_init();
+
 	lockdep_init_task(&init_task);
 	uprobes_init();
 }
@@ -893,6 +898,10 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node)
 	if (err)
 		goto free_stack;
 
+	err = scs_prepare(tsk, node);
+	if (err)
+		goto free_stack;
+
 #ifdef CONFIG_SECCOMP
 	/*
 	 * We must handle setting up seccomp filters once we're under
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index dd05a378631a..6769e27052bf 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -11,6 +11,7 @@
 #include <linux/nospec.h>
 
 #include <linux/kcov.h>
+#include <linux/scs.h>
 
 #include <asm/switch_to.h>
 #include <asm/tlb.h>
@@ -6018,6 +6019,7 @@ void init_idle(struct task_struct *idle, int cpu)
 	idle->se.exec_start = sched_clock();
 	idle->flags |= PF_IDLE;
 
+	scs_task_reset(idle);
 	kasan_unpoison_task_stack(idle);
 
 #ifdef CONFIG_SMP
diff --git a/kernel/scs.c b/kernel/scs.c
new file mode 100644
index 000000000000..e3234a4b92ec
--- /dev/null
+++ b/kernel/scs.c
@@ -0,0 +1,187 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Shadow Call Stack support.
+ *
+ * Copyright (C) 2019 Google LLC
+ */
+
+#include <linux/cpuhotplug.h>
+#include <linux/kasan.h>
+#include <linux/mm.h>
+#include <linux/mmzone.h>
+#include <linux/scs.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <asm/scs.h>
+
+static inline void *__scs_base(struct task_struct *tsk)
+{
+	/*
+	 * To minimize risk the of exposure, architectures may clear a
+	 * task's thread_info::shadow_call_stack while that task is
+	 * running, and only save/restore the active shadow call stack
+	 * pointer when the usual register may be clobbered (e.g. across
+	 * context switches).
+	 *
+	 * The shadow call stack is aligned to SCS_SIZE, and grows
+	 * upwards, so we can mask out the low bits to extract the base
+	 * when the task is not running.
+	 */
+	return (void *)((unsigned long)task_scs(tsk) & ~(SCS_SIZE - 1));
+}
+
+static inline unsigned long *scs_magic(void *s)
+{
+	return (unsigned long *)(s + SCS_SIZE) - 1;
+}
+
+static inline void scs_set_magic(void *s)
+{
+	*scs_magic(s) = SCS_END_MAGIC;
+}
+
+#ifdef CONFIG_SHADOW_CALL_STACK_VMAP
+
+/* Matches NR_CACHED_STACKS for VMAP_STACK */
+#define NR_CACHED_SCS 2
+static DEFINE_PER_CPU(void *, scs_cache[NR_CACHED_SCS]);
+
+static void *scs_alloc(int node)
+{
+	int i;
+	void *s;
+
+	for (i = 0; i < NR_CACHED_SCS; i++) {
+		s = this_cpu_xchg(scs_cache[i], NULL);
+		if (s) {
+			memset(s, 0, SCS_SIZE);
+			goto out;
+		}
+	}
+
+	/*
+	 * We allocate a full page for the shadow stack, which should be
+	 * more than we need. Check the assumption nevertheless.
+	 */
+	BUILD_BUG_ON(SCS_SIZE > PAGE_SIZE);
+
+	s = __vmalloc_node_range(PAGE_SIZE, SCS_SIZE,
+				 VMALLOC_START, VMALLOC_END,
+				 GFP_SCS, PAGE_KERNEL, 0,
+				 node, __builtin_return_address(0));
+
+out:
+	if (s)
+		scs_set_magic(s);
+	/* TODO: poison for KASAN, unpoison in scs_free */
+
+	return s;
+}
+
+static void scs_free(void *s)
+{
+	int i;
+
+	for (i = 0; i < NR_CACHED_SCS; i++)
+		if (this_cpu_cmpxchg(scs_cache[i], 0, s) == NULL)
+			return;
+
+	vfree_atomic(s);
+}
+
+static int scs_cleanup(unsigned int cpu)
+{
+	int i;
+	void **cache = per_cpu_ptr(scs_cache, cpu);
+
+	for (i = 0; i < NR_CACHED_SCS; i++) {
+		vfree(cache[i]);
+		cache[i] = NULL;
+	}
+
+	return 0;
+}
+
+void __init scs_init(void)
+{
+	WARN_ON(cpuhp_setup_state(CPUHP_BP_PREPARE_DYN, "scs:scs_cache", NULL,
+			scs_cleanup));
+}
+
+#else /* !CONFIG_SHADOW_CALL_STACK_VMAP */
+
+static struct kmem_cache *scs_cache;
+
+static inline void *scs_alloc(int node)
+{
+	void *s;
+
+	s = kmem_cache_alloc_node(scs_cache, GFP_SCS, node);
+	if (s) {
+		scs_set_magic(s);
+		/*
+		 * Poison the allocation to catch unintentional accesses to
+		 * the shadow stack when KASAN is enabled.
+		 */
+		kasan_poison_object_data(scs_cache, s);
+	}
+
+	return s;
+}
+
+static inline void scs_free(void *s)
+{
+	kasan_unpoison_object_data(scs_cache, s);
+	kmem_cache_free(scs_cache, s);
+}
+
+void __init scs_init(void)
+{
+	scs_cache = kmem_cache_create("scs_cache", SCS_SIZE, SCS_SIZE,
+				0, NULL);
+	WARN_ON(!scs_cache);
+}
+
+#endif /* CONFIG_SHADOW_CALL_STACK_VMAP */
+
+void scs_task_reset(struct task_struct *tsk)
+{
+	/*
+	 * Reset the shadow stack to the base address in case the task
+	 * is reused.
+	 */
+	task_set_scs(tsk, __scs_base(tsk));
+}
+
+int scs_prepare(struct task_struct *tsk, int node)
+{
+	void *s;
+
+	s = scs_alloc(node);
+	if (!s)
+		return -ENOMEM;
+
+	task_set_scs(tsk, s);
+	return 0;
+}
+
+bool scs_corrupted(struct task_struct *tsk)
+{
+	unsigned long *magic = scs_magic(__scs_base(tsk));
+
+	return READ_ONCE_NOCHECK(*magic) != SCS_END_MAGIC;
+}
+
+void scs_release(struct task_struct *tsk)
+{
+	void *s;
+
+	s = __scs_base(tsk);
+	if (!s)
+		return;
+
+	WARN_ON(scs_corrupted(tsk));
+
+	task_set_scs(tsk, NULL);
+	scs_free(s);
+}
-- 
2.24.0.rc1.363.gb1bccd3e3d-goog


  parent reply index

Thread overview: 236+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-18 16:10 [PATCH 00/18] add support for Clang's Shadow Call Stack Sami Tolvanen
2019-10-18 16:10 ` [PATCH 01/18] arm64: mm: don't use x18 in idmap_kpti_install_ng_mappings Sami Tolvanen
2019-10-18 16:43   ` Nick Desaulniers
2019-10-18 16:10 ` [PATCH 02/18] arm64/lib: copy_page: avoid x18 register in assembler code Sami Tolvanen
2019-10-18 16:10 ` [PATCH 03/18] arm64: kvm: stop treating register x18 as caller save Sami Tolvanen
2019-10-21  6:19   ` Ard Biesheuvel
2019-10-22 17:22   ` Marc Zyngier
2019-10-22 21:45     ` Sami Tolvanen
2019-10-18 16:10 ` [PATCH 04/18] arm64: kernel: avoid x18 as an arbitrary temp register Sami Tolvanen
2019-10-18 16:10 ` [PATCH 05/18] arm64: kbuild: reserve reg x18 from general allocation by the compiler Sami Tolvanen
2019-10-18 17:32   ` Nick Desaulniers
2019-10-18 19:00     ` Sami Tolvanen
2019-10-21  6:12       ` Ard Biesheuvel
2019-10-21 20:43         ` Sami Tolvanen
2019-10-18 16:10 ` [PATCH 06/18] add support for Clang's Shadow Call Stack (SCS) Sami Tolvanen
2019-10-18 16:58   ` Joe Perches
2019-10-18 17:08   ` Nick Desaulniers
2019-10-18 17:11     ` Sami Tolvanen
2019-10-18 18:32       ` Miguel Ojeda
2019-10-18 20:33         ` Nick Desaulniers
2019-10-19  0:21           ` Miguel Ojeda
2019-10-18 17:42   ` Jann Horn
2019-10-18 17:56     ` Sami Tolvanen
2019-10-22 16:28   ` Mark Rutland
2019-10-22 16:30     ` Kees Cook
2019-10-22 16:49       ` Mark Rutland
2019-10-22 19:26     ` Sami Tolvanen
2019-10-24 13:28       ` Mark Rutland
2019-10-24 14:38         ` Masahiro Yamada
2019-10-23 16:59     ` Sami Tolvanen
2019-10-24  1:47       ` Masahiro Yamada
2019-10-24 12:04       ` Steven Rostedt
2019-10-24 22:17         ` Sami Tolvanen
2019-10-18 16:10 ` [PATCH 07/18] scs: add accounting Sami Tolvanen
2019-10-18 16:10 ` [PATCH 08/18] scs: add support for stack usage debugging Sami Tolvanen
2019-10-18 16:10 ` [PATCH 09/18] trace: disable function graph tracing with SCS Sami Tolvanen
2019-10-18 17:01   ` Steven Rostedt
2019-10-18 17:08     ` Sami Tolvanen
2019-10-21  6:15   ` Ard Biesheuvel
2019-10-18 16:10 ` [PATCH 10/18] kprobes: fix compilation without CONFIG_KRETPROBES Sami Tolvanen
2019-10-18 17:02   ` Steven Rostedt
2019-10-21  9:13     ` Masami Hiramatsu
2019-10-18 16:10 ` [PATCH 11/18] kprobes: disable kretprobes with SCS Sami Tolvanen
2019-10-18 17:04   ` Steven Rostedt
2019-10-21  9:15     ` Masami Hiramatsu
2019-10-18 16:10 ` [PATCH 12/18] arm64: reserve x18 only with Shadow Call Stack Sami Tolvanen
2019-10-18 21:23   ` Nick Desaulniers
2019-10-22 16:00     ` Mark Rutland
2019-10-22 16:27       ` Kees Cook
2019-10-18 16:10 ` [PATCH 13/18] arm64: preserve x18 when CPU is suspended Sami Tolvanen
2019-10-18 16:49   ` Nick Desaulniers
2019-10-18 17:05     ` Sami Tolvanen
2019-10-21 16:56   ` Mark Rutland
2019-10-21 22:43     ` Sami Tolvanen
2019-10-22 15:47       ` Mark Rutland
2019-10-18 16:10 ` [PATCH 14/18] arm64: efi: restore x18 if it was corrupted Sami Tolvanen
2019-10-21  6:20   ` Ard Biesheuvel
2019-10-21 22:39     ` Sami Tolvanen
2019-10-22  5:54       ` Ard Biesheuvel
2019-10-18 16:10 ` [PATCH 15/18] arm64: vdso: disable Shadow Call Stack Sami Tolvanen
2019-10-18 16:10 ` [PATCH 16/18] arm64: kprobes: fix kprobes without CONFIG_KRETPROBES Sami Tolvanen
2019-10-21  6:21   ` Ard Biesheuvel
2019-10-21 16:06     ` Kees Cook
2019-10-18 16:10 ` [PATCH 17/18] arm64: disable SCS for hypervisor code Sami Tolvanen
2019-10-18 16:10 ` [PATCH 18/18] arm64: implement Shadow Call Stack Sami Tolvanen
2019-10-18 17:12   ` Jann Horn
2019-10-18 17:18     ` Sami Tolvanen
2019-10-18 17:23     ` Mark Rutland
2019-10-18 17:35       ` Sami Tolvanen
2019-10-21 16:49         ` Mark Rutland
2019-10-21  9:28 ` [PATCH 00/18] add support for Clang's " Masami Hiramatsu
2019-10-24 22:51 ` [PATCH v2 00/17] " samitolvanen
2019-10-24 22:51   ` [PATCH v2 01/17] arm64: mm: don't use x18 in idmap_kpti_install_ng_mappings samitolvanen
2019-10-25  9:24     ` Mark Rutland
2019-10-24 22:51   ` [PATCH v2 02/17] arm64/lib: copy_page: avoid x18 register in assembler code samitolvanen
2019-10-25  9:41     ` Mark Rutland
2019-10-25 21:40       ` Sami Tolvanen
2019-10-24 22:51   ` [PATCH v2 03/17] arm64: kvm: stop treating register x18 as caller save samitolvanen
2019-10-24 22:51   ` [PATCH v2 04/17] arm64: kernel: avoid x18 as an arbitrary temp register samitolvanen
2019-10-25 10:02     ` Mark Rutland
2019-10-24 22:51   ` [PATCH v2 05/17] add support for Clang's Shadow Call Stack (SCS) samitolvanen
2019-10-25 10:56     ` Mark Rutland
2019-10-25 20:49       ` Sami Tolvanen
2019-10-28 16:35         ` Mark Rutland
2019-10-28 19:57           ` Kees Cook
2019-10-29 18:06             ` Sami Tolvanen
2019-10-25 16:22     ` Nick Desaulniers
2019-10-25 20:51       ` Sami Tolvanen
2019-10-26 15:57     ` Joe Perches
2019-10-28 15:19       ` Sami Tolvanen
2019-10-28 15:31         ` Miguel Ojeda
2019-10-28 16:15           ` Sami Tolvanen
2019-10-24 22:51   ` [PATCH v2 06/17] scs: add accounting samitolvanen
2019-10-24 22:51   ` [PATCH v2 07/17] scs: add support for stack usage debugging samitolvanen
2019-10-24 22:51   ` [PATCH v2 08/17] kprobes: fix compilation without CONFIG_KRETPROBES samitolvanen
2019-10-24 22:51   ` [PATCH v2 09/17] arm64: disable function graph tracing with SCS samitolvanen
2019-10-25 11:03     ` Mark Rutland
2019-10-29 17:45       ` Sami Tolvanen
2019-10-29 20:35         ` Nick Desaulniers
2019-10-24 22:51   ` [PATCH v2 10/17] arm64: disable kretprobes " samitolvanen
2019-10-24 22:51   ` [PATCH v2 11/17] arm64: reserve x18 from general allocation " samitolvanen
2019-10-24 22:51   ` [PATCH v2 12/17] arm64: preserve x18 when CPU is suspended samitolvanen
2019-10-24 22:51   ` [PATCH v2 13/17] arm64: efi: restore x18 if it was corrupted samitolvanen
2019-10-24 22:51   ` [PATCH v2 14/17] arm64: vdso: disable Shadow Call Stack samitolvanen
2019-10-24 22:51   ` [PATCH v2 15/17] arm64: kprobes: fix kprobes without CONFIG_KRETPROBES samitolvanen
2019-10-24 22:51   ` [PATCH v2 16/17] arm64: disable SCS for hypervisor code samitolvanen
2019-10-25  1:20     ` Steven Rostedt
2019-10-25  1:29     ` Masahiro Yamada
2019-10-25  1:42       ` Steven Rostedt
2019-10-25 19:24       ` Sami Tolvanen
2019-10-24 22:51   ` [PATCH v2 17/17] arm64: implement Shadow Call Stack samitolvanen
2019-10-31 16:46 ` [PATCH v3 00/17] add support for Clang's " samitolvanen
2019-10-31 16:46   ` [PATCH v3 01/17] arm64: mm: avoid x18 in idmap_kpti_install_ng_mappings samitolvanen
2019-10-31 16:46   ` [PATCH v3 02/17] arm64/lib: copy_page: avoid x18 register in assembler code samitolvanen
2019-10-31 16:46   ` [PATCH v3 03/17] arm64: kvm: stop treating register x18 as caller save samitolvanen
2019-11-01  3:48     ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 04/17] arm64: kernel: avoid x18 __cpu_soft_restart samitolvanen
2019-11-01  3:47     ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 05/17] add support for Clang's Shadow Call Stack (SCS) samitolvanen
2019-11-01  3:51     ` Kees Cook
2019-11-01 16:28       ` Sami Tolvanen
2019-10-31 16:46   ` [PATCH v3 06/17] scs: add accounting samitolvanen
2019-11-01  3:52     ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 07/17] scs: add support for stack usage debugging samitolvanen
2019-11-01  3:55     ` Kees Cook
2019-11-01 16:32       ` Sami Tolvanen
2019-11-01 19:02         ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 08/17] kprobes: fix compilation without CONFIG_KRETPROBES samitolvanen
2019-11-01  3:55     ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 09/17] arm64: kprobes: fix kprobes " samitolvanen
2019-11-01  3:56     ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 10/17] arm64: disable kretprobes with SCS samitolvanen
2019-11-01  3:56     ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 11/17] arm64: disable function graph tracing " samitolvanen
2019-11-01  3:58     ` Kees Cook
2019-11-01 20:32       ` Sami Tolvanen
2019-10-31 16:46   ` [PATCH v3 12/17] arm64: reserve x18 from general allocation " samitolvanen
2019-10-31 17:11     ` Nick Desaulniers
2019-11-01  3:59     ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 13/17] arm64: preserve x18 when CPU is suspended samitolvanen
2019-10-31 17:18     ` Nick Desaulniers
2019-10-31 17:27       ` Sami Tolvanen
2019-10-31 17:34         ` Nick Desaulniers
2019-10-31 17:42           ` Sami Tolvanen
2019-11-01  3:59           ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 14/17] arm64: efi: restore x18 if it was corrupted samitolvanen
2019-11-01  4:00     ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 15/17] arm64: vdso: disable Shadow Call Stack samitolvanen
2019-10-31 17:28     ` Nick Desaulniers
2019-11-01  4:01     ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 16/17] arm64: disable SCS for hypervisor code samitolvanen
2019-11-01  3:46     ` Kees Cook
2019-11-01  4:02     ` Kees Cook
2019-10-31 16:46   ` [PATCH v3 17/17] arm64: implement Shadow Call Stack samitolvanen
2019-11-01  3:45     ` Kees Cook
2019-11-01 15:44       ` Sami Tolvanen
2019-11-01 22:11 ` [PATCH v4 00/17] add support for Clang's " Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 01/17] arm64: mm: avoid x18 in idmap_kpti_install_ng_mappings Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 02/17] arm64/lib: copy_page: avoid x18 register in assembler code Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 03/17] arm64: kvm: stop treating register x18 as caller save Sami Tolvanen
2019-11-04 11:04     ` Marc Zyngier
2019-11-04 13:30       ` Marc Zyngier
2019-11-04 11:51     ` Mark Rutland
2019-11-04 21:44       ` Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 04/17] arm64: kernel: avoid x18 __cpu_soft_restart Sami Tolvanen
2019-11-04 11:39     ` Mark Rutland
2019-11-04 16:44       ` Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 05/17] add support for Clang's Shadow Call Stack (SCS) Sami Tolvanen
2019-11-01 22:36     ` Miguel Ojeda
2019-11-04 12:31     ` Mark Rutland
2019-11-04 18:25       ` Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 06/17] scs: add accounting Sami Tolvanen
2019-11-04 13:13     ` Marc Zyngier
2019-11-04 16:42       ` Sami Tolvanen
2019-11-04 16:59         ` Marc Zyngier
2019-11-01 22:11   ` [PATCH v4 07/17] scs: add support for stack usage debugging Sami Tolvanen
2019-11-02 17:31     ` Kees Cook
2019-11-04 12:40     ` Mark Rutland
2019-11-04 21:35       ` Sami Tolvanen
2019-11-05  9:17         ` Mark Rutland
2019-11-01 22:11   ` [PATCH v4 08/17] kprobes: fix compilation without CONFIG_KRETPROBES Sami Tolvanen
2019-11-13 20:27     ` Steven Rostedt
2019-11-01 22:11   ` [PATCH v4 09/17] arm64: kprobes: fix kprobes " Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 10/17] arm64: disable kretprobes with SCS Sami Tolvanen
2019-11-04 17:04     ` Mark Rutland
2019-11-04 23:42       ` Sami Tolvanen
2019-11-05  9:04         ` Mark Rutland
2019-11-01 22:11   ` [PATCH v4 11/17] arm64: disable function graph tracing " Sami Tolvanen
2019-11-04 17:11     ` Mark Rutland
2019-11-04 23:44       ` Sami Tolvanen
2019-11-05  9:15         ` Mark Rutland
2019-11-05 20:00           ` Nick Desaulniers
2019-11-05 22:05           ` Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 12/17] arm64: reserve x18 from general allocation " Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 13/17] arm64: preserve x18 when CPU is suspended Sami Tolvanen
2019-11-04 13:20     ` Marc Zyngier
2019-11-04 21:38       ` Sami Tolvanen
2019-11-04 21:59         ` Nick Desaulniers
2019-11-05  0:02           ` Sami Tolvanen
2019-11-05 14:55             ` Marc Zyngier
2019-11-01 22:11   ` [PATCH v4 14/17] arm64: efi: restore x18 if it was corrupted Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 15/17] arm64: vdso: disable Shadow Call Stack Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 16/17] arm64: disable SCS for hypervisor code Sami Tolvanen
2019-11-01 22:11   ` [PATCH v4 17/17] arm64: implement Shadow Call Stack Sami Tolvanen
2019-11-05 23:55 ` [PATCH v5 00/14] add support for Clang's " Sami Tolvanen
2019-11-05 23:55   ` [PATCH v5 01/14] arm64: mm: avoid x18 in idmap_kpti_install_ng_mappings Sami Tolvanen
2019-11-05 23:55   ` [PATCH v5 02/14] arm64/lib: copy_page: avoid x18 register in assembler code Sami Tolvanen
2019-11-05 23:55   ` [PATCH v5 03/14] arm64: kvm: stop treating register x18 as caller save Sami Tolvanen
2019-11-05 23:55   ` [PATCH v5 04/14] arm64: kernel: avoid x18 in __cpu_soft_restart Sami Tolvanen
2019-11-05 23:55   ` Sami Tolvanen [this message]
2019-11-15 15:37     ` [PATCH v5 05/14] add support for Clang's Shadow Call Stack (SCS) Mark Rutland
2019-11-15 18:34       ` Sami Tolvanen
2019-11-05 23:56   ` [PATCH v5 06/14] scs: add accounting Sami Tolvanen
2019-11-05 23:56   ` [PATCH v5 07/14] scs: add support for stack usage debugging Sami Tolvanen
2019-11-05 23:56   ` [PATCH v5 08/14] arm64: disable function graph tracing with SCS Sami Tolvanen
2019-11-15 14:18     ` Mark Rutland
2019-11-05 23:56   ` [PATCH v5 09/14] arm64: reserve x18 from general allocation " Sami Tolvanen
2019-11-05 23:56   ` [PATCH v5 10/14] arm64: preserve x18 when CPU is suspended Sami Tolvanen
2019-11-06 20:39     ` Nick Desaulniers
2019-11-15 14:27     ` Mark Rutland
2019-11-05 23:56   ` [PATCH v5 11/14] arm64: efi: restore x18 if it was corrupted Sami Tolvanen
2019-11-06  4:45     ` Miguel Ojeda
2019-11-07 10:51       ` Ard Biesheuvel
2019-11-07 16:26         ` Sami Tolvanen
2019-11-05 23:56   ` [PATCH v5 12/14] arm64: vdso: disable Shadow Call Stack Sami Tolvanen
2019-11-15 14:43     ` Mark Rutland
2019-11-05 23:56   ` [PATCH v5 13/14] arm64: disable SCS for hypervisor code Sami Tolvanen
2019-11-15 14:46     ` Mark Rutland
2019-11-05 23:56   ` [PATCH v5 14/14] arm64: implement Shadow Call Stack Sami Tolvanen
2019-11-15 15:20     ` Mark Rutland
2019-11-15 20:19       ` Sami Tolvanen
2019-11-18 23:13         ` Sami Tolvanen
2019-11-12 23:44   ` [PATCH v5 00/14] add support for Clang's " Kees Cook
2019-11-13 12:03     ` Will Deacon
2019-11-13 18:33       ` Kees Cook
2019-11-15 14:16     ` Mark Rutland

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