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-rw-r--r--arch/x86/entry/calling.h45
-rw-r--r--arch/x86/entry/common.c2
-rw-r--r--arch/x86/entry/entry_64.S4
-rw-r--r--arch/x86/include/asm/asm.h27
-rw-r--r--arch/x86/include/asm/nops.h24
-rw-r--r--arch/x86/include/asm/syscall.h13
-rw-r--r--arch/x86/kernel/cpu/common.c12
-rw-r--r--arch/x86/kernel/head_64.S6
-rw-r--r--arch/x86/kernel/ptrace.c2
-rw-r--r--arch/x86/kernel/signal.c4
10 files changed, 59 insertions, 80 deletions
diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h
index 07a9331d55e7..a4c061fb7c6e 100644
--- a/arch/x86/entry/calling.h
+++ b/arch/x86/entry/calling.h
@@ -6,6 +6,7 @@
#include <asm/percpu.h>
#include <asm/asm-offsets.h>
#include <asm/processor-flags.h>
+#include <asm/ptrace-abi.h>
/*
@@ -62,42 +63,7 @@ For 32-bit we have the following conventions - kernel is built with
* for assembly code:
*/
-/* The layout forms the "struct pt_regs" on the stack: */
-/*
- * C ABI says these regs are callee-preserved. They aren't saved on kernel entry
- * unless syscall needs a complete, fully filled "struct pt_regs".
- */
-#define R15 0*8
-#define R14 1*8
-#define R13 2*8
-#define R12 3*8
-#define RBP 4*8
-#define RBX 5*8
-/* These regs are callee-clobbered. Always saved on kernel entry. */
-#define R11 6*8
-#define R10 7*8
-#define R9 8*8
-#define R8 9*8
-#define RAX 10*8
-#define RCX 11*8
-#define RDX 12*8
-#define RSI 13*8
-#define RDI 14*8
-/*
- * On syscall entry, this is syscall#. On CPU exception, this is error code.
- * On hw interrupt, it's IRQ number:
- */
-#define ORIG_RAX 15*8
-/* Return frame for iretq */
-#define RIP 16*8
-#define CS 17*8
-#define EFLAGS 18*8
-#define RSP 19*8
-#define SS 20*8
-
-#define SIZEOF_PTREGS 21*8
-
-.macro PUSH_AND_CLEAR_REGS rdx=%rdx rax=%rax save_ret=0
+.macro PUSH_REGS rdx=%rdx rax=%rax save_ret=0
.if \save_ret
pushq %rsi /* pt_regs->si */
movq 8(%rsp), %rsi /* temporarily store the return address in %rsi */
@@ -124,7 +90,9 @@ For 32-bit we have the following conventions - kernel is built with
.if \save_ret
pushq %rsi /* return address on top of stack */
.endif
+.endm
+.macro CLEAR_REGS
/*
* Sanitize registers of values that a speculation attack might
* otherwise want to exploit. The lower registers are likely clobbered
@@ -146,6 +114,11 @@ For 32-bit we have the following conventions - kernel is built with
.endm
+.macro PUSH_AND_CLEAR_REGS rdx=%rdx rax=%rax save_ret=0
+ PUSH_REGS rdx=\rdx, rax=\rax, save_ret=\save_ret
+ CLEAR_REGS
+.endm
+
.macro POP_REGS pop_rdi=1 skip_r11rcx=0
popq %r15
popq %r14
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index 04bce95bc7e3..f79688648db1 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -36,7 +36,7 @@
#include <asm/irq_stack.h>
#ifdef CONFIG_X86_64
-__visible noinstr void do_syscall_64(unsigned long nr, struct pt_regs *regs)
+__visible noinstr void do_syscall_64(struct pt_regs *regs, unsigned long nr)
{
add_random_kstack_offset();
nr = syscall_enter_from_user_mode(regs, nr);
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 1886aaf19914..237da6ced61b 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -107,8 +107,8 @@ SYM_INNER_LABEL(entry_SYSCALL_64_after_hwframe, SYM_L_GLOBAL)
PUSH_AND_CLEAR_REGS rax=$-ENOSYS
/* IRQs are off. */
- movq %rax, %rdi
- movq %rsp, %rsi
+ movq %rsp, %rdi
+ movq %rax, %rsi
call do_syscall_64 /* returns with IRQs disabled */
/*
diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
index 0603c7423aca..3ad3da9a7d97 100644
--- a/arch/x86/include/asm/asm.h
+++ b/arch/x86/include/asm/asm.h
@@ -3,25 +3,26 @@
#define _ASM_X86_ASM_H
#ifdef __ASSEMBLY__
-# define __ASM_FORM(x) x
-# define __ASM_FORM_RAW(x) x
-# define __ASM_FORM_COMMA(x) x,
+# define __ASM_FORM(x, ...) x,## __VA_ARGS__
+# define __ASM_FORM_RAW(x, ...) x,## __VA_ARGS__
+# define __ASM_FORM_COMMA(x, ...) x,## __VA_ARGS__,
#else
#include <linux/stringify.h>
-
-# define __ASM_FORM(x) " " __stringify(x) " "
-# define __ASM_FORM_RAW(x) __stringify(x)
-# define __ASM_FORM_COMMA(x) " " __stringify(x) ","
+# define __ASM_FORM(x, ...) " " __stringify(x,##__VA_ARGS__) " "
+# define __ASM_FORM_RAW(x, ...) __stringify(x,##__VA_ARGS__)
+# define __ASM_FORM_COMMA(x, ...) " " __stringify(x,##__VA_ARGS__) ","
#endif
+#define _ASM_BYTES(x, ...) __ASM_FORM(.byte x,##__VA_ARGS__ ;)
+
#ifndef __x86_64__
/* 32 bit */
-# define __ASM_SEL(a,b) __ASM_FORM(a)
-# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a)
+# define __ASM_SEL(a,b) __ASM_FORM(a)
+# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a)
#else
/* 64 bit */
-# define __ASM_SEL(a,b) __ASM_FORM(b)
-# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b)
+# define __ASM_SEL(a,b) __ASM_FORM(b)
+# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b)
#endif
#define __ASM_SIZE(inst, ...) __ASM_SEL(inst##l##__VA_ARGS__, \
@@ -119,6 +120,8 @@
# define CC_OUT(c) [_cc_ ## c] "=qm"
#endif
+#ifdef __KERNEL__
+
/* Exception table entry */
#ifdef __ASSEMBLY__
# define _ASM_EXTABLE_HANDLE(from, to, handler) \
@@ -185,4 +188,6 @@ register unsigned long current_stack_pointer asm(_ASM_SP);
#define ASM_CALL_CONSTRAINT "+r" (current_stack_pointer)
#endif /* __ASSEMBLY__ */
+#endif /* __KERNEL__ */
+
#endif /* _ASM_X86_ASM_H */
diff --git a/arch/x86/include/asm/nops.h b/arch/x86/include/asm/nops.h
index c1e5e818ba16..c5573eaa5bb9 100644
--- a/arch/x86/include/asm/nops.h
+++ b/arch/x86/include/asm/nops.h
@@ -2,6 +2,8 @@
#ifndef _ASM_X86_NOPS_H
#define _ASM_X86_NOPS_H
+#include <asm/asm.h>
+
/*
* Define nops for use with alternative() and for tracing.
*/
@@ -57,20 +59,14 @@
#endif /* CONFIG_64BIT */
-#ifdef __ASSEMBLY__
-#define _ASM_MK_NOP(x) .byte x
-#else
-#define _ASM_MK_NOP(x) ".byte " __stringify(x) "\n"
-#endif
-
-#define ASM_NOP1 _ASM_MK_NOP(BYTES_NOP1)
-#define ASM_NOP2 _ASM_MK_NOP(BYTES_NOP2)
-#define ASM_NOP3 _ASM_MK_NOP(BYTES_NOP3)
-#define ASM_NOP4 _ASM_MK_NOP(BYTES_NOP4)
-#define ASM_NOP5 _ASM_MK_NOP(BYTES_NOP5)
-#define ASM_NOP6 _ASM_MK_NOP(BYTES_NOP6)
-#define ASM_NOP7 _ASM_MK_NOP(BYTES_NOP7)
-#define ASM_NOP8 _ASM_MK_NOP(BYTES_NOP8)
+#define ASM_NOP1 _ASM_BYTES(BYTES_NOP1)
+#define ASM_NOP2 _ASM_BYTES(BYTES_NOP2)
+#define ASM_NOP3 _ASM_BYTES(BYTES_NOP3)
+#define ASM_NOP4 _ASM_BYTES(BYTES_NOP4)
+#define ASM_NOP5 _ASM_BYTES(BYTES_NOP5)
+#define ASM_NOP6 _ASM_BYTES(BYTES_NOP6)
+#define ASM_NOP7 _ASM_BYTES(BYTES_NOP7)
+#define ASM_NOP8 _ASM_BYTES(BYTES_NOP8)
#define ASM_NOP_MAX 8
diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h
index 7cbf733d11af..f6593cafdbd9 100644
--- a/arch/x86/include/asm/syscall.h
+++ b/arch/x86/include/asm/syscall.h
@@ -21,13 +21,12 @@ extern const sys_call_ptr_t sys_call_table[];
#if defined(CONFIG_X86_32)
#define ia32_sys_call_table sys_call_table
-#endif
-
-#if defined(CONFIG_IA32_EMULATION)
+#else
+/*
+ * These may not exist, but still put the prototypes in so we
+ * can use IS_ENABLED().
+ */
extern const sys_call_ptr_t ia32_sys_call_table[];
-#endif
-
-#ifdef CONFIG_X86_X32_ABI
extern const sys_call_ptr_t x32_sys_call_table[];
#endif
@@ -160,7 +159,7 @@ static inline int syscall_get_arch(struct task_struct *task)
? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64;
}
-void do_syscall_64(unsigned long nr, struct pt_regs *regs);
+void do_syscall_64(struct pt_regs *regs, unsigned long nr);
void do_int80_syscall_32(struct pt_regs *regs);
long do_fast_syscall_32(struct pt_regs *regs);
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 212e8bc070da..a99d00393206 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1773,10 +1773,16 @@ void syscall_init(void)
wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL);
#endif
- /* Flags to clear on syscall */
+ /*
+ * Flags to clear on syscall; clear as much as possible
+ * to minimize user space-kernel interference.
+ */
wrmsrl(MSR_SYSCALL_MASK,
- X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|
- X86_EFLAGS_IOPL|X86_EFLAGS_AC|X86_EFLAGS_NT);
+ X86_EFLAGS_CF|X86_EFLAGS_PF|X86_EFLAGS_AF|
+ X86_EFLAGS_ZF|X86_EFLAGS_SF|X86_EFLAGS_TF|
+ X86_EFLAGS_IF|X86_EFLAGS_DF|X86_EFLAGS_OF|
+ X86_EFLAGS_IOPL|X86_EFLAGS_NT|X86_EFLAGS_RF|
+ X86_EFLAGS_AC|X86_EFLAGS_ID);
}
#else /* CONFIG_X86_64 */
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 04bddaaba8e2..d8b3ebd2bb85 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -62,7 +62,7 @@ SYM_CODE_START_NOALIGN(startup_64)
*/
/* Set up the stack for verify_cpu(), similar to initial_stack below */
- leaq (__end_init_task - SIZEOF_PTREGS)(%rip), %rsp
+ leaq (__end_init_task - FRAME_SIZE)(%rip), %rsp
leaq _text(%rip), %rdi
pushq %rsi
@@ -343,10 +343,10 @@ SYM_DATA(initial_vc_handler, .quad handle_vc_boot_ghcb)
#endif
/*
- * The SIZEOF_PTREGS gap is a convention which helps the in-kernel unwinder
+ * The FRAME_SIZE gap is a convention which helps the in-kernel unwinder
* reliably detect the end of the stack.
*/
-SYM_DATA(initial_stack, .quad init_thread_union + THREAD_SIZE - SIZEOF_PTREGS)
+SYM_DATA(initial_stack, .quad init_thread_union + THREAD_SIZE - FRAME_SIZE)
__FINITDATA
__INIT
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 87a4143aa7d7..4c208ea3bd9f 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -911,7 +911,7 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 value)
* syscall with TS_COMPAT still set.
*/
regs->orig_ax = value;
- if (syscall_get_nr(child, regs) >= 0)
+ if (syscall_get_nr(child, regs) != -1)
child->thread_info.status |= TS_I386_REGS_POKED;
break;
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index a06cb107c0e8..e12779a2714d 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -713,7 +713,7 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs)
save_v86_state((struct kernel_vm86_regs *) regs, VM86_SIGNAL);
/* Are we from a system call? */
- if (syscall_get_nr(current, regs) >= 0) {
+ if (syscall_get_nr(current, regs) != -1) {
/* If so, check system call restarting.. */
switch (syscall_get_error(current, regs)) {
case -ERESTART_RESTARTBLOCK:
@@ -793,7 +793,7 @@ void arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal)
}
/* Did we come from a system call? */
- if (syscall_get_nr(current, regs) >= 0) {
+ if (syscall_get_nr(current, regs) != -1) {
/* Restart the system call - no handlers present */
switch (syscall_get_error(current, regs)) {
case -ERESTARTNOHAND: