linux/arch/x86/lib/retpoline.S
Masami Hiramatsu c1804a2368 kprobes/x86: Blacklist indirect thunk functions for kprobes
Mark __x86_indirect_thunk_* functions as blacklist for kprobes
because those functions can be called from anywhere in the kernel
including blacklist functions of kprobes.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/151629209111.10241.5444852823378068683.stgit@devbox
2018-01-19 16:31:28 +01:00

50 lines
1.2 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/stringify.h>
#include <linux/linkage.h>
#include <asm/dwarf2.h>
#include <asm/cpufeatures.h>
#include <asm/alternative-asm.h>
#include <asm/export.h>
#include <asm/nospec-branch.h>
.macro THUNK reg
.section .text.__x86.indirect_thunk
ENTRY(__x86_indirect_thunk_\reg)
CFI_STARTPROC
JMP_NOSPEC %\reg
CFI_ENDPROC
ENDPROC(__x86_indirect_thunk_\reg)
.endm
/*
* Despite being an assembler file we can't just use .irp here
* because __KSYM_DEPS__ only uses the C preprocessor and would
* only see one instance of "__x86_indirect_thunk_\reg" rather
* than one per register with the correct names. So we do it
* the simple and nasty way...
*/
#define __EXPORT_THUNK(sym) _ASM_NOKPROBE(sym); EXPORT_SYMBOL(sym)
#define EXPORT_THUNK(reg) __EXPORT_THUNK(__x86_indirect_thunk_ ## reg)
#define GENERATE_THUNK(reg) THUNK reg ; EXPORT_THUNK(reg)
GENERATE_THUNK(_ASM_AX)
GENERATE_THUNK(_ASM_BX)
GENERATE_THUNK(_ASM_CX)
GENERATE_THUNK(_ASM_DX)
GENERATE_THUNK(_ASM_SI)
GENERATE_THUNK(_ASM_DI)
GENERATE_THUNK(_ASM_BP)
GENERATE_THUNK(_ASM_SP)
#ifdef CONFIG_64BIT
GENERATE_THUNK(r8)
GENERATE_THUNK(r9)
GENERATE_THUNK(r10)
GENERATE_THUNK(r11)
GENERATE_THUNK(r12)
GENERATE_THUNK(r13)
GENERATE_THUNK(r14)
GENERATE_THUNK(r15)
#endif