From 4979fb53ab0ed35eddd20a73c25a5597bc22a57f Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 21 Jan 2020 15:53:09 +0100 Subject: x86/int3: Ensure that poke_int3_handler() is not traced In order to ensure poke_int3_handler() is completely self contained -- this is called while modifying other text, imagine the fun of hitting another INT3 -- ensure that everything it uses is not traced. The primary means here is to force inlining; bsearch() is notrace because all of lib/ is. Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Reviewed-by: Alexandre Chartre Acked-by: Andy Lutomirski Link: https://lkml.kernel.org/r/20200505135313.410702173@linutronix.de --- arch/x86/include/asm/ptrace.h | 2 +- arch/x86/include/asm/text-patching.h | 11 +++++++---- 2 files changed, 8 insertions(+), 5 deletions(-) (limited to 'arch/x86/include') diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index 6d6475fdd327..ebedeab48704 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -123,7 +123,7 @@ static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc) * On x86_64, vm86 mode is mercifully nonexistent, and we don't need * the extra check. */ -static inline int user_mode(struct pt_regs *regs) +static __always_inline int user_mode(struct pt_regs *regs) { #ifdef CONFIG_X86_32 return ((regs->cs & SEGMENT_RPL_MASK) | (regs->flags & X86_VM_MASK)) >= USER_RPL; diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h index 67315fa3956a..6593b42cb379 100644 --- a/arch/x86/include/asm/text-patching.h +++ b/arch/x86/include/asm/text-patching.h @@ -64,7 +64,7 @@ extern void text_poke_finish(void); #define DISP32_SIZE 4 -static inline int text_opcode_size(u8 opcode) +static __always_inline int text_opcode_size(u8 opcode) { int size = 0; @@ -118,12 +118,14 @@ extern __ro_after_init struct mm_struct *poking_mm; extern __ro_after_init unsigned long poking_addr; #ifndef CONFIG_UML_X86 -static inline void int3_emulate_jmp(struct pt_regs *regs, unsigned long ip) +static __always_inline +void int3_emulate_jmp(struct pt_regs *regs, unsigned long ip) { regs->ip = ip; } -static inline void int3_emulate_push(struct pt_regs *regs, unsigned long val) +static __always_inline +void int3_emulate_push(struct pt_regs *regs, unsigned long val) { /* * The int3 handler in entry_64.S adds a gap between the @@ -138,7 +140,8 @@ static inline void int3_emulate_push(struct pt_regs *regs, unsigned long val) *(unsigned long *)regs->sp = val; } -static inline void int3_emulate_call(struct pt_regs *regs, unsigned long func) +static __always_inline +void int3_emulate_call(struct pt_regs *regs, unsigned long func) { int3_emulate_push(regs, regs->ip - INT3_INSN_SIZE + CALL_INSN_SIZE); int3_emulate_jmp(regs, func); -- cgit v1.2.3