diff options
Diffstat (limited to 'arch/x86/kernel/kprobes_32.c')
-rw-r--r-- | arch/x86/kernel/kprobes_32.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/x86/kernel/kprobes_32.c b/arch/x86/kernel/kprobes_32.c index 3a020f7..bc4a683 100644 --- a/arch/x86/kernel/kprobes_32.c +++ b/arch/x86/kernel/kprobes_32.c @@ -217,8 +217,21 @@ static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs, kcb->kprobe_saved_eflags &= ~IF_MASK; } +static __always_inline void clear_btf(void) +{ + if (test_thread_flag(TIF_DEBUGCTLMSR)) + wrmsr(MSR_IA32_DEBUGCTLMSR, 0, 0); +} + +static __always_inline void restore_btf(void) +{ + if (test_thread_flag(TIF_DEBUGCTLMSR)) + wrmsr(MSR_IA32_DEBUGCTLMSR, current->thread.debugctlmsr, 0); +} + static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs) { + clear_btf(); regs->eflags |= TF_MASK; regs->eflags &= ~IF_MASK; /*single step inline if the instruction is an int3*/ @@ -542,6 +555,8 @@ static void __kprobes resume_execution(struct kprobe *p, regs->eip = orig_eip + (regs->eip - copy_eip); no_change: + restore_btf(); + return; } |