Merge branch 'uprobes/core' of... (d0616c17) · Commits · e / devices / android_kernel_fairphone_FP5

arch/x86/include/asm/processor.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -759,6 +759,8 @@ static inline void update_debugctlmsr(unsigned long debugctlmsr)
		wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
		}

		extern void set_task_blockstep(struct task_struct *task, bool on);

		/*
		* from system description table in BIOS. Mostly for MCA use, but
		* others may find it useful:

arch/x86/include/asm/uprobes.h

+2 −1

Original line number	Diff line number	Diff line
		@@ -42,10 +42,11 @@ struct arch_uprobe {
		};

		struct arch_uprobe_task {
		unsigned long saved_trap_nr;
		#ifdef CONFIG_X86_64
		unsigned long saved_scratch_register;
		#endif
		unsigned int saved_trap_nr;
		unsigned int saved_tf;
		};

		extern int arch_uprobe_analyze_insn(struct arch_uprobe aup, struct mm_struct mm, unsigned long addr);

arch/x86/kernel/step.c

+33 −20

Original line number	Diff line number	Diff line
		@@ -157,6 +157,33 @@ static int enable_single_step(struct task_struct *child)
		return 1;
		}

		void set_task_blockstep(struct task_struct *task, bool on)
		{
		unsigned long debugctl;

		/*
		* Ensure irq/preemption can't change debugctl in between.
		* Note also that both TIF_BLOCKSTEP and debugctl should
		* be changed atomically wrt preemption.
		* FIXME: this means that set/clear TIF_BLOCKSTEP is simply
		* wrong if task != current, SIGKILL can wakeup the stopped
		* tracee and set/clear can play with the running task, this
		* can confuse the next __switch_to_xtra().
		*/
		local_irq_disable();
		debugctl = get_debugctlmsr();
		if (on) {
		debugctl \|= DEBUGCTLMSR_BTF;
		set_tsk_thread_flag(task, TIF_BLOCKSTEP);
		} else {
		debugctl &= ~DEBUGCTLMSR_BTF;
		clear_tsk_thread_flag(task, TIF_BLOCKSTEP);
		}
		if (task == current)
		update_debugctlmsr(debugctl);
		local_irq_enable();
		}

		/*
		* Enable single or block step.
		*/
		@@ -169,19 +196,10 @@ static void enable_step(struct task_struct *child, bool block)
		* So no one should try to use debugger block stepping in a program
		* that uses user-mode single stepping itself.
		*/
		if (enable_single_step(child) && block) {
		unsigned long debugctl = get_debugctlmsr();

		debugctl \|= DEBUGCTLMSR_BTF;
		update_debugctlmsr(debugctl);
		set_tsk_thread_flag(child, TIF_BLOCKSTEP);
		} else if (test_tsk_thread_flag(child, TIF_BLOCKSTEP)) {
		unsigned long debugctl = get_debugctlmsr();

		debugctl &= ~DEBUGCTLMSR_BTF;
		update_debugctlmsr(debugctl);
		clear_tsk_thread_flag(child, TIF_BLOCKSTEP);
		}
		if (enable_single_step(child) && block)
		set_task_blockstep(child, true);
		else if (test_tsk_thread_flag(child, TIF_BLOCKSTEP))
		set_task_blockstep(child, false);
		}

		void user_enable_single_step(struct task_struct *child)
		@@ -199,13 +217,8 @@ void user_disable_single_step(struct task_struct *child)
		/*
		* Make sure block stepping (BTF) is disabled.
		*/
		if (test_tsk_thread_flag(child, TIF_BLOCKSTEP)) {
		unsigned long debugctl = get_debugctlmsr();

		debugctl &= ~DEBUGCTLMSR_BTF;
		update_debugctlmsr(debugctl);
		clear_tsk_thread_flag(child, TIF_BLOCKSTEP);
		}
		if (test_tsk_thread_flag(child, TIF_BLOCKSTEP))
		set_task_blockstep(child, false);

		/* Always clear TIF_SINGLESTEP... */
		clear_tsk_thread_flag(child, TIF_SINGLESTEP);

arch/x86/kernel/uprobes.c

+51 −1

Original line number	Diff line number	Diff line
		@@ -41,6 +41,9 @@
		/* Adjust the return address of a call insn */
		#define UPROBE_FIX_CALL 0x2

		/* Instruction will modify TF, don't change it */
		#define UPROBE_FIX_SETF 0x4

		#define UPROBE_FIX_RIP_AX 0x8000
		#define UPROBE_FIX_RIP_CX 0x4000

		@@ -239,6 +242,10 @@ static void prepare_fixups(struct arch_uprobe auprobe, struct insn insn)
		insn_get_opcode(insn); /* should be a nop */

		switch (OPCODE1(insn)) {
		case 0x9d:
		/* popf */
		auprobe->fixups \|= UPROBE_FIX_SETF;
		break;
		case 0xc3: /* ret/lret */
		case 0xcb:
		case 0xc2:
		@@ -646,7 +653,7 @@ void arch_uprobe_abort_xol(struct arch_uprobe auprobe, struct pt_regs regs)
		* Skip these instructions as per the currently known x86 ISA.
		* 0x66* { 0x90 \| 0x0f 0x1f \| 0x0f 0x19 \| 0x87 0xc0 }
		*/
		bool arch_uprobe_skip_sstep(struct arch_uprobe auprobe, struct pt_regs regs)
		static bool __skip_sstep(struct arch_uprobe auprobe, struct pt_regs regs)
		{
		int i;

		@@ -673,3 +680,46 @@ bool arch_uprobe_skip_sstep(struct arch_uprobe auprobe, struct pt_regs regs)
		}
		return false;
		}

		bool arch_uprobe_skip_sstep(struct arch_uprobe auprobe, struct pt_regs regs)
		{
		bool ret = __skip_sstep(auprobe, regs);
		if (ret && (regs->flags & X86_EFLAGS_TF))
		send_sig(SIGTRAP, current, 0);
		return ret;
		}

		void arch_uprobe_enable_step(struct arch_uprobe *auprobe)
		{
		struct task_struct *task = current;
		struct arch_uprobe_task *autask = &task->utask->autask;
		struct pt_regs *regs = task_pt_regs(task);

		autask->saved_tf = !!(regs->flags & X86_EFLAGS_TF);

		regs->flags \|= X86_EFLAGS_TF;
		if (test_tsk_thread_flag(task, TIF_BLOCKSTEP))
		set_task_blockstep(task, false);
		}

		void arch_uprobe_disable_step(struct arch_uprobe *auprobe)
		{
		struct task_struct *task = current;
		struct arch_uprobe_task *autask = &task->utask->autask;
		bool trapped = (task->utask->state == UTASK_SSTEP_TRAPPED);
		struct pt_regs *regs = task_pt_regs(task);
		/*
		* The state of TIF_BLOCKSTEP was not saved so we can get an extra
		* SIGTRAP if we do not clear TF. We need to examine the opcode to
		* make it right.
		*/
		if (unlikely(trapped)) {
		if (!autask->saved_tf)
		regs->flags &= ~X86_EFLAGS_TF;
		} else {
		if (autask->saved_tf)
		send_sig(SIGTRAP, task, 0);
		else if (!(auprobe->fixups & UPROBE_FIX_SETF))
		regs->flags &= ~X86_EFLAGS_TF;
		}
		}

include/linux/sched.h

+2 −1

Original line number	Diff line number	Diff line
		@@ -446,7 +446,8 @@ extern int get_dumpable(struct mm_struct *mm);
		#define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */
		#define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */

		#define MMF_HAS_UPROBES 19 /* might have uprobes */
		#define MMF_HAS_UPROBES 19 /* has uprobes */
		#define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */

		#define MMF_INIT_MASK (MMF_DUMPABLE_MASK \| MMF_DUMP_FILTER_MASK)