Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a539f5d4 authored by Jon Medhurst's avatar Jon Medhurst Committed by Nicolas Pitre
Browse files

ARM: kprobes: Remove redundant condition checks from simulation routines 



Now we have the framework code handling conditionally executed
instructions we can remove redundant checks in individual simulation
routines.

Signed-off-by: default avatarJon Medhurst <tixy@yxit.co.uk>
Signed-off-by: default avatarNicolas Pitre <nicolas.pitre@linaro.org>
parent 073090cb

arch/arm/kernel/kprobes-decode.c

+3 −27
Original line number Original line Diff line number Diff line
@@ -71,10 +71,6 @@ 
#define PSR_fs	(PSR_f|PSR_s)

#define PSR_fs	(PSR_f|PSR_s)





#define KPROBE_RETURN_INSTRUCTION	0xe1a0f00e	/* mov pc, lr */

#define KPROBE_RETURN_INSTRUCTION	0xe1a0f00e	/* mov pc, lr */

#define SET_R0_TRUE_INSTRUCTION		0xe3a00001	/* mov	r0, #1 */



#define	truecc_insn(insn)	(((insn) & 0xf0000000) | \

				 (SET_R0_TRUE_INSTRUCTION & 0x0fffffff))





typedef long (insn_0arg_fn_t)(void);

typedef long (insn_0arg_fn_t)(void);

typedef long (insn_1arg_fn_t)(long);

typedef long (insn_1arg_fn_t)(long);
@@ -419,14 +415,10 @@ insnslot_llret_4arg_rwflags(long r0, long r1, long r2, long r3, long *cpsr, 




static void __kprobes simulate_bbl(struct kprobe *p, struct pt_regs *regs)

static void __kprobes simulate_bbl(struct kprobe *p, struct pt_regs *regs)

{

{

	insn_1arg_fn_t *i_fn = (insn_1arg_fn_t *)&p->ainsn.insn[0];

	kprobe_opcode_t insn = p->opcode;

	kprobe_opcode_t insn = p->opcode;

	long iaddr = (long)p->addr;

	long iaddr = (long)p->addr;

	int disp  = branch_displacement(insn);

	int disp  = branch_displacement(insn);





	if (!insnslot_1arg_rflags(0, regs->ARM_cpsr, i_fn))

		return;



	if (insn & (1 << 24))

	if (insn & (1 << 24))

		regs->ARM_lr = iaddr + 4;

		regs->ARM_lr = iaddr + 4;
@@ -446,14 +438,10 @@ static void __kprobes simulate_blx1(struct kprobe *p, struct pt_regs *regs) 




static void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs)

static void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs)

{

{

	insn_1arg_fn_t *i_fn = (insn_1arg_fn_t *)&p->ainsn.insn[0];

	kprobe_opcode_t insn = p->opcode;

	kprobe_opcode_t insn = p->opcode;

	int rm = insn & 0xf;

	int rm = insn & 0xf;

	long rmv = regs->uregs[rm];

	long rmv = regs->uregs[rm];





	if (!insnslot_1arg_rflags(0, regs->ARM_cpsr, i_fn))

		return;



	if (insn & (1 << 5))

	if (insn & (1 << 5))

		regs->ARM_lr = (long)p->addr + 4;

		regs->ARM_lr = (long)p->addr + 4;
@@ -465,7 +453,6 @@ static void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs) 




static void __kprobes simulate_ldm1stm1(struct kprobe *p, struct pt_regs *regs)

static void __kprobes simulate_ldm1stm1(struct kprobe *p, struct pt_regs *regs)

{

{

	insn_1arg_fn_t *i_fn = (insn_1arg_fn_t *)&p->ainsn.insn[0];

	kprobe_opcode_t insn = p->opcode;

	kprobe_opcode_t insn = p->opcode;

	int rn = (insn >> 16) & 0xf;

	int rn = (insn >> 16) & 0xf;

	int lbit = insn & (1 << 20);

	int lbit = insn & (1 << 20);
@@ -476,9 +463,6 @@ static void __kprobes simulate_ldm1stm1(struct kprobe *p, struct pt_regs *regs) 
	int reg_bit_vector;

	int reg_bit_vector;

	int reg_count;

	int reg_count;





	if (!insnslot_1arg_rflags(0, regs->ARM_cpsr, i_fn))

		return;



	reg_count = 0;

	reg_count = 0;

	reg_bit_vector = insn & 0xffff;

	reg_bit_vector = insn & 0xffff;

	while (reg_bit_vector) {

	while (reg_bit_vector) {
@@ -510,11 +494,6 @@ static void __kprobes simulate_ldm1stm1(struct kprobe *p, struct pt_regs *regs) 




static void __kprobes simulate_stm1_pc(struct kprobe *p, struct pt_regs *regs)

static void __kprobes simulate_stm1_pc(struct kprobe *p, struct pt_regs *regs)

{

{

	insn_1arg_fn_t *i_fn = (insn_1arg_fn_t *)&p->ainsn.insn[0];



	if (!insnslot_1arg_rflags(0, regs->ARM_cpsr, i_fn))

		return;



	regs->ARM_pc = (long)p->addr + str_pc_offset;

	regs->ARM_pc = (long)p->addr + str_pc_offset;

	simulate_ldm1stm1(p, regs);

	simulate_ldm1stm1(p, regs);

	regs->ARM_pc = (long)p->addr + 4;

	regs->ARM_pc = (long)p->addr + 4;
@@ -1056,9 +1035,8 @@ space_cccc_000x(kprobe_opcode_t insn, struct arch_specific_insn *asi) 
		/* BLX(2) : cccc 0001 0010 xxxx xxxx xxxx 0011 xxxx */

		/* BLX(2) : cccc 0001 0010 xxxx xxxx xxxx 0011 xxxx */

		/* BX     : cccc 0001 0010 xxxx xxxx xxxx 0001 xxxx */

		/* BX     : cccc 0001 0010 xxxx xxxx xxxx 0001 xxxx */

		if ((insn & 0x0ff000d0) == 0x01200010) {

		if ((insn & 0x0ff000d0) == 0x01200010) {

			asi->insn[0] = truecc_insn(insn);

			asi->insn_handler = simulate_blx2bx;

			asi->insn_handler = simulate_blx2bx;

			return INSN_GOOD;

			return INSN_GOOD_NO_SLOT;

		}

		}





		/* CLZ : cccc 0001 0110 xxxx xxxx xxxx 0001 xxxx */

		/* CLZ : cccc 0001 0110 xxxx xxxx xxxx 0001 xxxx */
@@ -1333,10 +1311,9 @@ space_cccc_100x(kprobe_opcode_t insn, struct arch_specific_insn *asi) 




	/* LDM(1) : cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */

	/* LDM(1) : cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */

	/* STM(1) : cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */

	/* STM(1) : cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */

	asi->insn[0] = truecc_insn(insn);

	asi->insn_handler = ((insn & 0x108000) == 0x008000) ? /* STM & R15 */

	asi->insn_handler = ((insn & 0x108000) == 0x008000) ? /* STM & R15 */

				simulate_stm1_pc : simulate_ldm1stm1;

				simulate_stm1_pc : simulate_ldm1stm1;

	return INSN_GOOD;

	return INSN_GOOD_NO_SLOT;

}

}





static enum kprobe_insn __kprobes

static enum kprobe_insn __kprobes
@@ -1344,9 +1321,8 @@ space_cccc_101x(kprobe_opcode_t insn, struct arch_specific_insn *asi) 
{

{

	/* B  : cccc 1010 xxxx xxxx xxxx xxxx xxxx xxxx */

	/* B  : cccc 1010 xxxx xxxx xxxx xxxx xxxx xxxx */

	/* BL : cccc 1011 xxxx xxxx xxxx xxxx xxxx xxxx */

	/* BL : cccc 1011 xxxx xxxx xxxx xxxx xxxx xxxx */

	asi->insn[0] = truecc_insn(insn);

	asi->insn_handler = simulate_bbl;

	asi->insn_handler = simulate_bbl;

	return INSN_GOOD;

	return INSN_GOOD_NO_SLOT;

}

}





static enum kprobe_insn __kprobes

static enum kprobe_insn __kprobes