diff options
| -rw-r--r-- | arch/arm/include/asm/probes.h | 1 | ||||
| -rw-r--r-- | arch/arm/probes/decode.c | 10 | ||||
| -rw-r--r-- | arch/arm/probes/kprobes/Makefile | 6 | ||||
| -rw-r--r-- | arch/arm/probes/kprobes/actions-arm.c | 3 | ||||
| -rw-r--r-- | arch/arm/probes/kprobes/actions-thumb.c | 5 | ||||
| -rw-r--r-- | arch/arm/probes/kprobes/checkers-arm.c | 99 | ||||
| -rw-r--r-- | arch/arm/probes/kprobes/checkers-common.c | 101 | ||||
| -rw-r--r-- | arch/arm/probes/kprobes/checkers-thumb.c | 110 | ||||
| -rw-r--r-- | arch/arm/probes/kprobes/checkers.h | 54 |
9 files changed, 383 insertions, 6 deletions
diff --git a/arch/arm/include/asm/probes.h b/arch/arm/include/asm/probes.h index 806cfe622a9e..6026deb28794 100644 --- a/arch/arm/include/asm/probes.h +++ b/arch/arm/include/asm/probes.h @@ -38,6 +38,7 @@ struct arch_probes_insn { probes_check_cc *insn_check_cc; probes_insn_singlestep_t *insn_singlestep; probes_insn_fn_t *insn_fn; + int stack_space; }; #endif diff --git a/arch/arm/probes/decode.c b/arch/arm/probes/decode.c index c7d442018902..f9d7c423f2cc 100644 --- a/arch/arm/probes/decode.c +++ b/arch/arm/probes/decode.c @@ -425,6 +425,16 @@ probes_decode_insn(probes_opcode_t insn, struct arch_probes_insn *asi, */ probes_opcode_t origin_insn = insn; + /* + * stack_space is initialized to 0 here. Checker functions + * should update is value if they find this is a stack store + * instruction: positive value means bytes of stack usage, + * negitive value means unable to determine stack usage + * statically. For instruction doesn't store to stack, checker + * do nothing with it. + */ + asi->stack_space = 0; + if (emulate) insn = prepare_emulated_insn(insn, asi, thumb); diff --git a/arch/arm/probes/kprobes/Makefile b/arch/arm/probes/kprobes/Makefile index eb38a428ecd6..bc8d504c3d78 100644 --- a/arch/arm/probes/kprobes/Makefile +++ b/arch/arm/probes/kprobes/Makefile @@ -1,11 +1,11 @@ -obj-$(CONFIG_KPROBES) += core.o actions-common.o +obj-$(CONFIG_KPROBES) += core.o actions-common.o checkers-common.o obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o test-kprobes-objs := test-core.o ifdef CONFIG_THUMB2_KERNEL -obj-$(CONFIG_KPROBES) += actions-thumb.o +obj-$(CONFIG_KPROBES) += actions-thumb.o checkers-thumb.o test-kprobes-objs += test-thumb.o else -obj-$(CONFIG_KPROBES) += actions-arm.o +obj-$(CONFIG_KPROBES) += actions-arm.o checkers-arm.o test-kprobes-objs += test-arm.o endif diff --git a/arch/arm/probes/kprobes/actions-arm.c b/arch/arm/probes/kprobes/actions-arm.c index fbd93a9ada75..06988ef7eeb7 100644 --- a/arch/arm/probes/kprobes/actions-arm.c +++ b/arch/arm/probes/kprobes/actions-arm.c @@ -64,6 +64,7 @@ #include "../decode-arm.h" #include "core.h" +#include "checkers.h" #if __LINUX_ARM_ARCH__ >= 6 #define BLX(reg) "blx "reg" \n\t" @@ -340,4 +341,4 @@ const union decode_action kprobes_arm_actions[NUM_PROBES_ARM_ACTIONS] = { [PROBES_LDMSTM] = {.decoder = kprobe_decode_ldmstm} }; -const struct decode_checker *kprobes_arm_checkers[] = {NULL}; +const struct decode_checker *kprobes_arm_checkers[] = {arm_stack_checker, NULL}; diff --git a/arch/arm/probes/kprobes/actions-thumb.c b/arch/arm/probes/kprobes/actions-thumb.c index 2796121fe90e..07cfd9bef340 100644 --- a/arch/arm/probes/kprobes/actions-thumb.c +++ b/arch/arm/probes/kprobes/actions-thumb.c @@ -15,6 +15,7 @@ #include "../decode-thumb.h" #include "core.h" +#include "checkers.h" /* These emulation encodings are functionally equivalent... */ #define t32_emulate_rd8rn16rm0ra12_noflags \ @@ -665,5 +666,5 @@ const union decode_action kprobes_t32_actions[NUM_PROBES_T32_ACTIONS] = { .handler = t32_emulate_rdlo12rdhi8rn16rm0_noflags}, }; -const struct decode_checker *kprobes_t32_checkers[] = {NULL}; -const struct decode_checker *kprobes_t16_checkers[] = {NULL}; +const struct decode_checker *kprobes_t32_checkers[] = {t32_stack_checker, NULL}; +const struct decode_checker *kprobes_t16_checkers[] = {t16_stack_checker, NULL}; diff --git a/arch/arm/probes/kprobes/checkers-arm.c b/arch/arm/probes/kprobes/checkers-arm.c new file mode 100644 index 000000000000..f8176631d2a5 --- /dev/null +++ b/arch/arm/probes/kprobes/checkers-arm.c @@ -0,0 +1,99 @@ +/* + * arch/arm/probes/kprobes/checkers-arm.c + * + * Copyright (C) 2014 Huawei Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#include <linux/kernel.h> +#include "../decode.h" +#include "../decode-arm.h" +#include "checkers.h" + +static enum probes_insn __kprobes arm_check_stack(probes_opcode_t insn, + struct arch_probes_insn *asi, + const struct decode_header *h) +{ + /* + * PROBES_LDRSTRD, PROBES_LDMSTM, PROBES_STORE, + * PROBES_STORE_EXTRA may get here. Simply mark all normal + * insns as STACK_USE_NONE. + */ + static const union decode_item table[] = { + /* + * 'STR{,D,B,H}, Rt, [Rn, Rm]' should be marked as UNKNOWN + * if Rn or Rm is SP. + * x + * STR (register) cccc 011x x0x0 xxxx xxxx xxxx xxxx xxxx + * STRB (register) cccc 011x x1x0 xxxx xxxx xxxx xxxx xxxx + */ + DECODE_OR (0x0e10000f, 0x0600000d), + DECODE_OR (0x0e1f0000, 0x060d0000), + + /* + * x + * STRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1111 xxxx + * STRH (register) cccc 000x x0x0 xxxx xxxx xxxx 1011 xxxx + */ + DECODE_OR (0x0e5000bf, 0x000000bd), + DECODE_CUSTOM (0x0e5f00b0, 0x000d00b0, STACK_USE_UNKNOWN), + + /* + * For PROBES_LDMSTM, only stmdx sp, [...] need to examine + * + * Bit B/A (bit 24) encodes arithmetic operation order. 1 means + * before, 0 means after. + * Bit I/D (bit 23) encodes arithmetic operation. 1 means + * increment, 0 means decrement. + * + * So: + * B I + * / / + * A D | Rn | + * STMDX SP, [...] cccc 100x 00x0 xxxx xxxx xxxx xxxx xxxx + */ + DECODE_CUSTOM (0x0edf0000, 0x080d0000, STACK_USE_STMDX), + + /* P U W | Rn | Rt | imm12 |*/ + /* STR (immediate) cccc 010x x0x0 1101 xxxx xxxx xxxx xxxx */ + /* STRB (immediate) cccc 010x x1x0 1101 xxxx xxxx xxxx xxxx */ + /* P U W | Rn | Rt |imm4| |imm4|*/ + /* STRD (immediate) cccc 000x x1x0 1101 xxxx xxxx 1111 xxxx */ + /* STRH (immediate) cccc 000x x1x0 1101 xxxx xxxx 1011 xxxx */ + /* + * index = (P == '1'); add = (U == '1'). + * Above insns with: + * index == 0 (str{,d,h} rx, [sp], #+/-imm) or + * add == 1 (str{,d,h} rx, [sp, #+<imm>]) + * should be STACK_USE_NONE. + * Only str{,b,d,h} rx,[sp,#-n] (P == 1 and U == 0) are + * required to be examined. + */ + /* STR{,B} Rt,[SP,#-n] cccc 0101 0xx0 1101 xxxx xxxx xxxx xxxx */ + DECODE_CUSTOM (0x0f9f0000, 0x050d0000, STACK_USE_FIXED_XXX), + + /* STR{D,H} Rt,[SP,#-n] cccc 0001 01x0 1101 xxxx xxxx 1x11 xxxx */ + DECODE_CUSTOM (0x0fdf00b0, 0x014d00b0, STACK_USE_FIXED_X0X), + + /* fall through */ + DECODE_CUSTOM (0, 0, STACK_USE_NONE), + DECODE_END + }; + + return probes_decode_insn(insn, asi, table, false, false, stack_check_actions, NULL); +} + +const struct decode_checker arm_stack_checker[NUM_PROBES_ARM_ACTIONS] = { + [PROBES_LDRSTRD] = {.checker = arm_check_stack}, + [PROBES_STORE_EXTRA] = {.checker = arm_check_stack}, + [PROBES_STORE] = {.checker = arm_check_stack}, + [PROBES_LDMSTM] = {.checker = arm_check_stack}, +}; diff --git a/arch/arm/probes/kprobes/checkers-common.c b/arch/arm/probes/kprobes/checkers-common.c new file mode 100644 index 000000000000..971119c29474 --- /dev/null +++ b/arch/arm/probes/kprobes/checkers-common.c @@ -0,0 +1,101 @@ +/* + * arch/arm/probes/kprobes/checkers-common.c + * + * Copyright (C) 2014 Huawei Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#include <linux/kernel.h> +#include "../decode.h" +#include "../decode-arm.h" +#include "checkers.h" + +enum probes_insn checker_stack_use_none(probes_opcode_t insn, + struct arch_probes_insn *asi, + const struct decode_header *h) +{ + asi->stack_space = 0; + return INSN_GOOD_NO_SLOT; +} + +enum probes_insn checker_stack_use_unknown(probes_opcode_t insn, + struct arch_probes_insn *asi, + const struct decode_header *h) +{ + asi->stack_space = -1; + return INSN_GOOD_NO_SLOT; +} + +#ifdef CONFIG_THUMB2_KERNEL +enum probes_insn checker_stack_use_imm_0xx(probes_opcode_t insn, + struct arch_probes_insn *asi, + const struct decode_header *h) +{ + int imm = insn & 0xff; + asi->stack_space = imm; + return INSN_GOOD_NO_SLOT; +} + +/* + * Different from other insn uses imm8, the real addressing offset of + * STRD in T32 encoding should be imm8 * 4. See ARMARM description. + */ +enum probes_insn checker_stack_use_t32strd(probes_opcode_t insn, + struct arch_probes_insn *asi, + const struct decode_header *h) +{ + int imm = insn & 0xff; + asi->stack_space = imm << 2; + return INSN_GOOD_NO_SLOT; +} +#else +enum probes_insn checker_stack_use_imm_x0x(probes_opcode_t insn, + struct arch_probes_insn *asi, + const struct decode_header *h) +{ + int imm = ((insn & 0xf00) >> 4) + (insn & 0xf); + asi->stack_space = imm; + return INSN_GOOD_NO_SLOT; +} +#endif + +enum probes_insn checker_stack_use_imm_xxx(probes_opcode_t insn, + struct arch_probes_insn *asi, + const struct decode_header *h) +{ + int imm = insn & 0xfff; + asi->stack_space = imm; + return INSN_GOOD_NO_SLOT; +} + +enum probes_insn checker_stack_use_stmdx(probes_opcode_t insn, + struct arch_probes_insn *asi, + const struct decode_header *h) +{ + unsigned int reglist = insn & 0xffff; + int pbit = insn & (1 << 24); + asi->stack_space = (hweight32(reglist) - (!pbit ? 1 : 0)) * 4; + + return INSN_GOOD_NO_SLOT; +} + +const union decode_action stack_check_actions[] = { + [STACK_USE_NONE] = {.decoder = checker_stack_use_none}, + [STACK_USE_UNKNOWN] = {.decoder = checker_stack_use_unknown}, +#ifdef CONFIG_THUMB2_KERNEL + [STACK_USE_FIXED_0XX] = {.decoder = checker_stack_use_imm_0xx}, + [STACK_USE_T32STRD] = {.decoder = checker_stack_use_t32strd}, +#else + [STACK_USE_FIXED_X0X] = {.decoder = checker_stack_use_imm_x0x}, +#endif + [STACK_USE_FIXED_XXX] = {.decoder = checker_stack_use_imm_xxx}, + [STACK_USE_STMDX] = {.decoder = checker_stack_use_stmdx}, +}; diff --git a/arch/arm/probes/kprobes/checkers-thumb.c b/arch/arm/probes/kprobes/checkers-thumb.c new file mode 100644 index 000000000000..d608e3b9017a --- /dev/null +++ b/arch/arm/probes/kprobes/checkers-thumb.c @@ -0,0 +1,110 @@ +/* + * arch/arm/probes/kprobes/checkers-thumb.c + * + * Copyright (C) 2014 Huawei Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#include <linux/kernel.h> +#include "../decode.h" +#include "../decode-thumb.h" +#include "checkers.h" + +static enum probes_insn __kprobes t32_check_stack(probes_opcode_t insn, + struct arch_probes_insn *asi, + const struct decode_header *h) +{ + /* + * PROBES_T32_LDMSTM, PROBES_T32_LDRDSTRD and PROBES_T32_LDRSTR + * may get here. Simply mark all normal insns as STACK_USE_NONE. + */ + static const union decode_item table[] = { + + /* + * First, filter out all ldr insns to make our life easier. + * Following load insns may come here: + * LDM, LDRD, LDR. + * In T32 encoding, bit 20 is enough for distinguishing + * load and store. All load insns have this bit set, when + * all store insns have this bit clear. + */ + DECODE_CUSTOM (0x00100000, 0x00100000, STACK_USE_NONE), + + /* + * Mark all 'STR{,B,H}, Rt, [Rn, Rm]' as STACK_USE_UNKNOWN + * if Rn or Rm is SP. T32 doesn't encode STRD. + */ + /* xx | Rn | Rt | | Rm |*/ + /* STR (register) 1111 1000 0100 xxxx xxxx 0000 00xx xxxx */ + /* STRB (register) 1111 1000 0000 xxxx xxxx 0000 00xx xxxx */ + /* STRH (register) 1111 1000 0010 xxxx xxxx 0000 00xx xxxx */ + /* INVALID INSN 1111 1000 0110 xxxx xxxx 0000 00xx xxxx */ + /* By Introducing INVALID INSN, bit 21 and 22 can be ignored. */ + DECODE_OR (0xff9f0fc0, 0xf80d0000), + DECODE_CUSTOM (0xff900fcf, 0xf800000d, STACK_USE_UNKNOWN), + + + /* xx | Rn | Rt | PUW| imm8 |*/ + /* STR (imm 8) 1111 1000 0100 1101 xxxx 110x xxxx xxxx */ + /* STRB (imm 8) 1111 1000 0000 1101 xxxx 110x xxxx xxxx */ + /* STRH (imm 8) 1111 1000 0010 1101 xxxx 110x xxxx xxxx */ + /* INVALID INSN 1111 1000 0110 1101 xxxx 110x xxxx xxxx */ + /* Only consider U == 0 and P == 1: strx rx, [sp, #-<imm>] */ + DECODE_CUSTOM (0xff9f0e00, 0xf80d0c00, STACK_USE_FIXED_0XX), + + /* For STR{,B,H} (imm 12), offset is always positive, so ignore them. */ + + /* P U W | Rn | Rt | Rt2| imm8 |*/ + /* STRD (immediate) 1110 1001 01x0 1101 xxxx xxxx xxxx xxxx */ + /* + * Only consider U == 0 and P == 1. + * Also note that STRD in T32 encoding is special: + * imm = ZeroExtend(imm8:'00', 32) + */ + DECODE_CUSTOM (0xffdf0000, 0xe94d0000, STACK_USE_T32STRD), + + /* | Rn | */ + /* STMDB 1110 1001 00x0 1101 xxxx xxxx xxxx xxxx */ + DECODE_CUSTOM (0xffdf0000, 0xe90d0000, STACK_USE_STMDX), + + /* fall through */ + DECODE_CUSTOM (0, 0, STACK_USE_NONE), + DECODE_END + }; + + return probes_decode_insn(insn, asi, table, false, false, stack_check_actions, NULL); +} + +const struct decode_checker t32_stack_checker[NUM_PROBES_T32_ACTIONS] = { + [PROBES_T32_LDMSTM] = {.checker = t32_check_stack}, + [PROBES_T32_LDRDSTRD] = {.checker = t32_check_stack}, + [PROBES_T32_LDRSTR] = {.checker = t32_check_stack}, +}; + +/* + * See following comments. This insn must be 'push'. + */ +static enum probes_insn __kprobes t16_check_stack(probes_opcode_t insn, + struct arch_probes_insn *asi, + const struct decode_header *h) +{ + unsigned int reglist = insn & 0x1ff; + asi->stack_space = hweight32(reglist) * 4; + return INSN_GOOD; +} + +/* + * T16 encoding is simple: only the 'push' insn can need extra stack space. + * Other insns, like str, can only use r0-r7 as Rn. + */ +const struct decode_checker t16_stack_checker[NUM_PROBES_T16_ACTIONS] = { + [PROBES_T16_PUSH] = {.checker = t16_check_stack}, +}; diff --git a/arch/arm/probes/kprobes/checkers.h b/arch/arm/probes/kprobes/checkers.h new file mode 100644 index 000000000000..bddfa0e82389 --- /dev/null +++ b/arch/arm/probes/kprobes/checkers.h @@ -0,0 +1,54 @@ +/* + * arch/arm/probes/kprobes/checkers.h + * + * Copyright (C) 2014 Huawei Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ +#ifndef _ARM_KERNEL_PROBES_CHECKERS_H +#define _ARM_KERNEL_PROBES_CHECKERS_H + +#include <linux/kernel.h> +#include <linux/types.h> +#include "../decode.h" + +extern probes_check_t checker_stack_use_none; +extern probes_check_t checker_stack_use_unknown; +#ifdef CONFIG_THUMB2_KERNEL +extern probes_check_t checker_stack_use_imm_0xx; +#else +extern probes_check_t checker_stack_use_imm_x0x; +#endif +extern probes_check_t checker_stack_use_imm_xxx; +extern probes_check_t checker_stack_use_stmdx; + +enum { + STACK_USE_NONE, + STACK_USE_UNKNOWN, +#ifdef CONFIG_THUMB2_KERNEL + STACK_USE_FIXED_0XX, + STACK_USE_T32STRD, +#else + STACK_USE_FIXED_X0X, +#endif + STACK_USE_FIXED_XXX, + STACK_USE_STMDX, + NUM_STACK_USE_TYPES +}; + +extern const union decode_action stack_check_actions[]; + +#ifndef CONFIG_THUMB2_KERNEL +extern const struct decode_checker arm_stack_checker[]; +#else +#endif +extern const struct decode_checker t32_stack_checker[]; +extern const struct decode_checker t16_stack_checker[]; +#endif |
