/* * arch/arm/kernel/kprobes-thumb.c * * Copyright (C) 2011 Jon Medhurst . * * 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. */ #include #include #include "kprobes.h" /* * True if current instruction is in an IT block. */ #define in_it_block(cpsr) ((cpsr & 0x06000c00) != 0x00000000) /* * Return the condition code to check for the currently executing instruction. * This is in ITSTATE<7:4> which is in CPSR<15:12> but is only valid if * in_it_block returns true. */ #define current_cond(cpsr) ((cpsr >> 12) & 0xf) /* * Return the PC value for a probe in thumb code. * This is the address of the probed instruction plus 4. * We subtract one because the address will have bit zero set to indicate * a pointer to thumb code. */ static inline unsigned long __kprobes thumb_probe_pc(struct kprobe *p) { return (unsigned long)p->addr - 1 + 4; } static void __kprobes t32_simulate_table_branch(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long pc = thumb_probe_pc(p); int rn = (insn >> 16) & 0xf; int rm = insn & 0xf; unsigned long rnv = (rn == 15) ? pc : regs->uregs[rn]; unsigned long rmv = regs->uregs[rm]; unsigned int halfwords; if (insn & 0x10) /* TBH */ halfwords = ((u16 *)rnv)[rmv]; else /* TBB */ halfwords = ((u8 *)rnv)[rmv]; regs->ARM_pc = pc + 2 * halfwords; } static void __kprobes t32_simulate_mrs(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; int rd = (insn >> 8) & 0xf; unsigned long mask = 0xf8ff03df; /* Mask out execution state */ regs->uregs[rd] = regs->ARM_cpsr & mask; } static void __kprobes t32_simulate_cond_branch(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long pc = thumb_probe_pc(p); long offset = insn & 0x7ff; /* imm11 */ offset += (insn & 0x003f0000) >> 5; /* imm6 */ offset += (insn & 0x00002000) << 4; /* J1 */ offset += (insn & 0x00000800) << 7; /* J2 */ offset -= (insn & 0x04000000) >> 7; /* Apply sign bit */ regs->ARM_pc = pc + (offset * 2); } static enum kprobe_insn __kprobes t32_decode_cond_branch(kprobe_opcode_t insn, struct arch_specific_insn *asi) { int cc = (insn >> 22) & 0xf; asi->insn_check_cc = kprobe_condition_checks[cc]; asi->insn_handler = t32_simulate_cond_branch; return INSN_GOOD_NO_SLOT; } static void __kprobes t32_simulate_branch(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long pc = thumb_probe_pc(p); long offset = insn & 0x7ff; /* imm11 */ offset += (insn & 0x03ff0000) >> 5; /* imm10 */ offset += (insn & 0x00002000) << 9; /* J1 */ offset += (insn & 0x00000800) << 10; /* J2 */ if (insn & 0x04000000) offset -= 0x00800000; /* Apply sign bit */ else offset ^= 0x00600000; /* Invert J1 and J2 */ if (insn & (1 << 14)) { /* BL or BLX */ regs->ARM_lr = (unsigned long)p->addr + 4; if (!(insn & (1 << 12))) { /* BLX so switch to ARM mode */ regs->ARM_cpsr &= ~PSR_T_BIT; pc &= ~3; } } regs->ARM_pc = pc + (offset * 2); } static void __kprobes t32_simulate_ldr_literal(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long addr = thumb_probe_pc(p) & ~3; int rt = (insn >> 12) & 0xf; unsigned long rtv; long offset = insn & 0xfff; if (insn & 0x00800000) addr += offset; else addr -= offset; if (insn & 0x00400000) { /* LDR */ rtv = *(unsigned long *)addr; if (rt == 15) { bx_write_pc(rtv, regs); return; } } else if (insn & 0x00200000) { /* LDRH */ if (insn & 0x01000000) rtv = *(s16 *)addr; else rtv = *(u16 *)addr; } else { /* LDRB */ if (insn & 0x01000000) rtv = *(s8 *)addr; else rtv = *(u8 *)addr; } regs->uregs[rt] = rtv; } static enum kprobe_insn __kprobes t32_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi) { enum kprobe_insn ret = kprobe_decode_ldmstm(insn, asi); /* Fixup modified instruction to have halfwords in correct order...*/ insn = asi->insn[0]; ((u16 *)asi->insn)[0] = insn >> 16; ((u16 *)asi->insn)[1] = insn & 0xffff; return ret; } static void __kprobes t32_emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long pc = thumb_probe_pc(p) & ~3; int rt1 = (insn >> 12) & 0xf; int rt2 = (insn >> 8) & 0xf; int rn = (insn >> 16) & 0xf; register unsigned long rt1v asm("r0") = regs->uregs[rt1]; register unsigned long rt2v asm("r1") = regs->uregs[rt2]; register unsigned long rnv asm("r2") = (rn == 15) ? pc : regs->uregs[rn]; __asm__ __volatile__ ( "blx %[fn]" : "=r" (rt1v), "=r" (rt2v), "=r" (rnv) : "0" (rt1v), "1" (rt2v), "2" (rnv), [fn] "r" (p->ainsn.insn_fn) : "lr", "memory", "cc" ); if (rn != 15) regs->uregs[rn] = rnv; /* Writeback base register */ regs->uregs[rt1] = rt1v; regs->uregs[rt2] = rt2v; } static void __kprobes t32_emulate_ldrstr(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; int rt = (insn >> 12) & 0xf; int rn = (insn >> 16) & 0xf; int rm = insn & 0xf; register unsigned long rtv asm("r0") = regs->uregs[rt]; register unsigned long rnv asm("r2") = regs->uregs[rn]; register unsigned long rmv asm("r3") = regs->uregs[rm]; __asm__ __volatile__ ( "blx %[fn]" : "=r" (rtv), "=r" (rnv) : "0" (rtv), "1" (rnv), "r" (rmv), [fn] "r" (p->ainsn.insn_fn) : "lr", "memory", "cc" ); regs->uregs[rn] = rnv; /* Writeback base register */ if (rt == 15) /* Can't be true for a STR as they aren't allowed */ bx_write_pc(rtv, regs); else regs->uregs[rt] = rtv; } static void __kprobes t32_emulate_rd8rn16rm0_rwflags(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; int rd = (insn >> 8) & 0xf; int rn = (insn >> 16) & 0xf; int rm = insn & 0xf; register unsigned long rdv asm("r1") = regs->uregs[rd]; register unsigned long rnv asm("r2") = regs->uregs[rn]; register unsigned long rmv asm("r3") = regs->uregs[rm]; unsigned long cpsr = regs->ARM_cpsr; __asm__ __volatile__ ( "msr cpsr_fs, %[cpsr] \n\t" "blx %[fn] \n\t" "mrs %[cpsr], cpsr \n\t" : "=r" (rdv), [cpsr] "=r" (cpsr) : "0" (rdv), "r" (rnv), "r" (rmv), "1" (cpsr), [fn] "r" (p->ainsn.insn_fn) : "lr", "memory", "cc" ); regs->uregs[rd] = rdv; regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK); } static void __kprobes t32_emulate_rd8pc16_noflags(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long pc = thumb_probe_pc(p); int rd = (insn >> 8) & 0xf; register unsigned long rdv asm("r1") = regs->uregs[rd]; register unsigned long rnv asm("r2") = pc & ~3; __asm__ __volatile__ ( "blx %[fn]" : "=r" (rdv) : "0" (rdv), "r" (rnv), [fn] "r" (p->ainsn.insn_fn) : "lr", "memory", "cc" ); regs->uregs[rd] = rdv; } static void __kprobes t32_emulate_rd8rn16_noflags(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; int rd = (insn >> 8) & 0xf; int rn = (insn >> 16) & 0xf; register unsigned long rdv asm("r1") = regs->uregs[rd]; register unsigned long rnv asm("r2") = regs->uregs[rn]; __asm__ __volatile__ ( "blx %[fn]" : "=r" (rdv) : "0" (rdv), "r" (rnv), [fn] "r" (p->ainsn.insn_fn) : "lr", "memory", "cc" ); regs->uregs[rd] = rdv; } static void __kprobes t32_emulate_rdlo12rdhi8rn16rm0_noflags(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; int rdlo = (insn >> 12) & 0xf; int rdhi = (insn >> 8) & 0xf; int rn = (insn >> 16) & 0xf; int rm = insn & 0xf; register unsigned long rdlov asm("r0") = regs->uregs[rdlo]; register unsigned long rdhiv asm("r1") = regs->uregs[rdhi]; register unsigned long rnv asm("r2") = regs->uregs[rn]; register unsigned long rmv asm("r3") = regs->uregs[rm]; __asm__ __volatile__ ( "blx %[fn]" : "=r" (rdlov), "=r" (rdhiv) : "0" (rdlov), "1" (rdhiv), "r" (rnv), "r" (rmv), [fn] "r" (p->ainsn.insn_fn) : "lr", "memory", "cc" ); regs->uregs[rdlo] = rdlov; regs->uregs[rdhi] = rdhiv; } static const union decode_item t32_table_1110_100x_x0xx[] = { /* Load/store multiple instructions */ /* Rn is PC 1110 100x x0xx 1111 xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xfe4f0000, 0xe80f0000), /* SRS 1110 1000 00x0 xxxx xxxx xxxx xxxx xxxx */ /* RFE 1110 1000 00x1 xxxx xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xffc00000, 0xe8000000), /* SRS 1110 1001 10x0 xxxx xxxx xxxx xxxx xxxx */ /* RFE 1110 1001 10x1 xxxx xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xffc00000, 0xe9800000), /* STM Rn, {...pc} 1110 100x x0x0 xxxx 1xxx xxxx xxxx xxxx */ DECODE_REJECT (0xfe508000, 0xe8008000), /* LDM Rn, {...lr,pc} 1110 100x x0x1 xxxx 11xx xxxx xxxx xxxx */ DECODE_REJECT (0xfe50c000, 0xe810c000), /* LDM/STM Rn, {...sp} 1110 100x x0xx xxxx xx1x xxxx xxxx xxxx */ DECODE_REJECT (0xfe402000, 0xe8002000), /* STMIA 1110 1000 10x0 xxxx xxxx xxxx xxxx xxxx */ /* LDMIA 1110 1000 10x1 xxxx xxxx xxxx xxxx xxxx */ /* STMDB 1110 1001 00x0 xxxx xxxx xxxx xxxx xxxx */ /* LDMDB 1110 1001 00x1 xxxx xxxx xxxx xxxx xxxx */ DECODE_CUSTOM (0xfe400000, 0xe8000000, t32_decode_ldmstm), DECODE_END }; static const union decode_item t32_table_1110_100x_x1xx[] = { /* Load/store dual, load/store exclusive, table branch */ /* STRD (immediate) 1110 1000 x110 xxxx xxxx xxxx xxxx xxxx */ /* LDRD (immediate) 1110 1000 x111 xxxx xxxx xxxx xxxx xxxx */ DECODE_OR (0xff600000, 0xe8600000), /* STRD (immediate) 1110 1001 x1x0 xxxx xxxx xxxx xxxx xxxx */ /* LDRD (immediate) 1110 1001 x1x1 xxxx xxxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xff400000, 0xe9400000, t32_emulate_ldrdstrd, REGS(NOPCWB, NOSPPC, NOSPPC, 0, 0)), /* TBB 1110 1000 1101 xxxx xxxx xxxx 0000 xxxx */ /* TBH 1110 1000 1101 xxxx xxxx xxxx 0001 xxxx */ DECODE_SIMULATEX(0xfff000e0, 0xe8d00000, t32_simulate_table_branch, REGS(NOSP, 0, 0, 0, NOSPPC)), /* STREX 1110 1000 0100 xxxx xxxx xxxx xxxx xxxx */ /* LDREX 1110 1000 0101 xxxx xxxx xxxx xxxx xxxx */ /* STREXB 1110 1000 1100 xxxx xxxx xxxx 0100 xxxx */ /* STREXH 1110 1000 1100 xxxx xxxx xxxx 0101 xxxx */ /* STREXD 1110 1000 1100 xxxx xxxx xxxx 0111 xxxx */ /* LDREXB 1110 1000 1101 xxxx xxxx xxxx 0100 xxxx */ /* LDREXH 1110 1000 1101 xxxx xxxx xxxx 0101 xxxx */ /* LDREXD 1110 1000 1101 xxxx xxxx xxxx 0111 xxxx */ /* And unallocated instructions... */ DECODE_END }; static const union decode_item t32_table_1110_101x[] = { /* Data-processing (shifted register) */ /* TST 1110 1010 0001 xxxx xxxx 1111 xxxx xxxx */ /* TEQ 1110 1010 1001 xxxx xxxx 1111 xxxx xxxx */ DECODE_EMULATEX (0xff700f00, 0xea100f00, t32_emulate_rd8rn16rm0_rwflags, REGS(NOSPPC, 0, 0, 0, NOSPPC)), /* CMN 1110 1011 0001 xxxx xxxx 1111 xxxx xxxx */ DECODE_OR (0xfff00f00, 0xeb100f00), /* CMP 1110 1011 1011 xxxx xxxx 1111 xxxx xxxx */ DECODE_EMULATEX (0xfff00f00, 0xebb00f00, t32_emulate_rd8rn16rm0_rwflags, REGS(NOPC, 0, 0, 0, NOSPPC)), /* MOV 1110 1010 010x 1111 xxxx xxxx xxxx xxxx */ /* MVN 1110 1010 011x 1111 xxxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xffcf0000, 0xea4f0000, t32_emulate_rd8rn16rm0_rwflags, REGS(0, 0, NOSPPC, 0, NOSPPC)), /* ??? 1110 1010 101x xxxx xxxx xxxx xxxx xxxx */ /* ??? 1110 1010 111x xxxx xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xffa00000, 0xeaa00000), /* ??? 1110 1011 001x xxxx xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xffe00000, 0xeb200000), /* ??? 1110 1011 100x xxxx xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xffe00000, 0xeb800000), /* ??? 1110 1011 111x xxxx xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xffe00000, 0xebe00000), /* ADD/SUB SP, SP, Rm, LSL #0..3 */ /* 1110 1011 x0xx 1101 x000 1101 xx00 xxxx */ DECODE_EMULATEX (0xff4f7f30, 0xeb0d0d00, t32_emulate_rd8rn16rm0_rwflags, REGS(SP, 0, SP, 0, NOSPPC)), /* ADD/SUB SP, SP, Rm, shift */ /* 1110 1011 x0xx 1101 xxxx 1101 xxxx xxxx */ DECODE_REJECT (0xff4f0f00, 0xeb0d0d00), /* ADD/SUB Rd, SP, Rm, shift */ /* 1110 1011 x0xx 1101 xxxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xff4f0000, 0xeb0d0000, t32_emulate_rd8rn16rm0_rwflags, REGS(SP, 0, NOPC, 0, NOSPPC)), /* AND 1110 1010 000x xxxx xxxx xxxx xxxx xxxx */ /* BIC 1110 1010 001x xxxx xxxx xxxx xxxx xxxx */ /* ORR 1110 1010 010x xxxx xxxx xxxx xxxx xxxx */ /* ORN 1110 1010 011x xxxx xxxx xxxx xxxx xxxx */ /* EOR 1110 1010 100x xxxx xxxx xxxx xxxx xxxx */ /* PKH 1110 1010 110x xxxx xxxx xxxx xxxx xxxx */ /* ADD 1110 1011 000x xxxx xxxx xxxx xxxx xxxx */ /* ADC 1110 1011 010x xxxx xxxx xxxx xxxx xxxx */ /* SBC 1110 1011 011x xxxx xxxx xxxx xxxx xxxx */ /* SUB 1110 1011 101x xxxx xxxx xxxx xxxx xxxx */ /* RSB 1110 1011 110x xxxx xxxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfe000000, 0xea000000, t32_emulate_rd8rn16rm0_rwflags, REGS(NOSPPC, 0, NOSPPC, 0, NOSPPC)), DECODE_END }; static const union decode_item t32_table_1111_0x0x___0[] = { /* Data-processing (modified immediate) */ /* TST 1111 0x00 0001 xxxx 0xxx 1111 xxxx xxxx */ /* TEQ 1111 0x00 1001 xxxx 0xxx 1111 xxxx xxxx */ DECODE_EMULATEX (0xfb708f00, 0xf0100f00, t32_emulate_rd8rn16rm0_rwflags, REGS(NOSPPC, 0, 0, 0, 0)), /* CMN 1111 0x01 0001 xxxx 0xxx 1111 xxxx xxxx */ DECODE_OR (0xfbf08f00, 0xf1100f00), /* CMP 1111 0x01 1011 xxxx 0xxx 1111 xxxx xxxx */ DECODE_EMULATEX (0xfbf08f00, 0xf1b00f00, t32_emulate_rd8rn16rm0_rwflags, REGS(NOPC, 0, 0, 0, 0)), /* MOV 1111 0x00 010x 1111 0xxx xxxx xxxx xxxx */ /* MVN 1111 0x00 011x 1111 0xxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfbcf8000, 0xf04f0000, t32_emulate_rd8rn16rm0_rwflags, REGS(0, 0, NOSPPC, 0, 0)), /* ??? 1111 0x00 101x xxxx 0xxx xxxx xxxx xxxx */ DECODE_REJECT (0xfbe08000, 0xf0a00000), /* ??? 1111 0x00 110x xxxx 0xxx xxxx xxxx xxxx */ /* ??? 1111 0x00 111x xxxx 0xxx xxxx xxxx xxxx */ DECODE_REJECT (0xfbc08000, 0xf0c00000), /* ??? 1111 0x01 001x xxxx 0xxx xxxx xxxx xxxx */ DECODE_REJECT (0xfbe08000, 0xf1200000), /* ??? 1111 0x01 100x xxxx 0xxx xxxx xxxx xxxx */ DECODE_REJECT (0xfbe08000, 0xf1800000), /* ??? 1111 0x01 111x xxxx 0xxx xxxx xxxx xxxx */ DECODE_REJECT (0xfbe08000, 0xf1e00000), /* ADD Rd, SP, #imm 1111 0x01 000x 1101 0xxx xxxx xxxx xxxx */ /* SUB Rd, SP, #imm 1111 0x01 101x 1101 0xxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfb4f8000, 0xf10d0000, t32_emulate_rd8rn16rm0_rwflags, REGS(SP, 0, NOPC, 0, 0)), /* AND 1111 0x00 000x xxxx 0xxx xxxx xxxx xxxx */ /* BIC 1111 0x00 001x xxxx 0xxx xxxx xxxx xxxx */ /* ORR 1111 0x00 010x xxxx 0xxx xxxx xxxx xxxx */ /* ORN 1111 0x00 011x xxxx 0xxx xxxx xxxx xxxx */ /* EOR 1111 0x00 100x xxxx 0xxx xxxx xxxx xxxx */ /* ADD 1111 0x01 000x xxxx 0xxx xxxx xxxx xxxx */ /* ADC 1111 0x01 010x xxxx 0xxx xxxx xxxx xxxx */ /* SBC 1111 0x01 011x xxxx 0xxx xxxx xxxx xxxx */ /* SUB 1111 0x01 101x xxxx 0xxx xxxx xxxx xxxx */ /* RSB 1111 0x01 110x xxxx 0xxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfa008000, 0xf0000000, t32_emulate_rd8rn16rm0_rwflags, REGS(NOSPPC, 0, NOSPPC, 0, 0)), DECODE_END }; static const union decode_item t32_table_1111_0x1x___0[] = { /* Data-processing (plain binary immediate) */ /* ADDW Rd, PC, #imm 1111 0x10 0000 1111 0xxx xxxx xxxx xxxx */ DECODE_OR (0xfbff8000, 0xf20f0000), /* SUBW Rd, PC, #imm 1111 0x10 1010 1111 0xxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfbff8000, 0xf2af0000, t32_emulate_rd8pc16_noflags, REGS(PC, 0, NOSPPC, 0, 0)), /* ADDW SP, SP, #imm 1111 0x10 0000 1101 0xxx 1101 xxxx xxxx */ DECODE_OR (0xfbff8f00, 0xf20d0d00), /* SUBW SP, SP, #imm 1111 0x10 1010 1101 0xxx 1101 xxxx xxxx */ DECODE_EMULATEX (0xfbff8f00, 0xf2ad0d00, t32_emulate_rd8rn16_noflags, REGS(SP, 0, SP, 0, 0)), /* ADDW 1111 0x10 0000 xxxx 0xxx xxxx xxxx xxxx */ DECODE_OR (0xfbf08000, 0xf2000000), /* SUBW 1111 0x10 1010 xxxx 0xxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfbf08000, 0xf2a00000, t32_emulate_rd8rn16_noflags, REGS(NOPCX, 0, NOSPPC, 0, 0)), /* MOVW 1111 0x10 0100 xxxx 0xxx xxxx xxxx xxxx */ /* MOVT 1111 0x10 1100 xxxx 0xxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfb708000, 0xf2400000, t32_emulate_rd8rn16_noflags, REGS(0, 0, NOSPPC, 0, 0)), /* SSAT16 1111 0x11 0010 xxxx 0000 xxxx 00xx xxxx */ /* SSAT 1111 0x11 00x0 xxxx 0xxx xxxx xxxx xxxx */ /* USAT16 1111 0x11 1010 xxxx 0000 xxxx 00xx xxxx */ /* USAT 1111 0x11 10x0 xxxx 0xxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfb508000, 0xf3000000, t32_emulate_rd8rn16rm0_rwflags, REGS(NOSPPC, 0, NOSPPC, 0, 0)), /* SFBX 1111 0x11 0100 xxxx 0xxx xxxx xxxx xxxx */ /* UFBX 1111 0x11 1100 xxxx 0xxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfb708000, 0xf3400000, t32_emulate_rd8rn16_noflags, REGS(NOSPPC, 0, NOSPPC, 0, 0)), /* BFC 1111 0x11 0110 1111 0xxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfbff8000, 0xf36f0000, t32_emulate_rd8rn16_noflags, REGS(0, 0, NOSPPC, 0, 0)), /* BFI 1111 0x11 0110 xxxx 0xxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfbf08000, 0xf3600000, t32_emulate_rd8rn16_noflags, REGS(NOSPPCX, 0, NOSPPC, 0, 0)), DECODE_END }; static const union decode_item t32_table_1111_0xxx___1[] = { /* Branches and miscellaneous control */ /* YIELD 1111 0011 1010 xxxx 10x0 x000 0000 0001 */ DECODE_OR (0xfff0d7ff, 0xf3a08001), /* SEV 1111 0011 1010 xxxx 10x0 x000 0000 0100 */ DECODE_EMULATE (0xfff0d7ff, 0xf3a08004, kprobe_emulate_none), /* NOP 1111 0011 1010 xxxx 10x0 x000 0000 0000 */ /* WFE 1111 0011 1010 xxxx 10x0 x000 0000 0010 */ /* WFI 1111 0011 1010 xxxx 10x0 x000 0000 0011 */ DECODE_SIMULATE (0xfff0d7fc, 0xf3a08000, kprobe_simulate_nop), /* MRS Rd, CPSR 1111 0011 1110 xxxx 10x0 xxxx xxxx xxxx */ DECODE_SIMULATEX(0xfff0d000, 0xf3e08000, t32_simulate_mrs, REGS(0, 0, NOSPPC, 0, 0)), /* * Unsupported instructions * 1111 0x11 1xxx xxxx 10x0 xxxx xxxx xxxx * * MSR 1111 0011 100x xxxx 10x0 xxxx xxxx xxxx * DBG hint 1111 0011 1010 xxxx 10x0 x000 1111 xxxx * Unallocated hints 1111 0011 1010 xxxx 10x0 x000 xxxx xxxx * CPS 1111 0011 1010 xxxx 10x0 xxxx xxxx xxxx * CLREX/DSB/DMB/ISB 1111 0011 1011 xxxx 10x0 xxxx xxxx xxxx * BXJ 1111 0011 1100 xxxx 10x0 xxxx xxxx xxxx * SUBS PC,LR,# 1111 0011 1101 xxxx 10x0 xxxx xxxx xxxx * MRS Rd, SPSR 1111 0011 1111 xxxx 10x0 xxxx xxxx xxxx * SMC 1111 0111 1111 xxxx 1000 xxxx xxxx xxxx * UNDEFINED 1111 0111 1111 xxxx 1010 xxxx xxxx xxxx * ??? 1111 0111 1xxx xxxx 1010 xxxx xxxx xxxx */ DECODE_REJECT (0xfb80d000, 0xf3808000), /* Bcc 1111 0xxx xxxx xxxx 10x0 xxxx xxxx xxxx */ DECODE_CUSTOM (0xf800d000, 0xf0008000, t32_decode_cond_branch), /* BLX 1111 0xxx xxxx xxxx 11x0 xxxx xxxx xxx0 */ DECODE_OR (0xf800d001, 0xf000c000), /* B 1111 0xxx xxxx xxxx 10x1 xxxx xxxx xxxx */ /* BL 1111 0xxx xxxx xxxx 11x1 xxxx xxxx xxxx */ DECODE_SIMULATE (0xf8009000, 0xf0009000, t32_simulate_branch), DECODE_END }; static const union decode_item t32_table_1111_100x_x0x1__1111[] = { /* Memory hints */ /* PLD (literal) 1111 1000 x001 1111 1111 xxxx xxxx xxxx */ /* PLI (literal) 1111 1001 x001 1111 1111 xxxx xxxx xxxx */ DECODE_SIMULATE (0xfe7ff000, 0xf81ff000, kprobe_simulate_nop), /* PLD{W} (immediate) 1111 1000 10x1 xxxx 1111 xxxx xxxx xxxx */ DECODE_OR (0xffd0f000, 0xf890f000), /* PLD{W} (immediate) 1111 1000 00x1 xxxx 1111 1100 xxxx xxxx */ DECODE_OR (0xffd0ff00, 0xf810fc00), /* PLI (immediate) 1111 1001 1001 xxxx 1111 xxxx xxxx xxxx */ DECODE_OR (0xfff0f000, 0xf990f000), /* PLI (immediate) 1111 1001 0001 xxxx 1111 1100 xxxx xxxx */ DECODE_SIMULATEX(0xfff0ff00, 0xf910fc00, kprobe_simulate_nop, REGS(NOPCX, 0, 0, 0, 0)), /* PLD{W} (register) 1111 1000 00x1 xxxx 1111 0000 00xx xxxx */ DECODE_OR (0xffd0ffc0, 0xf810f000), /* PLI (register) 1111 1001 0001 xxxx 1111 0000 00xx xxxx */ DECODE_SIMULATEX(0xfff0ffc0, 0xf910f000, kprobe_simulate_nop, REGS(NOPCX, 0, 0, 0, NOSPPC)), /* Other unallocated instructions... */ DECODE_END }; static const union decode_item t32_table_1111_100x[] = { /* Store/Load single data item */ /* ??? 1111 100x x11x xxxx xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xfe600000, 0xf8600000), /* ??? 1111 1001 0101 xxxx xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xfff00000, 0xf9500000), /* ??? 1111 100x 0xxx xxxx xxxx 10x0 xxxx xxxx */ DECODE_REJECT (0xfe800d00, 0xf8000800), /* STRBT 1111 1000 0000 xxxx xxxx 1110 xxxx xxxx */ /* STRHT 1111 1000 0010 xxxx xxxx 1110 xxxx xxxx */ /* STRT 1111 1000 0100 xxxx xxxx 1110 xxxx xxxx */ /* LDRBT 1111 1000 0001 xxxx xxxx 1110 xxxx xxxx */ /* LDRSBT 1111 1001 0001 xxxx xxxx 1110 xxxx xxxx */ /* LDRHT 1111 1000 0011 xxxx xxxx 1110 xxxx xxxx */ /* LDRSHT 1111 1001 0011 xxxx xxxx 1110 xxxx xxxx */ /* LDRT 1111 1000 0101 xxxx xxxx 1110 xxxx xxxx */ DECODE_REJECT (0xfe800f00, 0xf8000e00), /* STR{,B,H} Rn,[PC...] 1111 1000 xxx0 1111 xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xff1f0000, 0xf80f0000), /* STR{,B,H} PC,[Rn...] 1111 1000 xxx0 xxxx 1111 xxxx xxxx xxxx */ DECODE_REJECT (0xff10f000, 0xf800f000), /* LDR (literal) 1111 1000 x101 1111 xxxx xxxx xxxx xxxx */ DECODE_SIMULATEX(0xff7f0000, 0xf85f0000, t32_simulate_ldr_literal, REGS(PC, ANY, 0, 0, 0)), /* STR (immediate) 1111 1000 0100 xxxx xxxx 1xxx xxxx xxxx */ /* LDR (immediate) 1111 1000 0101 xxxx xxxx 1xxx xxxx xxxx */ DECODE_OR (0xffe00800, 0xf8400800), /* STR (immediate) 1111 1000 1100 xxxx xxxx xxxx xxxx xxxx */ /* LDR (immediate) 1111 1000 1101 xxxx xxxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xffe00000, 0xf8c00000, t32_emulate_ldrstr, REGS(NOPCX, ANY, 0, 0, 0)), /* STR (register) 1111 1000 0100 xxxx xxxx 0000 00xx xxxx */ /* LDR (register) 1111 1000 0101 xxxx xxxx 0000 00xx xxxx */ DECODE_EMULATEX (0xffe00fc0, 0xf8400000, t32_emulate_ldrstr, REGS(NOPCX, ANY, 0, 0, NOSPPC)), /* LDRB (literal) 1111 1000 x001 1111 xxxx xxxx xxxx xxxx */ /* LDRSB (literal) 1111 1001 x001 1111 xxxx xxxx xxxx xxxx */ /* LDRH (literal) 1111 1000 x011 1111 xxxx xxxx xxxx xxxx */ /* LDRSH (literal) 1111 1001 x011 1111 xxxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfe5f0000, 0xf81f0000, t32_simulate_ldr_literal, REGS(PC, NOSPPCX, 0, 0, 0)), /* STRB (immediate) 1111 1000 0000 xxxx xxxx 1xxx xxxx xxxx */ /* STRH (immediate) 1111 1000 0010 xxxx xxxx 1xxx xxxx xxxx */ /* LDRB (immediate) 1111 1000 0001 xxxx xxxx 1xxx xxxx xxxx */ /* LDRSB (immediate) 1111 1001 0001 xxxx xxxx 1xxx xxxx xxxx */ /* LDRH (immediate) 1111 1000 0011 xxxx xxxx 1xxx xxxx xxxx */ /* LDRSH (immediate) 1111 1001 0011 xxxx xxxx 1xxx xxxx xxxx */ DECODE_OR (0xfec00800, 0xf8000800), /* STRB (immediate) 1111 1000 1000 xxxx xxxx xxxx xxxx xxxx */ /* STRH (immediate) 1111 1000 1010 xxxx xxxx xxxx xxxx xxxx */ /* LDRB (immediate) 1111 1000 1001 xxxx xxxx xxxx xxxx xxxx */ /* LDRSB (immediate) 1111 1001 1001 xxxx xxxx xxxx xxxx xxxx */ /* LDRH (immediate) 1111 1000 1011 xxxx xxxx xxxx xxxx xxxx */ /* LDRSH (immediate) 1111 1001 1011 xxxx xxxx xxxx xxxx xxxx */ DECODE_EMULATEX (0xfec00000, 0xf8800000, t32_emulate_ldrstr, REGS(NOPCX, NOSPPCX, 0, 0, 0)), /* STRB (register) 1111 1000 0000 xxxx xxxx 0000 00xx xxxx */ /* STRH (register) 1111 1000 0010 xxxx xxxx 0000 00xx xxxx */ /* LDRB (register) 1111 1000 0001 xxxx xxxx 0000 00xx xxxx */ /* LDRSB (register) 1111 1001 0001 xxxx xxxx 0000 00xx xxxx */ /* LDRH (register) 1111 1000 0011 xxxx xxxx 0000 00xx xxxx */ /* LDRSH (register) 1111 1001 0011 xxxx xxxx 0000 00xx xxxx */ DECODE_EMULATEX (0xfe800fc0, 0xf8000000, t32_emulate_ldrstr, REGS(NOPCX, NOSPPCX, 0, 0, NOSPPC)), /* Other unallocated instructions... */ DECODE_END }; static const union decode_item t32_table_1111_1010___1111[] = { /* Data-processing (register) */ /* ??? 1111 1010 011x xxxx 1111 xxxx 1xxx xxxx */ DECODE_REJECT (0xffe0f080, 0xfa60f080), /* SXTH 1111 1010 0000 1111 1111 xxxx 1xxx xxxx */ /* UXTH 1111 1010 0001 1111 1111 xxxx 1xxx xxxx */ /* SXTB16 1111 1010 0010 1111 1111 xxxx 1xxx xxxx */ /* UXTB16 1111 1010 0011 1111 1111 xxxx 1xxx xxxx */ /* SXTB 1111 1010 0100 1111 1111 xxxx 1xxx xxxx */ /* UXTB 1111 1010 0101 1111 1111 xxxx 1xxx xxxx */ DECODE_EMULATEX (0xff8ff080, 0xfa0ff080, t32_emulate_rd8rn16rm0_rwflags, REGS(0, 0, NOSPPC, 0, NOSPPC)), /* ??? 1111 1010 1xxx xxxx 1111 xxxx 0x11 xxxx */ DECODE_REJECT (0xff80f0b0, 0xfa80f030), /* ??? 1111 1010 1x11 xxxx 1111 xxxx 0xxx xxxx */ DECODE_REJECT (0xffb0f080, 0xfab0f000), /* SADD16 1111 1010 1001 xxxx 1111 xxxx 0000 xxxx */ /* SASX 1111 1010 1010 xxxx 1111 xxxx 0000 xxxx */ /* SSAX 1111 1010 1110 xxxx 1111 xxxx 0000 xxxx */ /* SSUB16 1111 1010 1101 xxxx 1111 xxxx 0000 xxxx */ /* SADD8 1111 1010 1000 xxxx 1111 xxxx 0000 xxxx */ /* SSUB8 1111 1010 1100 xxxx 1111 xxxx 0000 xxxx */ /* QADD16 1111 1010 1001 xxxx 1111 xxxx 0001 xxxx */ /* QASX 1111 1010 1010 xxxx 1111 xxxx 0001 xxxx */ /* QSAX 1111 1010 1110 xxxx 1111 xxxx 0001 xxxx */ /* QSUB16 1111 1010 1101 xxxx 1111 xxxx 0001 xxxx */ /* QADD8 1111 1010 1000 xxxx 1111 xxxx 0001 xxxx */ /* QSUB8 1111 1010 1100 xxxx 1111 xxxx 0001 xxxx */ /* SHADD16 1111 1010 1001 xxxx 1111 xxxx 0010 xxxx */ /* SHASX 1111 1010 1010 xxxx 1111 xxxx 0010 xxxx */ /* SHSAX 1111 1010 1110 xxxx 1111 xxxx 0010 xxxx */ /* SHSUB16 1111 1010 1101 xxxx 1111 xxxx 0010 xxxx */ /* SHADD8 1111 1010 1000 xxxx 1111 xxxx 0010 xxxx */ /* SHSUB8 1111 1010 1100 xxxx 1111 xxxx 0010 xxxx */ /* UADD16 1111 1010 1001 xxxx 1111 xxxx 0100 xxxx */ /* UASX 1111 1010 1010 xxxx 1111 xxxx 0100 xxxx */ /* USAX 1111 1010 1110 xxxx 1111 xxxx 0100 xxxx */ /* USUB16 1111 1010 1101 xxxx 1111 xxxx 0100 xxxx */ /* UADD8 1111 1010 1000 xxxx 1111 xxxx 0100 xxxx */ /* USUB8 1111 1010 1100 xxxx 1111 xxxx 0100 xxxx */ /* UQADD16 1111 1010 1001 xxxx 1111 xxxx 0101 xxxx */ /* UQASX 1111 1010 1010 xxxx 1111 xxxx 0101 xxxx */ /* UQSAX 1111 1010 1110 xxxx 1111 xxxx 0101 xxxx */ /* UQSUB16 1111 1010 1101 xxxx 1111 xxxx 0101 xxxx */ /* UQADD8 1111 1010 1000 xxxx 1111 xxxx 0101 xxxx */ /* UQSUB8 1111 1010 1100 xxxx 1111 xxxx 0101 xxxx */ /* UHADD16 1111 1010 1001 xxxx 1111 xxxx 0110 xxxx */ /* UHASX 1111 1010 1010 xxxx 1111 xxxx 0110 xxxx */ /* UHSAX 1111 1010 1110 xxxx 1111 xxxx 0110 xxxx */ /* UHSUB16 1111 1010 1101 xxxx 1111 xxxx 0110 xxxx */ /* UHADD8 1111 1010 1000 xxxx 1111 xxxx 0110 xxxx */ /* UHSUB8 1111 1010 1100 xxxx 1111 xxxx 0110 xxxx */ DECODE_OR (0xff80f080, 0xfa80f000), /* SXTAH 1111 1010 0000 xxxx 1111 xxxx 1xxx xxxx */ /* UXTAH 1111 1010 0001 xxxx 1111 xxxx 1xxx xxxx */ /* SXTAB16 1111 1010 0010 xxxx 1111 xxxx 1xxx xxxx */ /* UXTAB16 1111 1010 0011 xxxx 1111 xxxx 1xxx xxxx */ /* SXTAB 1111 1010 0100 xxxx 1111 xxxx 1xxx xxxx */ /* UXTAB 1111 1010 0101 xxxx 1111 xxxx 1xxx xxxx */ DECODE_OR (0xff80f080, 0xfa00f080), /* QADD 1111 1010 1000 xxxx 1111 xxxx 1000 xxxx */ /* QDADD 1111 1010 1000 xxxx 1111 xxxx 1001 xxxx */ /* QSUB 1111 1010 1000 xxxx 1111 xxxx 1010 xxxx */ /* QDSUB 1111 1010 1000 xxxx 1111 xxxx 1011 xxxx */ DECODE_OR (0xfff0f0c0, 0xfa80f080), /* SEL 1111 1010 1010 xxxx 1111 xxxx 1000 xxxx */ DECODE_OR (0xfff0f0f0, 0xfaa0f080), /* LSL 1111 1010 000x xxxx 1111 xxxx 0000 xxxx */ /* LSR 1111 1010 001x xxxx 1111 xxxx 0000 xxxx */ /* ASR 1111 1010 010x xxxx 1111 xxxx 0000 xxxx */ /* ROR 1111 1010 011x xxxx 1111 xxxx 0000 xxxx */ DECODE_EMULATEX (0xff80f0f0, 0xfa00f000, t32_emulate_rd8rn16rm0_rwflags, REGS(NOSPPC, 0, NOSPPC, 0, NOSPPC)), /* CLZ 1111 1010 1010 xxxx 1111 xxxx 1000 xxxx */ DECODE_OR (0xfff0f0f0, 0xfab0f080), /* REV 1111 1010 1001 xxxx 1111 xxxx 1000 xxxx */ /* REV16 1111 1010 1001 xxxx 1111 xxxx 1001 xxxx */ /* RBIT 1111 1010 1001 xxxx 1111 xxxx 1010 xxxx */ /* REVSH 1111 1010 1001 xxxx 1111 xxxx 1011 xxxx */ DECODE_EMULATEX (0xfff0f0c0, 0xfa90f080, t32_emulate_rd8rn16_noflags, REGS(NOSPPC, 0, NOSPPC, 0, SAMEAS16)), /* Other unallocated instructions... */ DECODE_END }; static const union decode_item t32_table_1111_1011_1[] = { /* Long multiply, long multiply accumulate, and divide */ /* UMAAL 1111 1011 1110 xxxx xxxx xxxx 0110 xxxx */ DECODE_OR (0xfff000f0, 0xfbe00060), /* SMLALxy 1111 1011 1100 xxxx xxxx xxxx 10xx xxxx */ DECODE_OR (0xfff000c0, 0xfbc00080), /* SMLALD{X} 1111 1011 1100 xxxx xxxx xxxx 110x xxxx */ /* SMLSLD{X} 1111 1011 1101 xxxx xxxx xxxx 110x xxxx */ DECODE_OR (0xffe000e0, 0xfbc000c0), /* SMULL 1111 1011 1000 xxxx xxxx xxxx 0000 xxxx */ /* UMULL 1111 1011 1010 xxxx xxxx xxxx 0000 xxxx */ /* SMLAL 1111 1011 1100 xxxx xxxx xxxx 0000 xxxx */ /* UMLAL 1111 1011 1110 xxxx xxxx xxxx 0000 xxxx */ DECODE_EMULATEX (0xff9000f0, 0xfb800000, t32_emulate_rdlo12rdhi8rn16rm0_noflags, REGS(NOSPPC, NOSPPC, NOSPPC, 0, NOSPPC)), /* SDIV 1111 1011 1001 xxxx xxxx xxxx 1111 xxxx */ /* UDIV 1111 1011 1011 xxxx xxxx xxxx 1111 xxxx */ /* Other unallocated instructions... */ DECODE_END }; const union decode_item kprobe_decode_thumb32_table[] = { /* * Load/store multiple instructions * 1110 100x x0xx xxxx xxxx xxxx xxxx xxxx */ DECODE_TABLE (0xfe400000, 0xe8000000, t32_table_1110_100x_x0xx), /* * Load/store dual, load/store exclusive, table branch * 1110 100x x1xx xxxx xxxx xxxx xxxx xxxx */ DECODE_TABLE (0xfe400000, 0xe8400000, t32_table_1110_100x_x1xx), /* * Data-processing (shifted register) * 1110 101x xxxx xxxx xxxx xxxx xxxx xxxx */ DECODE_TABLE (0xfe000000, 0xea000000, t32_table_1110_101x), /* * Coprocessor instructions * 1110 11xx xxxx xxxx xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xfc000000, 0xec000000), /* * Data-processing (modified immediate) * 1111 0x0x xxxx xxxx 0xxx xxxx xxxx xxxx */ DECODE_TABLE (0xfa008000, 0xf0000000, t32_table_1111_0x0x___0), /* * Data-processing (plain binary immediate) * 1111 0x1x xxxx xxxx 0xxx xxxx xxxx xxxx */ DECODE_TABLE (0xfa008000, 0xf2000000, t32_table_1111_0x1x___0), /* * Branches and miscellaneous control * 1111 0xxx xxxx xxxx 1xxx xxxx xxxx xxxx */ DECODE_TABLE (0xf8008000, 0xf0008000, t32_table_1111_0xxx___1), /* * Advanced SIMD element or structure load/store instructions * 1111 1001 xxx0 xxxx xxxx xxxx xxxx xxxx */ DECODE_REJECT (0xff100000, 0xf9000000), /* * Memory hints * 1111 100x x0x1 xxxx 1111 xxxx xxxx xxxx */ DECODE_TABLE (0xfe50f000, 0xf810f000, t32_table_1111_100x_x0x1__1111), /* * Store single data item * 1111 1000 xxx0 xxxx xxxx xxxx xxxx xxxx * Load single data items * 1111 100x xxx1 xxxx xxxx xxxx xxxx xxxx */ DECODE_TABLE (0xfe000000, 0xf8000000, t32_table_1111_100x), /* * Data-processing (register) * 1111 1010 xxxx xxxx 1111 xxxx xxxx xxxx */ DECODE_TABLE (0xff00f000, 0xfa00f000, t32_table_1111_1010___1111), /* * Long multiply, long multiply accumulate, and divide * 1111 1011 1xxx xxxx xxxx xxxx xxxx xxxx */ DECODE_TABLE (0xff800000, 0xfb800000, t32_table_1111_1011_1), /* * Coprocessor instructions * 1111 11xx xxxx xxxx xxxx xxxx xxxx xxxx */ DECODE_END }; static void __kprobes t16_simulate_bxblx(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long pc = thumb_probe_pc(p); int rm = (insn >> 3) & 0xf; unsigned long rmv = (rm == 15) ? pc : regs->uregs[rm]; if (insn & (1 << 7)) /* BLX ? */ regs->ARM_lr = (unsigned long)p->addr + 2; bx_write_pc(rmv, regs); } static void __kprobes t16_simulate_ldr_literal(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long* base = (unsigned long *)(thumb_probe_pc(p) & ~3); long index = insn & 0xff; int rt = (insn >> 8) & 0x7; regs->uregs[rt] = base[index]; } static void __kprobes t16_simulate_ldrstr_sp_relative(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long* base = (unsigned long *)regs->ARM_sp; long index = insn & 0xff; int rt = (insn >> 8) & 0x7; if (insn & 0x800) /* LDR */ regs->uregs[rt] = base[index]; else /* STR */ base[index] = regs->uregs[rt]; } static void __kprobes t16_simulate_reladr(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long base = (insn & 0x800) ? regs->ARM_sp : (thumb_probe_pc(p) & ~3); long offset = insn & 0xff; int rt = (insn >> 8) & 0x7; regs->uregs[rt] = base + offset * 4; } static void __kprobes t16_simulate_add_sp_imm(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; long imm = insn & 0x7f; if (insn & 0x80) /* SUB */ regs->ARM_sp -= imm * 4; else /* ADD */ regs->ARM_sp += imm * 4; } static void __kprobes t16_simulate_cbz(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; int rn = insn & 0x7; kprobe_opcode_t nonzero = regs->uregs[rn] ? insn : ~insn; if (nonzero & 0x800) { long i = insn & 0x200; long imm5 = insn & 0xf8; unsigned long pc = thumb_probe_pc(p); regs->ARM_pc = pc + (i >> 3) + (imm5 >> 2); } } static void __kprobes t16_simulate_it(struct kprobe *p, struct pt_regs *regs) { /* * The 8 IT state bits are split into two parts in CPSR: * ITSTATE<1:0> are in CPSR<26:25> * ITSTATE<7:2> are in CPSR<15:10> * The new IT state is in the lower byte of insn. */ kprobe_opcode_t insn = p->opcode; unsigned long cpsr = regs->ARM_cpsr; cpsr &= ~PSR_IT_MASK; cpsr |= (insn & 0xfc) << 8; cpsr |= (insn & 0x03) << 25; regs->ARM_cpsr = cpsr; } static void __kprobes t16_singlestep_it(struct kprobe *p, struct pt_regs *regs) { regs->ARM_pc += 2; t16_simulate_it(p, regs); } static enum kprobe_insn __kprobes t16_decode_it(kprobe_opcode_t insn, struct arch_specific_insn *asi) { asi->insn_singlestep = t16_singlestep_it; return INSN_GOOD_NO_SLOT; } static void __kprobes t16_simulate_cond_branch(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long pc = thumb_probe_pc(p); long offset = insn & 0x7f; offset -= insn & 0x80; /* Apply sign bit */ regs->ARM_pc = pc + (offset * 2); } static enum kprobe_insn __kprobes t16_decode_cond_branch(kprobe_opcode_t insn, struct arch_specific_insn *asi) { int cc = (insn >> 8) & 0xf; asi->insn_check_cc = kprobe_condition_checks[cc]; asi->insn_handler = t16_simulate_cond_branch; return INSN_GOOD_NO_SLOT; } static void __kprobes t16_simulate_branch(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long pc = thumb_probe_pc(p); long offset = insn & 0x3ff; offset -= insn & 0x400; /* Apply sign bit */ regs->ARM_pc = pc + (offset * 2); } static unsigned long __kprobes t16_emulate_loregs(struct kprobe *p, struct pt_regs *regs) { unsigned long oldcpsr = regs->ARM_cpsr; unsigned long newcpsr; __asm__ __volatile__ ( "msr cpsr_fs, %[oldcpsr] \n\t" "ldmia %[regs], {r0-r7} \n\t" "blx %[fn] \n\t" "stmia %[regs], {r0-r7} \n\t" "mrs %[newcpsr], cpsr \n\t" : [newcpsr] "=r" (newcpsr) : [oldcpsr] "r" (oldcpsr), [regs] "r" (regs), [fn] "r" (p->ainsn.insn_fn) : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "lr", "memory", "cc" ); return (oldcpsr & ~APSR_MASK) | (newcpsr & APSR_MASK); } static void __kprobes t16_emulate_loregs_rwflags(struct kprobe *p, struct pt_regs *regs) { regs->ARM_cpsr = t16_emulate_loregs(p, regs); } static void __kprobes t16_emulate_loregs_noitrwflags(struct kprobe *p, struct pt_regs *regs) { unsigned long cpsr = t16_emulate_loregs(p, regs); if (!in_it_block(cpsr)) regs->ARM_cpsr = cpsr; } static void __kprobes t16_emulate_hiregs(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; unsigned long pc = thumb_probe_pc(p); int rdn = (insn & 0x7) | ((insn & 0x80) >> 4); int rm = (insn >> 3) & 0xf; register unsigned long rdnv asm("r1"); register unsigned long rmv asm("r0"); unsigned long cpsr = regs->ARM_cpsr; rdnv = (rdn == 15) ? pc : regs->uregs[rdn]; rmv = (rm == 15) ? pc : regs->uregs[rm]; __asm__ __volatile__ ( "msr cpsr_fs, %[cpsr] \n\t" "blx %[fn] \n\t" "mrs %[cpsr], cpsr \n\t" : "=r" (rdnv), [cpsr] "=r" (cpsr) : "0" (rdnv), "r" (rmv), "1" (cpsr), [fn] "r" (p->ainsn.insn_fn) : "lr", "memory", "cc" ); if (rdn == 15) rdnv &= ~1; regs->uregs[rdn] = rdnv; regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK); } static enum kprobe_insn __kprobes t16_decode_hiregs(kprobe_opcode_t insn, struct arch_specific_insn *asi) { insn &= ~0x00ff; insn |= 0x001; /* Set Rdn = R1 and Rm = R0 */ ((u16 *)asi->insn)[0] = insn; asi->insn_handler = t16_emulate_hiregs; return INSN_GOOD; } static void __kprobes t16_emulate_push(struct kprobe *p, struct pt_regs *regs) { __asm__ __volatile__ ( "ldr r9, [%[regs], #13*4] \n\t" "ldr r8, [%[regs], #14*4] \n\t" "ldmia %[regs], {r0-r7} \n\t" "blx %[fn] \n\t" "str r9, [%[regs], #13*4] \n\t" : : [regs] "r" (regs), [fn] "r" (p->ainsn.insn_fn) : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "lr", "memory", "cc" ); } static enum kprobe_insn __kprobes t16_decode_push(kprobe_opcode_t insn, struct arch_specific_insn *asi) { /* * To simulate a PUSH we use a Thumb-2 "STMDB R9!, {registers}" * and call it with R9=SP and LR in the register list represented * by R8. */ ((u16 *)asi->insn)[0] = 0xe929; /* 1st half STMDB R9!,{} */ ((u16 *)asi->insn)[1] = insn & 0x1ff; /* 2nd half (register list) */ asi->insn_handler = t16_emulate_push; return INSN_GOOD; } static void __kprobes t16_emulate_pop_nopc(struct kprobe *p, struct pt_regs *regs) { __asm__ __volatile__ ( "ldr r9, [%[regs], #13*4] \n\t" "ldmia %[regs], {r0-r7} \n\t" "blx %[fn] \n\t" "stmia %[regs], {r0-r7} \n\t" "str r9, [%[regs], #13*4] \n\t" : : [regs] "r" (regs), [fn] "r" (p->ainsn.insn_fn) : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r9", "lr", "memory", "cc" ); } static void __kprobes t16_emulate_pop_pc(struct kprobe *p, struct pt_regs *regs) { register unsigned long pc asm("r8"); __asm__ __volatile__ ( "ldr r9, [%[regs], #13*4] \n\t" "ldmia %[regs], {r0-r7} \n\t" "blx %[fn] \n\t" "stmia %[regs], {r0-r7} \n\t" "str r9, [%[regs], #13*4] \n\t" : "=r" (pc) : [regs] "r" (regs), [fn] "r" (p->ainsn.insn_fn) : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r9", "lr", "memory", "cc" ); bx_write_pc(pc, regs); } static enum kprobe_insn __kprobes t16_decode_pop(kprobe_opcode_t insn, struct arch_specific_insn *asi) { /* * To simulate a POP we use a Thumb-2 "LDMDB R9!, {registers}" * and call it with R9=SP and PC in the register list represented * by R8. */ ((u16 *)asi->insn)[0] = 0xe8b9; /* 1st half LDMIA R9!,{} */ ((u16 *)asi->insn)[1] = insn & 0x1ff; /* 2nd half (register list) */ asi->insn_handler = insn & 0x100 ? t16_emulate_pop_pc : t16_emulate_pop_nopc; return INSN_GOOD; } static const union decode_item t16_table_1011[] = { /* Miscellaneous 16-bit instructions */ /* ADD (SP plus immediate) 1011 0000 0xxx xxxx */ /* SUB (SP minus immediate) 1011 0000 1xxx xxxx */ DECODE_SIMULATE (0xff00, 0xb000, t16_simulate_add_sp_imm), /* CBZ 1011 00x1 xxxx xxxx */ /* CBNZ 1011 10x1 xxxx xxxx */ DECODE_SIMULATE (0xf500, 0xb100, t16_simulate_cbz), /* SXTH 1011 0010 00xx xxxx */ /* SXTB 1011 0010 01xx xxxx */ /* UXTH 1011 0010 10xx xxxx */ /* UXTB 1011 0010 11xx xxxx */ /* REV 1011 1010 00xx xxxx */ /* REV16 1011 1010 01xx xxxx */ /* ??? 1011 1010 10xx xxxx */ /* REVSH 1011 1010 11xx xxxx */ DECODE_REJECT (0xffc0, 0xba80), DECODE_EMULATE (0xf500, 0xb000, t16_emulate_loregs_rwflags), /* PUSH 1011 010x xxxx xxxx */ DECODE_CUSTOM (0xfe00, 0xb400, t16_decode_push), /* POP 1011 110x xxxx xxxx */ DECODE_CUSTOM (0xfe00, 0xbc00, t16_decode_pop), /* * If-Then, and hints * 1011 1111 xxxx xxxx */ /* YIELD 1011 1111 0001 0000 */ DECODE_OR (0xffff, 0xbf10), /* SEV 1011 1111 0100 0000 */ DECODE_EMULATE (0xffff, 0xbf40, kprobe_emulate_none), /* NOP 1011 1111 0000 0000 */ /* WFE 1011 1111 0010 0000 */ /* WFI 1011 1111 0011 0000 */ DECODE_SIMULATE (0xffcf, 0xbf00, kprobe_simulate_nop), /* Unassigned hints 1011 1111 xxxx 0000 */ DECODE_REJECT (0xff0f, 0xbf00), /* IT 1011 1111 xxxx xxxx */ DECODE_CUSTOM (0xff00, 0xbf00, t16_decode_it), /* SETEND 1011 0110 010x xxxx */ /* CPS 1011 0110 011x xxxx */ /* BKPT 1011 1110 xxxx xxxx */ /* And unallocated instructions... */ DECODE_END }; const union decode_item kprobe_decode_thumb16_table[] = { /* * Shift (immediate), add, subtract, move, and compare * 00xx xxxx xxxx xxxx */ /* CMP (immediate) 0010 1xxx xxxx xxxx */ DECODE_EMULATE (0xf800, 0x2800, t16_emulate_loregs_rwflags), /* ADD (register) 0001 100x xxxx xxxx */ /* SUB (register) 0001 101x xxxx xxxx */ /* LSL (immediate) 0000 0xxx xxxx xxxx */ /* LSR (immediate) 0000 1xxx xxxx xxxx */ /* ASR (immediate) 0001 0xxx xxxx xxxx */ /* ADD (immediate, Thumb) 0001 110x xxxx xxxx */ /* SUB (immediate, Thumb) 0001 111x xxxx xxxx */ /* MOV (immediate) 0010 0xxx xxxx xxxx */ /* ADD (immediate, Thumb) 0011 0xxx xxxx xxxx */ /* SUB (immediate, Thumb) 0011 1xxx xxxx xxxx */ DECODE_EMULATE (0xc000, 0x0000, t16_emulate_loregs_noitrwflags), /* * 16-bit Thumb data-processing instructions * 0100 00xx xxxx xxxx */ /* TST (register) 0100 0010 00xx xxxx */ DECODE_EMULATE (0xffc0, 0x4200, t16_emulate_loregs_rwflags), /* CMP (register) 0100 0010 10xx xxxx */ /* CMN (register) 0100 0010 11xx xxxx */ DECODE_EMULATE (0xff80, 0x4280, t16_emulate_loregs_rwflags), /* AND (register) 0100 0000 00xx xxxx */ /* EOR (register) 0100 0000 01xx xxxx */ /* LSL (register) 0100 0000 10xx xxxx */ /* LSR (register) 0100 0000 11xx xxxx */ /* ASR (register) 0100 0001 00xx xxxx */ /* ADC (register) 0100 0001 01xx xxxx */ /* SBC (register) 0100 0001 10xx xxxx */ /* ROR (register) 0100 0001 11xx xxxx */ /* RSB (immediate) 0100 0010 01xx xxxx */ /* ORR (register) 0100 0011 00xx xxxx */ /* MUL 0100 0011 00xx xxxx */ /* BIC (register) 0100 0011 10xx xxxx */ /* MVN (register) 0100 0011 10xx xxxx */ DECODE_EMULATE (0xfc00, 0x4000, t16_emulate_loregs_noitrwflags), /* * Special data instructions and branch and exchange * 0100 01xx xxxx xxxx */ /* BLX pc 0100 0111 1111 1xxx */ DECODE_REJECT (0xfff8, 0x47f8), /* BX (register) 0100 0111 0xxx xxxx */ /* BLX (register) 0100 0111 1xxx xxxx */ DECODE_SIMULATE (0xff00, 0x4700, t16_simulate_bxblx), /* ADD pc, pc 0100 0100 1111 1111 */ DECODE_REJECT (0xffff, 0x44ff), /* ADD (register) 0100 0100 xxxx xxxx */ /* CMP (register) 0100 0101 xxxx xxxx */ /* MOV (register) 0100 0110 xxxx xxxx */ DECODE_CUSTOM (0xfc00, 0x4400, t16_decode_hiregs), /* * Load from Literal Pool * LDR (literal) 0100 1xxx xxxx xxxx */ DECODE_SIMULATE (0xf800, 0x4800, t16_simulate_ldr_literal), /* * 16-bit Thumb Load/store instructions * 0101 xxxx xxxx xxxx * 011x xxxx xxxx xxxx * 100x xxxx xxxx xxxx */ /* STR (register) 0101 000x xxxx xxxx */ /* STRH (register) 0101 001x xxxx xxxx */ /* STRB (register) 0101 010x xxxx xxxx */ /* LDRSB (register) 0101 011x xxxx xxxx */ /* LDR (register) 0101 100x xxxx xxxx */ /* LDRH (register) 0101 101x xxxx xxxx */ /* LDRB (register) 0101 110x xxxx xxxx */ /* LDRSH (register) 0101 111x xxxx xxxx */ /* STR (immediate, Thumb) 0110 0xxx xxxx xxxx */ /* LDR (immediate, Thumb) 0110 1xxx xxxx xxxx */ /* STRB (immediate, Thumb) 0111 0xxx xxxx xxxx */ /* LDRB (immediate, Thumb) 0111 1xxx xxxx xxxx */ DECODE_EMULATE (0xc000, 0x4000, t16_emulate_loregs_rwflags), /* STRH (immediate, Thumb) 1000 0xxx xxxx xxxx */ /* LDRH (immediate, Thumb) 1000 1xxx xxxx xxxx */ DECODE_EMULATE (0xf000, 0x8000, t16_emulate_loregs_rwflags), /* STR (immediate, Thumb) 1001 0xxx xxxx xxxx */ /* LDR (immediate, Thumb) 1001 1xxx xxxx xxxx */ DECODE_SIMULATE (0xf000, 0x9000, t16_simulate_ldrstr_sp_relative), /* * Generate PC-/SP-relative address * ADR (literal) 1010 0xxx xxxx xxxx * ADD (SP plus immediate) 1010 1xxx xxxx xxxx */ DECODE_SIMULATE (0xf000, 0xa000, t16_simulate_reladr), /* * Miscellaneous 16-bit instructions * 1011 xxxx xxxx xxxx */ DECODE_TABLE (0xf000, 0xb000, t16_table_1011), /* STM 1100 0xxx xxxx xxxx */ /* LDM 1100 1xxx xxxx xxxx */ DECODE_EMULATE (0xf000, 0xc000, t16_emulate_loregs_rwflags), /* * Conditional branch, and Supervisor Call */ /* Permanently UNDEFINED 1101 1110 xxxx xxxx */ /* SVC 1101 1111 xxxx xxxx */ DECODE_REJECT (0xfe00, 0xde00), /* Conditional branch 1101 xxxx xxxx xxxx */ DECODE_CUSTOM (0xf000, 0xd000, t16_decode_cond_branch), /* * Unconditional branch * B 1110 0xxx xxxx xxxx */ DECODE_SIMULATE (0xf800, 0xe000, t16_simulate_branch), DECODE_END }; static unsigned long __kprobes thumb_check_cc(unsigned long cpsr) { if (unlikely(in_it_block(cpsr))) return kprobe_condition_checks[current_cond(cpsr)](cpsr); return true; } static void __kprobes thumb16_singlestep(struct kprobe *p, struct pt_regs *regs) { regs->ARM_pc += 2; p->ainsn.insn_handler(p, regs); regs->ARM_cpsr = it_advance(regs->ARM_cpsr); } static void __kprobes thumb32_singlestep(struct kprobe *p, struct pt_regs *regs) { regs->ARM_pc += 4; p->ainsn.insn_handler(p, regs); regs->ARM_cpsr = it_advance(regs->ARM_cpsr); } enum kprobe_insn __kprobes thumb16_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi) { asi->insn_singlestep = thumb16_singlestep; asi->insn_check_cc = thumb_check_cc; return kprobe_decode_insn(insn, asi, kprobe_decode_thumb16_table, true); } enum kprobe_insn __kprobes thumb32_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi) { asi->insn_singlestep = thumb32_singlestep; asi->insn_check_cc = thumb_check_cc; return kprobe_decode_insn(insn, asi, kprobe_decode_thumb32_table, true); }