diff options
| -rw-r--r-- | arch/arm/kernel/kprobes-arm.c | 58 | ||||
| -rw-r--r-- | arch/arm/kernel/kprobes-common.c | 70 | ||||
| -rw-r--r-- | arch/arm/kernel/kprobes.h | 3 |
3 files changed, 80 insertions, 51 deletions
diff --git a/arch/arm/kernel/kprobes-arm.c b/arch/arm/kernel/kprobes-arm.c index a1143e86a09a..c6f2c693b1b6 100644 --- a/arch/arm/kernel/kprobes-arm.c +++ b/arch/arm/kernel/kprobes-arm.c @@ -437,54 +437,6 @@ static void __kprobes simulate_mrs(struct kprobe *p, struct pt_regs *regs) regs->uregs[rd] = regs->ARM_cpsr & mask; } -static void __kprobes simulate_ldm1stm1(struct kprobe *p, struct pt_regs *regs) -{ - kprobe_opcode_t insn = p->opcode; - int rn = (insn >> 16) & 0xf; - int lbit = insn & (1 << 20); - int wbit = insn & (1 << 21); - int ubit = insn & (1 << 23); - int pbit = insn & (1 << 24); - long *addr = (long *)regs->uregs[rn]; - int reg_bit_vector; - int reg_count; - - reg_count = 0; - reg_bit_vector = insn & 0xffff; - while (reg_bit_vector) { - reg_bit_vector &= (reg_bit_vector - 1); - ++reg_count; - } - - if (!ubit) - addr -= reg_count; - addr += (!pbit == !ubit); - - reg_bit_vector = insn & 0xffff; - while (reg_bit_vector) { - int reg = __ffs(reg_bit_vector); - reg_bit_vector &= (reg_bit_vector - 1); - if (lbit) - regs->uregs[reg] = *addr++; - else - *addr++ = regs->uregs[reg]; - } - - if (wbit) { - if (!ubit) - addr -= reg_count; - addr -= (!pbit == !ubit); - regs->uregs[rn] = (long)addr; - } -} - -static void __kprobes simulate_stm1_pc(struct kprobe *p, struct pt_regs *regs) -{ - regs->ARM_pc = (long)p->addr + str_pc_offset; - simulate_ldm1stm1(p, regs); - regs->ARM_pc = (long)p->addr + 4; -} - static void __kprobes simulate_mov_ipsp(struct kprobe *p, struct pt_regs *regs) { regs->uregs[12] = regs->uregs[13]; @@ -1463,9 +1415,13 @@ space_cccc_100x(kprobe_opcode_t insn, struct arch_specific_insn *asi) /* LDM(1) : cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */ /* STM(1) : cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */ - asi->insn_handler = ((insn & 0x108000) == 0x008000) ? /* STM & R15 */ - simulate_stm1_pc : simulate_ldm1stm1; - return INSN_GOOD_NO_SLOT; + + /* + * Make the instruction unconditional because the new emulation + * functions don't bother to setup the PSR context. + */ + insn = (insn | 0xe0000000) & ~0x10000000; + return kprobe_decode_ldmstm(insn, asi); } static enum kprobe_insn __kprobes diff --git a/arch/arm/kernel/kprobes-common.c b/arch/arm/kernel/kprobes-common.c index 86fdc4c4c2ce..43d663cafdd1 100644 --- a/arch/arm/kernel/kprobes-common.c +++ b/arch/arm/kernel/kprobes-common.c @@ -166,6 +166,76 @@ void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs) p->ainsn.insn_fn(); } +static void __kprobes simulate_ldm1stm1(struct kprobe *p, struct pt_regs *regs) +{ + kprobe_opcode_t insn = p->opcode; + int rn = (insn >> 16) & 0xf; + int lbit = insn & (1 << 20); + int wbit = insn & (1 << 21); + int ubit = insn & (1 << 23); + int pbit = insn & (1 << 24); + long *addr = (long *)regs->uregs[rn]; + int reg_bit_vector; + int reg_count; + + reg_count = 0; + reg_bit_vector = insn & 0xffff; + while (reg_bit_vector) { + reg_bit_vector &= (reg_bit_vector - 1); + ++reg_count; + } + + if (!ubit) + addr -= reg_count; + addr += (!pbit == !ubit); + + reg_bit_vector = insn & 0xffff; + while (reg_bit_vector) { + int reg = __ffs(reg_bit_vector); + reg_bit_vector &= (reg_bit_vector - 1); + if (lbit) + regs->uregs[reg] = *addr++; + else + *addr++ = regs->uregs[reg]; + } + + if (wbit) { + if (!ubit) + addr -= reg_count; + addr -= (!pbit == !ubit); + regs->uregs[rn] = (long)addr; + } +} + +static void __kprobes simulate_stm1_pc(struct kprobe *p, struct pt_regs *regs) +{ + regs->ARM_pc = (long)p->addr + str_pc_offset; + simulate_ldm1stm1(p, regs); + regs->ARM_pc = (long)p->addr + 4; +} + +static void __kprobes simulate_ldm1_pc(struct kprobe *p, struct pt_regs *regs) +{ + simulate_ldm1stm1(p, regs); + load_write_pc(regs->ARM_pc, regs); +} + +enum kprobe_insn __kprobes +kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi) +{ + kprobe_insn_handler_t *handler = 0; + unsigned reglist = insn & 0xffff; + int is_ldm = insn & 0x100000; + + if (reglist & 0x8000) + handler = is_ldm ? simulate_ldm1_pc : simulate_stm1_pc; + else + handler = simulate_ldm1stm1; + asi->insn_handler = handler; + return INSN_GOOD_NO_SLOT; +} + + /* * Prepare an instruction slot to receive an instruction for emulating. * This is done by placing a subroutine return after the location where the diff --git a/arch/arm/kernel/kprobes.h b/arch/arm/kernel/kprobes.h index 5d6bf0d0a18a..c442852e65e4 100644 --- a/arch/arm/kernel/kprobes.h +++ b/arch/arm/kernel/kprobes.h @@ -136,6 +136,9 @@ static inline void __kprobes load_write_pc(long pcv, struct pt_regs *regs) void __kprobes kprobe_simulate_nop(struct kprobe *p, struct pt_regs *regs); void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs); +enum kprobe_insn __kprobes +kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi); + /* * Test if load/store instructions writeback the address register. * if P (bit 24) == 0 or W (bit 21) == 1 |
