diff options
Diffstat (limited to 'arch/arm/kernel/kprobes-common.c')
-rw-r--r-- | arch/arm/kernel/kprobes-common.c | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/arm/kernel/kprobes-common.c b/arch/arm/kernel/kprobes-common.c index 86fdc4c4c2c..43d663cafdd 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 |