ARM: kprobes: Decode 32-bit Thumb table branch instructions

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
This commit is contained in:
Jon Medhurst 2011-07-03 14:26:16 +01:00 committed by Tixy
parent b48354d358
commit dd212bd3cb

View File

@ -37,6 +37,26 @@ 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)
halfwords = ((u16 *)rnv)[rmv];
else
halfwords = ((u8 *)rnv)[rmv];
regs->ARM_pc = pc + 2 * halfwords;
}
static enum kprobe_insn __kprobes
t32_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi)
{
@ -117,6 +137,11 @@ static const union decode_item t32_table_1110_100x_x1xx[] = {
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 */