diff options
| author | Jon Medhurst <tixy@yxit.co.uk> | 2011-04-08 16:32:54 +0200 |
|---|---|---|
| committer | Nicolas Pitre <nicolas.pitre@linaro.org> | 2011-04-29 05:40:56 +0200 |
| commit | 6823fc85fcfba11675f2027aadf2d5291c6f351b (patch) | |
| tree | 44da95dd42e7b98e475a644f1aaac46310b69492 /arch/arm/kernel/kprobes-decode.c | |
| parent | ARM: kprobes: Reject probing of STREX and LDREX instructions (diff) | |
| download | linux-6823fc85fcfba11675f2027aadf2d5291c6f351b.tar.xz linux-6823fc85fcfba11675f2027aadf2d5291c6f351b.zip | |
ARM: kprobes: Fix emulation of LDRH, STRH, LDRSB and LDRSH instructions
The decoding of these instructions got the register indexed and
immediate indexed forms the wrong way around, causing incorrect
emulation.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Diffstat (limited to 'arch/arm/kernel/kprobes-decode.c')
| -rw-r--r-- | arch/arm/kernel/kprobes-decode.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/arm/kernel/kprobes-decode.c b/arch/arm/kernel/kprobes-decode.c index c24e21ec427f..348ff47acd06 100644 --- a/arch/arm/kernel/kprobes-decode.c +++ b/arch/arm/kernel/kprobes-decode.c @@ -883,11 +883,12 @@ emulate_alu_tests(struct kprobe *p, struct pt_regs *regs) static enum kprobe_insn __kprobes prep_emulate_ldr_str(kprobe_opcode_t insn, struct arch_specific_insn *asi) { - int ibit = (insn & (1 << 26)) ? 25 : 22; + int not_imm = (insn & (1 << 26)) ? (insn & (1 << 25)) + : (~insn & (1 << 22)); insn &= 0xfff00fff; insn |= 0x00001000; /* Rn = r0, Rd = r1 */ - if (insn & (1 << ibit)) { + if (not_imm) { insn &= ~0xf; insn |= 2; /* Rm = r2 */ } |