Messages in this thread Patch in this message | | | From | Pratyush Anand <> | Subject | [RFC PATCH V2 10/10] arm64: uprobes: check conditions before simulating instructions | Date | Thu, 18 Jun 2015 09:28:57 +0530 |
| |
From: Steve Capper <steve.capper@linaro.org>
Currently uprobes just simulates any instruction that it can't in place execute. This can lead to unpredictable behaviour if the execution condition fails and the instruction wouldn't otherwise have been executed.
This patch adds the condition check
Signed-off-by: Steve Capper <steve.capper@linaro.org> --- arch/arm64/kernel/uprobes.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kernel/uprobes.c b/arch/arm64/kernel/uprobes.c index 2cc9114deac2..a6d12b81e9ae 100644 --- a/arch/arm64/kernel/uprobes.c +++ b/arch/arm64/kernel/uprobes.c @@ -119,15 +119,22 @@ bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs) { kprobe_opcode_t insn; unsigned long addr; + struct arch_specific_insn *ainsn; if (!auprobe->simulate) return false; insn = *(kprobe_opcode_t *)(&auprobe->insn[0]); addr = instruction_pointer(regs); + ainsn = &auprobe->ainsn; + + if (ainsn->handler) { + if (!ainsn->check_condn || ainsn->check_condn(insn, ainsn, regs)) + ainsn->handler(insn, addr, regs); + else + instruction_pointer_set(regs, instruction_pointer(regs) + 4); + } - if (auprobe->ainsn.handler) - auprobe->ainsn.handler(insn, addr, regs); return true; } -- 2.1.0
| |