Commit-ID: 6cc5e7ff2c38641060f20786a5caf2815edbca5f Gitweb: http://git.kernel.org/tip/6cc5e7ff2c38641060f20786a5caf2815edbca5f Author: Oleg Nesterov <oleg@xxxxxxxxxx> AuthorDate: Mon, 7 Apr 2014 16:22:58 +0200 Committer: Oleg Nesterov <oleg@xxxxxxxxxx> CommitDate: Thu, 17 Apr 2014 21:58:25 +0200 uprobes/x86: Emulate relative conditional "near" jmp's Change branch_setup_xol_ops() to simply use opc1 = OPCODE2(insn) - 0x10 if OPCODE1() == 0x0f; this matches the "short" jmp which checks the same condition. Thanks to lib/insn.c, it does the rest correctly. branch->ilen/offs are correct no matter if this jmp is "near" or "short". Reported-by: Jonathan Lebon <jlebon@xxxxxxxxxx> Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Reviewed-by: Jim Keniston <jkenisto@xxxxxxxxxx> --- arch/x86/kernel/uprobes.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c index 0460d04..ace2291 100644 --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -599,6 +599,14 @@ static int branch_setup_xol_ops(struct arch_uprobe *auprobe, struct insn *insn) branch_clear_offset(auprobe, insn); break; + case 0x0f: + if (insn->opcode.nbytes != 2) + return -ENOSYS; + /* + * If it is a "near" conditional jmp, OPCODE2() - 0x10 matches + * OPCODE1() of the "short" jmp which checks the same condition. + */ + opc1 = OPCODE2(insn) - 0x10; default: if (!is_cond_jmp_opcode(opc1)) return -ENOSYS; -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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