From 34e7317d6ae8f6111ac449444f22e14f4a14ebfd Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Mon, 31 Mar 2014 19:38:09 +0200 Subject: [PATCH] uprobes/x86: move the UPROBE_FIX_{RIP,IP,CALL} code at the end of pre/post hooks No functional changes. Preparation to simplify the review of the next change. Just reorder the code in arch_uprobe_pre/post_xol() functions so that UPROBE_FIX_{RIP_*,IP,CALL} logic goes to the end. Also change arch_uprobe_pre_xol() to use utask instead of autask, to make the code more symmetrical with arch_uprobe_post_xol(). Signed-off-by: Oleg Nesterov Reviewed-by: Masami Hiramatsu Reviewed-by: Jim Keniston Acked-by: Srikar Dronamraju --- arch/x86/kernel/uprobes.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c index c52c30fa7871..3bb4198aa588 100644 --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -474,19 +474,18 @@ int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, */ int arch_uprobe_pre_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) { - struct arch_uprobe_task *autask; + struct uprobe_task *utask = current->utask; - autask = ¤t->utask->autask; - autask->saved_trap_nr = current->thread.trap_nr; + regs->ip = utask->xol_vaddr; + utask->autask.saved_trap_nr = current->thread.trap_nr; current->thread.trap_nr = UPROBE_TRAP_NR; - regs->ip = current->utask->xol_vaddr; - pre_xol_rip_insn(auprobe, regs, autask); - autask->saved_tf = !!(regs->flags & X86_EFLAGS_TF); + utask->autask.saved_tf = !!(regs->flags & X86_EFLAGS_TF); regs->flags |= X86_EFLAGS_TF; if (test_tsk_thread_flag(current, TIF_BLOCKSTEP)) set_task_blockstep(current, false); + pre_xol_rip_insn(auprobe, regs, &utask->autask); return 0; } @@ -560,22 +559,13 @@ bool arch_uprobe_xol_was_trapped(struct task_struct *t) */ int arch_uprobe_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) { - struct uprobe_task *utask; + struct uprobe_task *utask = current->utask; long correction; int result = 0; WARN_ON_ONCE(current->thread.trap_nr != UPROBE_TRAP_NR); - utask = current->utask; current->thread.trap_nr = utask->autask.saved_trap_nr; - correction = (long)(utask->vaddr - utask->xol_vaddr); - handle_riprel_post_xol(auprobe, regs, &correction); - if (auprobe->fixups & UPROBE_FIX_IP) - regs->ip += correction; - - if (auprobe->fixups & UPROBE_FIX_CALL) - result = adjust_ret_addr(regs->sp, correction); - /* * arch_uprobe_pre_xol() doesn't save the state of TIF_BLOCKSTEP * so we can get an extra SIGTRAP if we do not clear TF. We need @@ -586,6 +576,14 @@ int arch_uprobe_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) else if (!(auprobe->fixups & UPROBE_FIX_SETF)) regs->flags &= ~X86_EFLAGS_TF; + correction = (long)(utask->vaddr - utask->xol_vaddr); + handle_riprel_post_xol(auprobe, regs, &correction); + if (auprobe->fixups & UPROBE_FIX_IP) + regs->ip += correction; + + if (auprobe->fixups & UPROBE_FIX_CALL) + result = adjust_ret_addr(regs->sp, correction); + return result; } -- 2.20.1