From 29b6cd794e73eea7600541d06288a09861ffecb0 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 18 Dec 2007 18:05:58 +0100 Subject: [PATCH] x86: jprobe bugfix jprobe for x86-64 may cause kernel page fault when the jprobe_return() is called from incorrect function. - Use jprobe_saved_regs instead getting it from stack. (Especially on x86-64, it may get incorrect data, because pt_regs can not be get by using container_of(rsp)) - Change the type of stack pointer to unsigned long *. Signed-off-by: Masami Hiramatsu Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/kprobes_32.c | 4 +--- arch/x86/kernel/kprobes_64.c | 6 ++---- include/asm-x86/kprobes_32.h | 2 +- include/asm-x86/kprobes_64.h | 2 +- 4 files changed, 5 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/kprobes_32.c b/arch/x86/kernel/kprobes_32.c index d87a523070..3a020f79f8 100644 --- a/arch/x86/kernel/kprobes_32.c +++ b/arch/x86/kernel/kprobes_32.c @@ -727,9 +727,7 @@ int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) if ((addr > (u8 *) jprobe_return) && (addr < (u8 *) jprobe_return_end)) { if (®s->esp != kcb->jprobe_saved_esp) { - struct pt_regs *saved_regs = - container_of(kcb->jprobe_saved_esp, - struct pt_regs, esp); + struct pt_regs *saved_regs = &kcb->jprobe_saved_regs; printk("current esp %p does not match saved esp %p\n", ®s->esp, kcb->jprobe_saved_esp); printk("Saved registers for jprobe %p\n", jp); diff --git a/arch/x86/kernel/kprobes_64.c b/arch/x86/kernel/kprobes_64.c index 0c46764458..a575059fb4 100644 --- a/arch/x86/kernel/kprobes_64.c +++ b/arch/x86/kernel/kprobes_64.c @@ -716,10 +716,8 @@ int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) struct jprobe *jp = container_of(p, struct jprobe, kp); if ((addr > (u8 *) jprobe_return) && (addr < (u8 *) jprobe_return_end)) { - if ((long *)regs->rsp != kcb->jprobe_saved_rsp) { - struct pt_regs *saved_regs = - container_of(kcb->jprobe_saved_rsp, - struct pt_regs, rsp); + if ((unsigned long *)regs->rsp != kcb->jprobe_saved_rsp) { + struct pt_regs *saved_regs = &kcb->jprobe_saved_regs; printk("current rsp %p does not match saved rsp %p\n", (long *)regs->rsp, kcb->jprobe_saved_rsp); printk("Saved registers for jprobe %p\n", jp); diff --git a/include/asm-x86/kprobes_32.h b/include/asm-x86/kprobes_32.h index b772d5b386..9fe8f3bddf 100644 --- a/include/asm-x86/kprobes_32.h +++ b/include/asm-x86/kprobes_32.h @@ -73,7 +73,7 @@ struct kprobe_ctlblk { unsigned long kprobe_status; unsigned long kprobe_old_eflags; unsigned long kprobe_saved_eflags; - long *jprobe_saved_esp; + unsigned long *jprobe_saved_esp; struct pt_regs jprobe_saved_regs; kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE]; struct prev_kprobe prev_kprobe; diff --git a/include/asm-x86/kprobes_64.h b/include/asm-x86/kprobes_64.h index 53f4d85073..743d76218f 100644 --- a/include/asm-x86/kprobes_64.h +++ b/include/asm-x86/kprobes_64.h @@ -66,7 +66,7 @@ struct kprobe_ctlblk { unsigned long kprobe_status; unsigned long kprobe_old_rflags; unsigned long kprobe_saved_rflags; - long *jprobe_saved_rsp; + unsigned long *jprobe_saved_rsp; struct pt_regs jprobe_saved_regs; kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE]; struct prev_kprobe prev_kprobe; -- 2.39.5