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path: root/arch/i386/kernel/kprobes.c
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Diffstat (limited to 'arch/i386/kernel/kprobes.c')
-rw-r--r--arch/i386/kernel/kprobes.c26
1 files changed, 17 insertions, 9 deletions
diff --git a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
index d98e44b16fe..af1d5334499 100644
--- a/arch/i386/kernel/kprobes.c
+++ b/arch/i386/kernel/kprobes.c
@@ -184,7 +184,7 @@ void __kprobes arch_disarm_kprobe(struct kprobe *p)
void __kprobes arch_remove_kprobe(struct kprobe *p)
{
mutex_lock(&kprobe_mutex);
- free_insn_slot(p->ainsn.insn);
+ free_insn_slot(p->ainsn.insn, (p->ainsn.boostable == 1));
mutex_unlock(&kprobe_mutex);
}
@@ -333,7 +333,7 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
return 1;
ss_probe:
-#ifndef CONFIG_PREEMPT
+#if !defined(CONFIG_PREEMPT) || defined(CONFIG_PM)
if (p->ainsn.boostable == 1 && !p->post_handler){
/* Boost up -- we can execute copied instructions directly */
reset_current_kprobe();
@@ -361,8 +361,11 @@ no_kprobe:
asm volatile ( ".global kretprobe_trampoline\n"
"kretprobe_trampoline: \n"
" pushf\n"
- /* skip cs, eip, orig_eax, es, ds */
- " subl $20, %esp\n"
+ /* skip cs, eip, orig_eax */
+ " subl $12, %esp\n"
+ " pushl %gs\n"
+ " pushl %ds\n"
+ " pushl %es\n"
" pushl %eax\n"
" pushl %ebp\n"
" pushl %edi\n"
@@ -373,10 +376,10 @@ no_kprobe:
" movl %esp, %eax\n"
" call trampoline_handler\n"
/* move eflags to cs */
- " movl 48(%esp), %edx\n"
- " movl %edx, 44(%esp)\n"
+ " movl 52(%esp), %edx\n"
+ " movl %edx, 48(%esp)\n"
/* save true return address on eflags */
- " movl %eax, 48(%esp)\n"
+ " movl %eax, 52(%esp)\n"
" popl %ebx\n"
" popl %ecx\n"
" popl %edx\n"
@@ -384,8 +387,8 @@ no_kprobe:
" popl %edi\n"
" popl %ebp\n"
" popl %eax\n"
- /* skip eip, orig_eax, es, ds */
- " addl $16, %esp\n"
+ /* skip eip, orig_eax, es, ds, gs */
+ " addl $20, %esp\n"
" popf\n"
" ret\n");
}
@@ -404,6 +407,10 @@ fastcall void *__kprobes trampoline_handler(struct pt_regs *regs)
INIT_HLIST_HEAD(&empty_rp);
spin_lock_irqsave(&kretprobe_lock, flags);
head = kretprobe_inst_table_head(current);
+ /* fixup registers */
+ regs->xcs = __KERNEL_CS;
+ regs->eip = trampoline_address;
+ regs->orig_eax = 0xffffffff;
/*
* It is possible to have multiple instances associated with a given
@@ -425,6 +432,7 @@ fastcall void *__kprobes trampoline_handler(struct pt_regs *regs)
if (ri->rp && ri->rp->handler){
__get_cpu_var(current_kprobe) = &ri->rp->kp;
+ get_kprobe_ctlblk()->kprobe_status = KPROBE_HIT_ACTIVE;
ri->rp->handler(ri, regs);
__get_cpu_var(current_kprobe) = NULL;
}