#include <asm/cacheflush.h>
#include <asm/kdebug.h>
#include <asm/desc.h>
+#include <asm/uaccess.h>
void jprobe_return_end(void);
DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
/* insert a jmp code */
-static inline void set_jmp_op(void *from, void *to)
+static __always_inline void set_jmp_op(void *from, void *to)
{
struct __arch_jmp_op {
char op;
/*
* returns non-zero if opcodes can be boosted.
*/
-static inline int can_boost(kprobe_opcode_t opcode)
+static __always_inline int can_boost(kprobe_opcode_t opcode)
{
switch (opcode & 0xf0 ) {
case 0x70:
/*
* returns non-zero if opcode modifies the interrupt flag.
*/
-static inline int is_IF_modifier(kprobe_opcode_t opcode)
+static int __kprobes is_IF_modifier(kprobe_opcode_t opcode)
{
switch (opcode) {
case 0xfa: /* cli */
mutex_unlock(&kprobe_mutex);
}
-static inline void save_previous_kprobe(struct kprobe_ctlblk *kcb)
+static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb)
{
kcb->prev_kprobe.kp = kprobe_running();
kcb->prev_kprobe.status = kcb->kprobe_status;
kcb->prev_kprobe.saved_eflags = kcb->kprobe_saved_eflags;
}
-static inline void restore_previous_kprobe(struct kprobe_ctlblk *kcb)
+static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb)
{
__get_cpu_var(current_kprobe) = kcb->prev_kprobe.kp;
kcb->kprobe_status = kcb->prev_kprobe.status;
kcb->kprobe_saved_eflags = kcb->prev_kprobe.saved_eflags;
}
-static inline void set_current_kprobe(struct kprobe *p, struct pt_regs *regs,
+static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs,
struct kprobe_ctlblk *kcb)
{
__get_cpu_var(current_kprobe) = p;
kcb->kprobe_saved_eflags &= ~IF_MASK;
}
-static inline void prepare_singlestep(struct kprobe *p, struct pt_regs *regs)
+static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs)
{
regs->eflags |= TF_MASK;
regs->eflags &= ~IF_MASK;
kcb->kprobe_status = KPROBE_REENTER;
return 1;
} else {
- if (regs->eflags & VM_MASK) {
- /* We are in virtual-8086 mode. Return 0 */
- goto no_kprobe;
- }
if (*addr != BREAKPOINT_INSTRUCTION) {
/* The breakpoint instruction was removed by
* another cpu right after we hit, no further
p = get_kprobe(addr);
if (!p) {
- if (regs->eflags & VM_MASK) {
- /* We are in virtual-8086 mode. Return 0 */
- goto no_kprobe;
- }
-
if (*addr != BREAKPOINT_INSTRUCTION) {
/*
* The breakpoint instruction was removed right
*tos &= ~(TF_MASK | IF_MASK);
*tos |= kcb->kprobe_old_eflags;
break;
- case 0xc3: /* ret/lret */
- case 0xcb:
- case 0xc2:
+ case 0xc2: /* iret/ret/lret */
+ case 0xc3:
case 0xca:
+ case 0xcb:
+ case 0xcf:
case 0xea: /* jmp absolute -- eip is correct */
/* eip is already adjusted, no more changes required */
p->ainsn.boostable = 1;
case 0xe8: /* call relative - Fix return addr */
*tos = orig_eip + (*tos - copy_eip);
break;
+ case 0x9a: /* call absolute -- same as call absolute, indirect */
+ *tos = orig_eip + (*tos - copy_eip);
+ goto no_change;
case 0xff:
if ((p->ainsn.insn[1] & 0x30) == 0x10) {
- /* call absolute, indirect */
/*
+ * call absolute, indirect
* Fix return addr; eip is correct.
* But this is not boostable
*/
* Interrupts are disabled on entry as trap1 is an interrupt gate and they
* remain disabled thoroughout this function.
*/
-static inline int post_kprobe_handler(struct pt_regs *regs)
+static int __kprobes post_kprobe_handler(struct pt_regs *regs)
{
struct kprobe *cur = kprobe_running();
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
return 1;
}
-static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
+static int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
{
struct kprobe *cur = kprobe_running();
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
- if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
- return 1;
-
- if (kcb->kprobe_status & KPROBE_HIT_SS) {
- resume_execution(cur, regs, kcb);
+ switch(kcb->kprobe_status) {
+ case KPROBE_HIT_SS:
+ case KPROBE_REENTER:
+ /*
+ * We are here because the instruction being single
+ * stepped caused a page fault. We reset the current
+ * kprobe and the eip points back to the probe address
+ * and allow the page fault handler to continue as a
+ * normal page fault.
+ */
+ regs->eip = (unsigned long)cur->addr;
regs->eflags |= kcb->kprobe_old_eflags;
-
- reset_current_kprobe();
+ if (kcb->kprobe_status == KPROBE_REENTER)
+ restore_previous_kprobe(kcb);
+ else
+ reset_current_kprobe();
preempt_enable_no_resched();
+ break;
+ case KPROBE_HIT_ACTIVE:
+ case KPROBE_HIT_SSDONE:
+ /*
+ * We increment the nmissed count for accounting,
+ * we can also use npre/npostfault count for accouting
+ * these specific fault cases.
+ */
+ kprobes_inc_nmissed_count(cur);
+
+ /*
+ * We come here because instructions in the pre/post
+ * handler caused the page_fault, this could happen
+ * if handler tries to access user space by
+ * copy_from_user(), get_user() etc. Let the
+ * user-specified handler try to fix it first.
+ */
+ if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
+ return 1;
+
+ /*
+ * In case the user-specified fault handler returned
+ * zero, try to fix up.
+ */
+ if (fixup_exception(regs))
+ return 1;
+
+ /*
+ * fixup_exception() could not handle it,
+ * Let do_page_fault() fix it.
+ */
+ break;
+ default:
+ break;
}
return 0;
}