.pre_handler = trampoline_probe_handler
};
-// is instruction Thumb2 and NOT a branch, etc...
-int isThumb2(kprobe_opcode_t insn)
-{
- if(( (insn & 0xf800) == 0xe800 ||
- (insn & 0xf800) == 0xf000 ||
- (insn & 0xf800) == 0xf800)) return 1;
- return 0;
-}
-EXPORT_SYMBOL_GPL(isThumb2);
-
int prep_pc_dep_insn_execbuf(kprobe_opcode_t *insns, kprobe_opcode_t insn, int uregs)
{
int i;
__get_cpu_var(current_kprobe) = p;
DBPRINTF ("set_current_kprobe: p=%p addr=%p\n", p, p->addr);
}
-
-static int check_validity_insn(struct kprobe *p, struct pt_regs *regs, struct task_struct *task)
-{
- struct kprobe *kp;
-
- if (unlikely(thumb_mode(regs))) {
- if (p->safe_thumb != -1) {
- p->ainsn.insn = p->ainsn.insn_thumb;
- list_for_each_entry_rcu(kp, &p->list, list) {
- kp->ainsn.insn = p->ainsn.insn_thumb;
- }
- } else {
- printk("Error in %s at %d: we are in thumb mode (!) and check instruction was fail \
- (%0lX instruction at %p address)!\n", __FILE__, __LINE__, p->opcode, p->addr);
- // Test case when we do our actions on already running application
- arch_disarm_uprobe(p, task);
- return -1;
- }
- } else {
- if (p->safe_arm != -1) {
- p->ainsn.insn = p->ainsn.insn_arm;
- list_for_each_entry_rcu(kp, &p->list, list) {
- kp->ainsn.insn = p->ainsn.insn_arm;
- }
- } else {
- printk("Error in %s at %d: we are in arm mode (!) and check instruction was fail \
- (%0lX instruction at %p address)!\n", __FILE__, __LINE__, p->opcode, p->addr);
- // Test case when we do our actions on already running application
- arch_disarm_uprobe(p, task);
- return -1;
- }
- }
-
- return 0;
-}
+EXPORT_SYMBOL_GPL(set_current_kprobe);
#ifdef TRAP_OVERHEAD_DEBUG
static unsigned long trap_handler_counter_debug = 0;
{
int err_out = 0;
char *msg_out = NULL;
- unsigned long user_m = user_mode(regs);
- pid_t tgid = (user_m) ? current->tgid : 0;
kprobe_opcode_t *addr = (kprobe_opcode_t *) (regs->ARM_pc);
struct kprobe *p = NULL, *p_run = NULL;
#endif
preempt_disable();
-// printk("### kprobe_handler: task[tgid=%u (%s)] addr=%p\n", tgid, current->comm, addr);
- p = get_kprobe(addr, tgid);
-
- if (user_m && p && (check_validity_insn(p, regs, current) != 0)) {
- goto no_kprobe_live;
- }
+ p = get_kprobe(addr, 0);
/* We're in an interrupt, but this is clear and BUG()-safe. */
kcb = get_kprobe_ctlblk ();
DBPRINTF("lock???");
if (p)
{
- if (!tgid && (addr == (kprobe_opcode_t *)kretprobe_trampoline)) {
+ if (addr == (kprobe_opcode_t *)kretprobe_trampoline) {
save_previous_kprobe(kcb, p_run);
kcb->kprobe_status = KPROBE_REENTER;
reenter = 1;
goto out;
}
} else {
- if(tgid) { //we can reenter probe upon uretprobe exception
- DBPRINTF ("check for UNDEF_INSTRUCTION %p\n", addr);
- // UNDEF_INSTRUCTION from user space
-
- p = get_kprobe_by_insn_slot(addr, tgid, regs);
- if (p) {
- save_previous_kprobe(kcb, p_run);
- kcb->kprobe_status = KPROBE_REENTER;
- reenter = 1;
- retprobe = 1;
- DBPRINTF ("uretprobe %p\n", addr);
- }
- }
if(!p) {
p = p_run;
DBPRINTF ("kprobe_running !!! p = 0x%p p->break_handler = 0x%p", p, p->break_handler);
goto ss_probe;
} */
DBPRINTF ("unknown uprobe at %p cur at %p/%p\n", addr, p->addr, p->ainsn.insn);
- if (tgid)
- ssaddr = p->ainsn.insn + UPROBES_TRAMP_SS_BREAK_IDX;
- else
- ssaddr = p->ainsn.insn + KPROBES_TRAMP_SS_BREAK_IDX;
+ ssaddr = p->ainsn.insn + KPROBES_TRAMP_SS_BREAK_IDX;
if (addr == ssaddr) {
regs->ARM_pc = (unsigned long) (p->addr + 1);
DBPRINTF ("finish step at %p cur at %p/%p, redirect to %lx\n", addr, p->addr, p->ainsn.insn, regs->ARM_pc);
}
if (!p) {
- if (tgid) {
- DBPRINTF ("search UNDEF_INSTRUCTION %p\n", addr);
- // UNDEF_INSTRUCTION from user space
-
- p = get_kprobe_by_insn_slot(addr, tgid, regs);
- if (!p) {
- /* Not one of ours: let kernel handle it */
- DBPRINTF ("no_kprobe");
- goto no_kprobe;
- }
- retprobe = 1;
- DBPRINTF ("uretprobe %p\n", addr);
- } else {
- /* Not one of ours: let kernel handle it */
- DBPRINTF ("no_kprobe");
- goto no_kprobe;
- }
- }
- // restore opcode for thumb app
- if (user_mode( regs ) && thumb_mode( regs )) {
- if (!isThumb2(p->opcode)) {
- unsigned long tmp = p->opcode >> 16;
- write_proc_vm_atomic(current, (unsigned long)((unsigned short*)p->addr + 1), &tmp, 2);
-
- // "2*sizeof(kprobe_opcode_t)" - strange. Should be "sizeof(kprobe_opcode_t)", need to test
- flush_icache_range((unsigned int) p->addr, ((unsigned int)p->addr) + (2 * sizeof(kprobe_opcode_t)));
- }
+ /* Not one of ours: let kernel handle it */
+ DBPRINTF ("no_kprobe");
+ goto no_kprobe;
}
+
set_current_kprobe(p, NULL, NULL);
if(!reenter)
kcb->kprobe_status = KPROBE_HIT_ACTIVE;
err_out = 1; // return with death
goto out;
-no_kprobe_live:
- msg_out = "no_kprobe live\n";
- err_out = 0; // ok - life is life
- goto out;
-
out:
preempt_enable_no_resched();
#ifdef OVERHEAD_DEBUG
local_irq_restore(flags);
return ret;
}
-EXPORT_SYMBOL_GPL(kprobe_trap_handler);
int setjmp_pre_handler (struct kprobe *p, struct pt_regs *regs)
{
return 1;
}
+EXPORT_SYMBOL_GPL(trampoline_probe_handler);
void __arch_prepare_kretprobe (struct kretprobe *rp, struct pt_regs *regs)
{
int arch_check_insn_arm(struct arch_specific_insn *ainsn);
int prep_pc_dep_insn_execbuf(kprobe_opcode_t *insns, kprobe_opcode_t insn, int uregs);
void free_insn_slot(struct hlist_head *page_list, struct task_struct *task, kprobe_opcode_t *slot);
-int isThumb2(kprobe_opcode_t insn);
void pc_dep_insn_execbuf(void);
void gen_insn_execbuf(void);
void gen_insn_execbuf_thumb(void);
return (kprobe_opcode_t)((long)addr + 8 + branch_displacement(insn));
}
+/* is instruction Thumb2 and NOT a branch, etc... */
+static int is_thumb2(kprobe_opcode_t insn)
+{
+ return ((insn & 0xf800) == 0xe800 ||
+ (insn & 0xf800) == 0xf000 ||
+ (insn & 0xf800) == 0xf800);
+}
+
static int arch_copy_trampoline_arm_uprobe(struct kprobe *p, struct task_struct *task, int atomic)
{
kprobe_opcode_t insns[UPROBES_TRAMP_LEN];
*((unsigned short*)insns + 13) = 0xdeff;
*((unsigned short*)insns + 14) = addr & 0x0000ffff;
*((unsigned short*)insns + 15) = addr >> 16;
- if (!isThumb2(insn[0])) {
+ if (!is_thumb2(insn[0])) {
addr = ((unsigned int)p->addr) + 2;
*((unsigned short*)insns + 16) = (addr & 0x0000ffff) | 0x1;
*((unsigned short*)insns + 17) = addr >> 16;
} else {
memcpy(insns, gen_insn_execbuf_thumb, 18 * 2);
*((unsigned short*)insns + 13) = 0xdeff;
- if (!isThumb2(insn[0])) {
+ if (!is_thumb2(insn[0])) {
addr = ((unsigned int)p->addr) + 2;
*((unsigned short*)insns + 2) = insn[0];
*((unsigned short*)insns + 16) = (addr & 0x0000ffff) | 0x1;
return ret;
}
+static int check_validity_insn(struct kprobe *p, struct pt_regs *regs, struct task_struct *task)
+{
+ struct kprobe *kp;
+
+ if (unlikely(thumb_mode(regs))) {
+ if (p->safe_thumb != -1) {
+ p->ainsn.insn = p->ainsn.insn_thumb;
+ list_for_each_entry_rcu(kp, &p->list, list) {
+ kp->ainsn.insn = p->ainsn.insn_thumb;
+ }
+ } else {
+ printk("Error in %s at %d: we are in thumb mode (!) and check instruction was fail \
+ (%0lX instruction at %p address)!\n", __FILE__, __LINE__, p->opcode, p->addr);
+ // Test case when we do our actions on already running application
+ arch_disarm_uprobe(p, task);
+ return -1;
+ }
+ } else {
+ if (p->safe_arm != -1) {
+ p->ainsn.insn = p->ainsn.insn_arm;
+ list_for_each_entry_rcu(kp, &p->list, list) {
+ kp->ainsn.insn = p->ainsn.insn_arm;
+ }
+ } else {
+ printk("Error in %s at %d: we are in arm mode (!) and check instruction was fail \
+ (%0lX instruction at %p address)!\n", __FILE__, __LINE__, p->opcode, p->addr);
+ // Test case when we do our actions on already running application
+ arch_disarm_uprobe(p, task);
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+static int uprobe_handler(struct pt_regs *regs)
+{
+ int err_out = 0;
+ char *msg_out = NULL;
+ struct task_struct *task = current;
+ pid_t tgid = task->tgid;
+ kprobe_opcode_t *addr = (kprobe_opcode_t *)(regs->ARM_pc);
+ struct kprobe *p = NULL;
+ int ret = 0, retprobe = 0;
+ struct kprobe_ctlblk *kcb;
+
+#ifdef SUPRESS_BUG_MESSAGES
+ int swap_oops_in_progress;
+ // oops_in_progress used to avoid BUG() messages that slow down kprobe_handler() execution
+ swap_oops_in_progress = oops_in_progress;
+ oops_in_progress = 1;
+#endif
+
+ p = get_kprobe(addr, tgid);
+
+ if (p && (check_validity_insn(p, regs, task) != 0)) {
+ goto no_uprobe_live;
+ }
+
+ /* We're in an interrupt, but this is clear and BUG()-safe. */
+ kcb = get_kprobe_ctlblk();
+
+ if (p == NULL) {
+ p = get_kprobe_by_insn_slot(addr, tgid, regs);
+ if (p == NULL) {
+ /* Not one of ours: let kernel handle it */
+ goto no_uprobe;
+ }
+
+ retprobe = 1;
+ }
+
+ /* restore opcode for thumb app */
+ if (thumb_mode(regs)) {
+ if (!is_thumb2(p->opcode)) {
+ unsigned long tmp = p->opcode >> 16;
+ write_proc_vm_atomic(task, (unsigned long)((unsigned short*)p->addr + 1), &tmp, 2);
+
+ // "2*sizeof(kprobe_opcode_t)" - strange. Should be "sizeof(kprobe_opcode_t)", need to test
+ flush_icache_range((unsigned int)p->addr, ((unsigned int)p->addr) + (2 * sizeof(kprobe_opcode_t)));
+ }
+ }
+
+ set_current_kprobe(p, NULL, NULL);
+ kcb->kprobe_status = KPROBE_HIT_ACTIVE;
+
+ if (retprobe) {
+ ret = trampoline_probe_handler(p, regs);
+ } else if (p->pre_handler) {
+ ret = p->pre_handler(p, regs);
+ if(p->pre_handler != trampoline_probe_handler) {
+ reset_current_kprobe();
+ }
+ }
+
+ if (ret) {
+ /* handler has already set things up, so skip ss setup */
+ err_out = 0;
+ goto out;
+ }
+
+no_uprobe:
+ msg_out = "no_uprobe\n";
+ err_out = 1; // return with death
+ goto out;
+
+no_uprobe_live:
+ msg_out = "no_uprobe live\n";
+ err_out = 0; // ok - life is life
+ goto out;
+
+out:
+#ifdef SUPRESS_BUG_MESSAGES
+ oops_in_progress = swap_oops_in_progress;
+#endif
+
+ if(msg_out) {
+ printk(msg_out);
+ }
+
+ return err_out;
+}
+
+int uprobe_trap_handler(struct pt_regs *regs, unsigned int instr)
+{
+ int ret;
+ unsigned long flags;
+ local_irq_save(flags);
+
+ preempt_disable();
+ ret = uprobe_handler(regs);
+ preempt_enable_no_resched();
+
+ local_irq_restore(flags);
+ return ret;
+}
+
/* userspace probes hook (arm) */
static struct undef_hook undef_hook_for_us_arm = {
.instr_mask = 0xffffffff,
.instr_val = BREAKPOINT_INSTRUCTION,
.cpsr_mask = MODE_MASK,
.cpsr_val = USR_MODE,
- .fn = kprobe_trap_handler
+ .fn = uprobe_trap_handler
};
/* userspace probes hook (thumb) */
.instr_val = BREAKPOINT_INSTRUCTION & 0x0000ffff,
.cpsr_mask = MODE_MASK,
.cpsr_val = USR_MODE,
- .fn = kprobe_trap_handler
+ .fn = uprobe_trap_handler
};
int swap_arch_init_uprobes(void)
projects / kernel / swap-modules.git / commitdiff