}
/* Return true if the kprobe is disarmed. Note: p must be on hash list */
-static inline bool kprobe_disarmed(struct kprobe *p)
+bool kprobe_disarmed(struct kprobe *p)
{
struct optimized_kprobe *op;
/* See comment in do_optimize_kprobes() */
lockdep_assert_cpus_held();
- /* Unoptimization must be done anytime */
- if (list_empty(&unoptimizing_list))
- return;
+ if (!list_empty(&unoptimizing_list))
+ arch_unoptimize_kprobes(&unoptimizing_list, &freeing_list);
- arch_unoptimize_kprobes(&unoptimizing_list, &freeing_list);
- /* Loop on 'freeing_list' for disarming */
+ /* Loop on 'freeing_list' for disarming and removing from kprobe hash list */
list_for_each_entry_safe(op, tmp, &freeing_list, list) {
/* Switching from detour code to origin */
op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED;
- /* Disarm probes if marked disabled */
- if (kprobe_disabled(&op->kp))
+ /* Disarm probes if marked disabled and not gone */
+ if (kprobe_disabled(&op->kp) && !kprobe_gone(&op->kp))
arch_disarm_kprobe(&op->kp);
if (kprobe_unused(&op->kp)) {
/*
mutex_unlock(&kprobe_mutex);
}
-static bool optprobe_queued_unopt(struct optimized_kprobe *op)
+bool optprobe_queued_unopt(struct optimized_kprobe *op)
{
struct optimized_kprobe *_op;
op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED;
if (kprobe_unused(p)) {
- /* Enqueue if it is unused */
- list_add(&op->list, &freeing_list);
/*
- * Remove unused probes from the hash list. After waiting
- * for synchronization, this probe is reclaimed.
- * (reclaiming is done by do_free_cleaned_kprobes().)
+ * Unused kprobe is on unoptimizing or freeing list. We move it
+ * to freeing_list and let the kprobe_optimizer() remove it from
+ * the kprobe hash list and free it.
*/
- hlist_del_rcu(&op->kp.hlist);
+ if (optprobe_queued_unopt(op))
+ list_move(&op->list, &freeing_list);
}
/* Don't touch the code, because it is already freed. */
static int __arm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops,
int *cnt)
{
- int ret = 0;
+ int ret;
lockdep_assert_held(&kprobe_mutex);
static int __disarm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops,
int *cnt)
{
- int ret = 0;
+ int ret;
lockdep_assert_held(&kprobe_mutex);
return 0;
}
+static bool is_cfi_preamble_symbol(unsigned long addr)
+{
+ char symbuf[KSYM_NAME_LEN];
+
+ if (lookup_symbol_name(addr, symbuf))
+ return false;
+
+ return str_has_prefix("__cfi_", symbuf) ||
+ str_has_prefix("__pfx_", symbuf);
+}
+
static int check_kprobe_address_safe(struct kprobe *p,
struct module **probed_mod)
{
preempt_disable();
/* Ensure it is not in reserved area nor out of text */
- if (!kernel_text_address((unsigned long) p->addr) ||
+ if (!(core_kernel_text((unsigned long) p->addr) ||
+ is_module_text_address((unsigned long) p->addr)) ||
+ in_gate_area_no_mm((unsigned long) p->addr) ||
within_kprobe_blacklist((unsigned long) p->addr) ||
jump_label_text_reserved(p->addr, p->addr) ||
static_call_text_reserved(p->addr, p->addr) ||
- find_bug((unsigned long)p->addr)) {
+ find_bug((unsigned long)p->addr) ||
+ is_cfi_preamble_symbol((unsigned long)p->addr)) {
ret = -EINVAL;
goto out;
}
struct kprobe *old_p;
struct module *probed_mod;
kprobe_opcode_t *addr;
+ bool on_func_entry;
/* Adjust probe address from symbol */
- addr = kprobe_addr(p);
+ addr = _kprobe_addr(p->addr, p->symbol_name, p->offset, &on_func_entry);
if (IS_ERR(addr))
return PTR_ERR(addr);
p->addr = addr;
mutex_lock(&kprobe_mutex);
+ if (on_func_entry)
+ p->flags |= KPROBE_FLAG_ON_FUNC_ENTRY;
+
old_p = get_kprobe(p->addr);
if (old_p) {
/* Since this may unoptimize 'old_p', locking 'text_mutex'. */
/* Try to disarm and disable this/parent probe */
if (p == orig_p || aggr_kprobe_disabled(orig_p)) {
/*
- * If 'kprobes_all_disarmed' is set, 'orig_p'
- * should have already been disarmed, so
- * skip unneed disarming process.
+ * Don't be lazy here. Even if 'kprobes_all_disarmed'
+ * is false, 'orig_p' might not have been armed yet.
+ * Note arm_all_kprobes() __tries__ to arm all kprobes
+ * on the best effort basis.
*/
- if (!kprobes_all_disarmed) {
+ if (!kprobes_all_disarmed && !kprobe_disabled(orig_p)) {
ret = disarm_kprobe(orig_p, true);
if (ret) {
p->flags &= ~KPROBE_FLAG_DISABLED;
if ((list_p != p) && (list_p->post_handler))
goto noclean;
}
- ap->post_handler = NULL;
+ /*
+ * For the kprobe-on-ftrace case, we keep the
+ * post_handler setting to identify this aggrprobe
+ * armed with kprobe_ipmodify_ops.
+ */
+ if (!kprobe_ftrace(ap))
+ ap->post_handler = NULL;
}
noclean:
/*
#ifdef CONFIG_KRETPROBES
#if !defined(CONFIG_KRETPROBE_ON_RETHOOK)
+
+/* callbacks for objpool of kretprobe instances */
+static int kretprobe_init_inst(void *nod, void *context)
+{
+ struct kretprobe_instance *ri = nod;
+
+ ri->rph = context;
+ return 0;
+}
+static int kretprobe_fini_pool(struct objpool_head *head, void *context)
+{
+ kfree(context);
+ return 0;
+}
+
static void free_rp_inst_rcu(struct rcu_head *head)
{
struct kretprobe_instance *ri = container_of(head, struct kretprobe_instance, rcu);
+ struct kretprobe_holder *rph = ri->rph;
- if (refcount_dec_and_test(&ri->rph->ref))
- kfree(ri->rph);
- kfree(ri);
+ objpool_drop(ri, &rph->pool);
}
NOKPROBE_SYMBOL(free_rp_inst_rcu);
struct kretprobe *rp = get_kretprobe(ri);
if (likely(rp))
- freelist_add(&ri->freelist, &rp->freelist);
+ objpool_push(ri, &rp->rph->pool);
else
call_rcu(&ri->rcu, free_rp_inst_rcu);
}
static inline void free_rp_inst(struct kretprobe *rp)
{
- struct kretprobe_instance *ri;
- struct freelist_node *node;
- int count = 0;
+ struct kretprobe_holder *rph = rp->rph;
- node = rp->freelist.head;
- while (node) {
- ri = container_of(node, struct kretprobe_instance, freelist);
- node = node->next;
-
- kfree(ri);
- count++;
- }
-
- if (refcount_sub_and_test(count, &rp->rph->ref)) {
- kfree(rp->rph);
- rp->rph = NULL;
- }
+ if (!rph)
+ return;
+ rp->rph = NULL;
+ objpool_fini(&rph->pool);
}
/* This assumes the 'tsk' is the current task or the is not running. */
unsigned long kretprobe_find_ret_addr(struct task_struct *tsk, void *fp,
struct llist_node **cur)
{
- struct kretprobe_instance *ri = NULL;
+ struct kretprobe_instance *ri;
kprobe_opcode_t *ret;
if (WARN_ON_ONCE(!cur))
unsigned long __kretprobe_trampoline_handler(struct pt_regs *regs,
void *frame_pointer)
{
- kprobe_opcode_t *correct_ret_addr = NULL;
struct kretprobe_instance *ri = NULL;
struct llist_node *first, *node = NULL;
+ kprobe_opcode_t *correct_ret_addr;
struct kretprobe *rp;
/* Find correct address and all nodes for this frame. */
static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs)
{
struct kretprobe *rp = container_of(p, struct kretprobe, kp);
+ struct kretprobe_holder *rph = rp->rph;
struct kretprobe_instance *ri;
- struct freelist_node *fn;
- fn = freelist_try_get(&rp->freelist);
- if (!fn) {
+ ri = objpool_pop(&rph->pool);
+ if (!ri) {
rp->nmissed++;
return 0;
}
- ri = container_of(fn, struct kretprobe_instance, freelist);
-
if (rp->entry_handler && rp->entry_handler(ri, regs)) {
- freelist_add(&ri->freelist, &rp->freelist);
+ objpool_push(ri, &rph->pool);
return 0;
}
NOKPROBE_SYMBOL(pre_handler_kretprobe);
static void kretprobe_rethook_handler(struct rethook_node *rh, void *data,
+ unsigned long ret_addr,
struct pt_regs *regs)
{
struct kretprobe *rp = (struct kretprobe *)data;
int register_kretprobe(struct kretprobe *rp)
{
int ret;
- struct kretprobe_instance *inst;
int i;
void *addr;
rp->kp.post_handler = NULL;
/* Pre-allocate memory for max kretprobe instances */
- if (rp->maxactive <= 0) {
-#ifdef CONFIG_PREEMPTION
+ if (rp->maxactive <= 0)
rp->maxactive = max_t(unsigned int, 10, 2*num_possible_cpus());
-#else
- rp->maxactive = num_possible_cpus();
-#endif
- }
+
#ifdef CONFIG_KRETPROBE_ON_RETHOOK
- rp->rh = rethook_alloc((void *)rp, kretprobe_rethook_handler);
- if (!rp->rh)
- return -ENOMEM;
+ rp->rh = rethook_alloc((void *)rp, kretprobe_rethook_handler,
+ sizeof(struct kretprobe_instance) +
+ rp->data_size, rp->maxactive);
+ if (IS_ERR(rp->rh))
+ return PTR_ERR(rp->rh);
- for (i = 0; i < rp->maxactive; i++) {
- inst = kzalloc(sizeof(struct kretprobe_instance) +
- rp->data_size, GFP_KERNEL);
- if (inst == NULL) {
- rethook_free(rp->rh);
- rp->rh = NULL;
- return -ENOMEM;
- }
- rethook_add_node(rp->rh, &inst->node);
- }
rp->nmissed = 0;
/* Establish function entry probe point */
ret = register_kprobe(&rp->kp);
rp->rh = NULL;
}
#else /* !CONFIG_KRETPROBE_ON_RETHOOK */
- rp->freelist.head = NULL;
rp->rph = kzalloc(sizeof(struct kretprobe_holder), GFP_KERNEL);
if (!rp->rph)
return -ENOMEM;
- rp->rph->rp = rp;
- for (i = 0; i < rp->maxactive; i++) {
- inst = kzalloc(sizeof(struct kretprobe_instance) +
- rp->data_size, GFP_KERNEL);
- if (inst == NULL) {
- refcount_set(&rp->rph->ref, i);
- free_rp_inst(rp);
- return -ENOMEM;
- }
- inst->rph = rp->rph;
- freelist_add(&inst->freelist, &rp->freelist);
+ if (objpool_init(&rp->rph->pool, rp->maxactive, rp->data_size +
+ sizeof(struct kretprobe_instance), GFP_KERNEL,
+ rp->rph, kretprobe_init_inst, kretprobe_fini_pool)) {
+ kfree(rp->rph);
+ rp->rph = NULL;
+ return -ENOMEM;
}
- refcount_set(&rp->rph->ref, i);
-
+ rcu_assign_pointer(rp->rph->rp, rp);
rp->nmissed = 0;
/* Establish function entry probe point */
ret = register_kprobe(&rp->kp);
#ifdef CONFIG_KRETPROBE_ON_RETHOOK
rethook_free(rps[i]->rh);
#else
- rps[i]->rph->rp = NULL;
+ rcu_assign_pointer(rps[i]->rph->rp, NULL);
#endif
}
mutex_unlock(&kprobe_mutex);
lockdep_assert_held(&kprobe_mutex);
+ /*
+ * The module is going away. We should disarm the kprobe which
+ * is using ftrace, because ftrace framework is still available at
+ * 'MODULE_STATE_GOING' notification.
+ */
+ if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed)
+ disarm_kprobe_ftrace(p);
+
p->flags |= KPROBE_FLAG_GONE;
if (kprobe_aggrprobe(p)) {
/*
* the original probed function (which will be freed soon) any more.
*/
arch_remove_kprobe(p);
-
- /*
- * The module is going away. We should disarm the kprobe which
- * is using ftrace, because ftrace framework is still available at
- * 'MODULE_STATE_GOING' notification.
- */
- if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed)
- disarm_kprobe_ftrace(p);
}
/* Disable one kprobe */
if (!kprobes_all_disarmed && kprobe_disabled(p)) {
p->flags &= ~KPROBE_FLAG_DISABLED;
ret = arm_kprobe(p);
- if (ret)
+ if (ret) {
p->flags |= KPROBE_FLAG_DISABLED;
+ if (p != kp)
+ kp->flags |= KPROBE_FLAG_DISABLED;
+ }
}
out:
mutex_unlock(&kprobe_mutex);
static int __init init_kprobes(void)
{
- int i, err = 0;
+ int i, err;
/* FIXME allocate the probe table, currently defined statically */
/* initialize all list heads */
{
struct hlist_head *head;
struct kprobe *p, *kp;
- const char *sym = NULL;
+ const char *sym;
unsigned int i = *(loff_t *) v;
unsigned long offset = 0;
char *modname, namebuf[KSYM_NAME_LEN];
projects / linux-2.6-microblaze.git / blobdiff