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authorMasami Hiramatsu <mhiramat@kernel.org>2022-05-04 12:36:31 +0900
committerSteven Rostedt (Google) <rostedt@goodmis.org>2022-05-26 21:12:59 -0400
commit43994049180704fd1faf78623fabd9a5cd443708 (patch)
tree0aa8dc0c3179554c04c77bf2759e9cb4f97ca922 /kernel/kprobes.c
parentb27f266f74fbda4ee36c2b2b04d15992860cf23b (diff)
kprobes: Fix build errors with CONFIG_KRETPROBES=n
Max Filippov reported: When building kernel with CONFIG_KRETPROBES=n kernel/kprobes.c compilation fails with the following messages: kernel/kprobes.c: In function ‘recycle_rp_inst’: kernel/kprobes.c:1273:32: error: implicit declaration of function ‘get_kretprobe’ kernel/kprobes.c: In function ‘kprobe_flush_task’: kernel/kprobes.c:1299:35: error: ‘struct task_struct’ has no member named ‘kretprobe_instances’ This came from the commit d741bf41d7c7 ("kprobes: Remove kretprobe hash") which introduced get_kretprobe() and kretprobe_instances member in task_struct when CONFIG_KRETPROBES=y, but did not make recycle_rp_inst() and kprobe_flush_task() depending on CONFIG_KRETPORBES. Since those functions are only used for kretprobe, move those functions into #ifdef CONFIG_KRETPROBE area. Link: https://lkml.kernel.org/r/165163539094.74407.3838114721073251225.stgit@devnote2 Reported-by: Max Filippov <jcmvbkbc@gmail.com> Fixes: d741bf41d7c7 ("kprobes: Remove kretprobe hash") Cc: "Naveen N . Rao" <naveen.n.rao@linux.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: "David S . Miller" <davem@davemloft.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/kprobes.c')
-rw-r--r--kernel/kprobes.c144
1 files changed, 71 insertions, 73 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index dbe57df2e199..172ba75a4a49 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1257,79 +1257,6 @@ void kprobe_busy_end(void)
preempt_enable();
}
-#if !defined(CONFIG_KRETPROBE_ON_RETHOOK)
-static void free_rp_inst_rcu(struct rcu_head *head)
-{
- struct kretprobe_instance *ri = container_of(head, struct kretprobe_instance, rcu);
-
- if (refcount_dec_and_test(&ri->rph->ref))
- kfree(ri->rph);
- kfree(ri);
-}
-NOKPROBE_SYMBOL(free_rp_inst_rcu);
-
-static void recycle_rp_inst(struct kretprobe_instance *ri)
-{
- struct kretprobe *rp = get_kretprobe(ri);
-
- if (likely(rp))
- freelist_add(&ri->freelist, &rp->freelist);
- else
- call_rcu(&ri->rcu, free_rp_inst_rcu);
-}
-NOKPROBE_SYMBOL(recycle_rp_inst);
-
-/*
- * This function is called from delayed_put_task_struct() when a task is
- * dead and cleaned up to recycle any kretprobe instances associated with
- * this task. These left over instances represent probed functions that
- * have been called but will never return.
- */
-void kprobe_flush_task(struct task_struct *tk)
-{
- struct kretprobe_instance *ri;
- struct llist_node *node;
-
- /* Early boot, not yet initialized. */
- if (unlikely(!kprobes_initialized))
- return;
-
- kprobe_busy_begin();
-
- node = __llist_del_all(&tk->kretprobe_instances);
- while (node) {
- ri = container_of(node, struct kretprobe_instance, llist);
- node = node->next;
-
- recycle_rp_inst(ri);
- }
-
- kprobe_busy_end();
-}
-NOKPROBE_SYMBOL(kprobe_flush_task);
-
-static inline void free_rp_inst(struct kretprobe *rp)
-{
- struct kretprobe_instance *ri;
- struct freelist_node *node;
- int count = 0;
-
- 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;
- }
-}
-#endif /* !CONFIG_KRETPROBE_ON_RETHOOK */
-
/* Add the new probe to 'ap->list'. */
static int add_new_kprobe(struct kprobe *ap, struct kprobe *p)
{
@@ -1928,6 +1855,77 @@ static struct notifier_block kprobe_exceptions_nb = {
#ifdef CONFIG_KRETPROBES
#if !defined(CONFIG_KRETPROBE_ON_RETHOOK)
+static void free_rp_inst_rcu(struct rcu_head *head)
+{
+ struct kretprobe_instance *ri = container_of(head, struct kretprobe_instance, rcu);
+
+ if (refcount_dec_and_test(&ri->rph->ref))
+ kfree(ri->rph);
+ kfree(ri);
+}
+NOKPROBE_SYMBOL(free_rp_inst_rcu);
+
+static void recycle_rp_inst(struct kretprobe_instance *ri)
+{
+ struct kretprobe *rp = get_kretprobe(ri);
+
+ if (likely(rp))
+ freelist_add(&ri->freelist, &rp->freelist);
+ else
+ call_rcu(&ri->rcu, free_rp_inst_rcu);
+}
+NOKPROBE_SYMBOL(recycle_rp_inst);
+
+/*
+ * This function is called from delayed_put_task_struct() when a task is
+ * dead and cleaned up to recycle any kretprobe instances associated with
+ * this task. These left over instances represent probed functions that
+ * have been called but will never return.
+ */
+void kprobe_flush_task(struct task_struct *tk)
+{
+ struct kretprobe_instance *ri;
+ struct llist_node *node;
+
+ /* Early boot, not yet initialized. */
+ if (unlikely(!kprobes_initialized))
+ return;
+
+ kprobe_busy_begin();
+
+ node = __llist_del_all(&tk->kretprobe_instances);
+ while (node) {
+ ri = container_of(node, struct kretprobe_instance, llist);
+ node = node->next;
+
+ recycle_rp_inst(ri);
+ }
+
+ kprobe_busy_end();
+}
+NOKPROBE_SYMBOL(kprobe_flush_task);
+
+static inline void free_rp_inst(struct kretprobe *rp)
+{
+ struct kretprobe_instance *ri;
+ struct freelist_node *node;
+ int count = 0;
+
+ 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;
+ }
+}
+
/* This assumes the 'tsk' is the current task or the is not running. */
static kprobe_opcode_t *__kretprobe_find_ret_addr(struct task_struct *tsk,
struct llist_node **cur)