include/linux/kprobes.h | 2 - kernel/kprobes.c | 144 +++++++++++++++++++++++------------------------ 2 files changed, 72 insertions(+), 74 deletions(-)
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.
Reported-by: Max Filippov <jcmvbkbc@gmail.com>
Fixes: d741bf41d7c7 ("kprobes: Remove kretprobe hash")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
include/linux/kprobes.h | 2 -
kernel/kprobes.c | 144 +++++++++++++++++++++++------------------------
2 files changed, 72 insertions(+), 74 deletions(-)
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 157168769fc2..55041d2f884d 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -424,7 +424,7 @@ void unregister_kretprobe(struct kretprobe *rp);
int register_kretprobes(struct kretprobe **rps, int num);
void unregister_kretprobes(struct kretprobe **rps, int num);
-#ifdef CONFIG_KRETPROBE_ON_RETHOOK
+#if defined(CONFIG_KRETPROBE_ON_RETHOOK) || !defined(CONFIG_KRETPROBES)
#define kprobe_flush_task(tk) do {} while (0)
#else
void kprobe_flush_task(struct task_struct *tk);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index dd58c0be9ce2..f214f8c088ed 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)
On Tue, May 3, 2022 at 8:36 PM Masami Hiramatsu <mhiramat@kernel.org> wrote:
>
> 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.
>
> Reported-by: Max Filippov <jcmvbkbc@gmail.com>
> Fixes: d741bf41d7c7 ("kprobes: Remove kretprobe hash")
> Cc: stable@vger.kernel.org
> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> ---
> include/linux/kprobes.h | 2 -
> kernel/kprobes.c | 144 +++++++++++++++++++++++------------------------
> 2 files changed, 72 insertions(+), 74 deletions(-)
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
--
Thanks.
-- Max
On Wed, 4 May 2022 10:53:42 -0700
Max Filippov <jcmvbkbc@gmail.com> wrote:
> On Tue, May 3, 2022 at 8:36 PM Masami Hiramatsu <mhiramat@kernel.org> wrote:
> >
> > 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.
> >
> > Reported-by: Max Filippov <jcmvbkbc@gmail.com>
> > Fixes: d741bf41d7c7 ("kprobes: Remove kretprobe hash")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> > ---
> > include/linux/kprobes.h | 2 -
> > kernel/kprobes.c | 144 +++++++++++++++++++++++------------------------
> > 2 files changed, 72 insertions(+), 74 deletions(-)
>
> Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Thank you!
Steve, can you pick this fix?
Thanks,
--
Masami Hiramatsu <mhiramat@kernel.org>
On Thu, 5 May 2022 09:31:40 +0900 Masami Hiramatsu <mhiramat@kernel.org> wrote: > Steve, can you pick this fix? Hi Masami, When I get back home from traveling I'll pull this in. -- Steve
On Sat, 7 May 2022 09:57:23 -0400 Steven Rostedt <rostedt@goodmis.org> wrote: > On Thu, 5 May 2022 09:31:40 +0900 > Masami Hiramatsu <mhiramat@kernel.org> wrote: > > > Steve, can you pick this fix? > > Hi Masami, > > When I get back home from traveling I'll pull this in. > Just added it to my queue. I'll be running tests when I've finished with all the patches in my backlog. -- Steve
Hello Max,
Can you test this patch? Since the other archs already implemented
kretprobe, I couldn't test it without modifying kernel.
Thank you,
On Wed, 4 May 2022 12:36:31 +0900
Masami Hiramatsu <mhiramat@kernel.org> wrote:
> 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.
>
> Reported-by: Max Filippov <jcmvbkbc@gmail.com>
> Fixes: d741bf41d7c7 ("kprobes: Remove kretprobe hash")
> Cc: stable@vger.kernel.org
> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> ---
> include/linux/kprobes.h | 2 -
> kernel/kprobes.c | 144 +++++++++++++++++++++++------------------------
> 2 files changed, 72 insertions(+), 74 deletions(-)
>
> diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
> index 157168769fc2..55041d2f884d 100644
> --- a/include/linux/kprobes.h
> +++ b/include/linux/kprobes.h
> @@ -424,7 +424,7 @@ void unregister_kretprobe(struct kretprobe *rp);
> int register_kretprobes(struct kretprobe **rps, int num);
> void unregister_kretprobes(struct kretprobe **rps, int num);
>
> -#ifdef CONFIG_KRETPROBE_ON_RETHOOK
> +#if defined(CONFIG_KRETPROBE_ON_RETHOOK) || !defined(CONFIG_KRETPROBES)
> #define kprobe_flush_task(tk) do {} while (0)
> #else
> void kprobe_flush_task(struct task_struct *tk);
> diff --git a/kernel/kprobes.c b/kernel/kprobes.c
> index dd58c0be9ce2..f214f8c088ed 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)
>
--
Masami Hiramatsu <mhiramat@kernel.org>
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