diff mbox series

[bpf-next,v4,1/2] bpf: implement bpf_send_signal_task() kfunc

Message ID 20241008114940.44305-2-puranjay@kernel.org (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series Implement mechanism to signal other threads | expand

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Commit Message

Puranjay Mohan Oct. 8, 2024, 11:49 a.m. UTC 
Implement bpf_send_signal_task kfunc that is similar to
bpf_send_signal_thread and bpf_send_signal helpers  but can be used to
send signals to other threads and processes. It also supports sending a
cookie with the signal similar to sigqueue().

If the receiving process establishes a handler for the signal using the
SA_SIGINFO flag to sigaction(), then it can obtain this cookie via the
si_value field of the siginfo_t structure passed as the second argument
to the handler.

Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
---
 kernel/bpf/helpers.c     |  1 +
 kernel/trace/bpf_trace.c | 52 +++++++++++++++++++++++++++++++++-------
 2 files changed, 45 insertions(+), 8 deletions(-)

Comments

Andrii Nakryiko Oct. 8, 2024, 6:19 p.m. UTC | #1 
On Tue, Oct 8, 2024 at 4:49 AM Puranjay Mohan <puranjay@kernel.org> wrote:
>
> Implement bpf_send_signal_task kfunc that is similar to
> bpf_send_signal_thread and bpf_send_signal helpers  but can be used to
> send signals to other threads and processes. It also supports sending a
> cookie with the signal similar to sigqueue().
>
> If the receiving process establishes a handler for the signal using the
> SA_SIGINFO flag to sigaction(), then it can obtain this cookie via the
> si_value field of the siginfo_t structure passed as the second argument
> to the handler.
>
> Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
> ---
>  kernel/bpf/helpers.c     |  1 +
>  kernel/trace/bpf_trace.c | 52 +++++++++++++++++++++++++++++++++-------
>  2 files changed, 45 insertions(+), 8 deletions(-)
>
> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
> index 4053f279ed4cc..2fd3feefb9d94 100644
> --- a/kernel/bpf/helpers.c
> +++ b/kernel/bpf/helpers.c
> @@ -3035,6 +3035,7 @@ BTF_ID_FLAGS(func, bpf_task_get_cgroup1, KF_ACQUIRE | KF_RCU | KF_RET_NULL)
>  #endif
>  BTF_ID_FLAGS(func, bpf_task_from_pid, KF_ACQUIRE | KF_RET_NULL)
>  BTF_ID_FLAGS(func, bpf_throw)
> +BTF_ID_FLAGS(func, bpf_send_signal_task, KF_TRUSTED_ARGS)
>  BTF_KFUNCS_END(generic_btf_ids)
>
>  static const struct btf_kfunc_id_set generic_kfunc_set = {
> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
> index a582cd25ca876..d9662e84510d3 100644
> --- a/kernel/trace/bpf_trace.c
> +++ b/kernel/trace/bpf_trace.c
> @@ -802,6 +802,8 @@ struct send_signal_irq_work {
>         struct task_struct *task;
>         u32 sig;
>         enum pid_type type;
> +       bool has_siginfo;
> +       struct kernel_siginfo info;
>  };
>
>  static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
> @@ -809,27 +811,46 @@ static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
>  static void do_bpf_send_signal(struct irq_work *entry)
>  {
>         struct send_signal_irq_work *work;
> +       struct kernel_siginfo *siginfo;
>
>         work = container_of(entry, struct send_signal_irq_work, irq_work);
> -       group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
> +       siginfo = work->has_siginfo ? &work->info : SEND_SIG_PRIV;
> +
> +       group_send_sig_info(work->sig, siginfo, work->task, work->type);
>         put_task_struct(work->task);
>  }
>
> -static int bpf_send_signal_common(u32 sig, enum pid_type type)
> +static int bpf_send_signal_common(u32 sig, enum pid_type type, struct task_struct *task, u64 value)
>  {
>         struct send_signal_irq_work *work = NULL;
> +       struct kernel_siginfo info;
> +       struct kernel_siginfo *siginfo;
> +
> +       if (!task) {
> +               task = current;
> +               siginfo = SEND_SIG_PRIV;
> +       } else {
> +               clear_siginfo(&info);
> +               info.si_signo = sig;
> +               info.si_errno = 0;
> +               info.si_code = SI_KERNEL;
> +               info.si_pid = 0;
> +               info.si_uid = 0;
> +               info.si_value.sival_ptr = (void *)(unsigned long)value;
> +               siginfo = &info;
> +       }
>
>         /* Similar to bpf_probe_write_user, task needs to be
>          * in a sound condition and kernel memory access be
>          * permitted in order to send signal to the current
>          * task.
>          */
> -       if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
> +       if (unlikely(task->flags & (PF_KTHREAD | PF_EXITING)))
>                 return -EPERM;
>         if (unlikely(!nmi_uaccess_okay()))
>                 return -EPERM;
>         /* Task should not be pid=1 to avoid kernel panic. */
> -       if (unlikely(is_global_init(current)))
> +       if (unlikely(is_global_init(task)))
>                 return -EPERM;
>
>         if (irqs_disabled()) {
> @@ -847,19 +868,21 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type)
>                  * to the irq_work. The current task may change when queued
>                  * irq works get executed.
>                  */
> -               work->task = get_task_struct(current);
> +               work->task = get_task_struct(task);
> +               work->has_siginfo = siginfo == &info;
> +               copy_siginfo(&work->info, &info);

we shouldn't copy_siginfo() if !work->has_siginfo, no?

other than that, lgtm

Acked-by: Andrii Nakryiko <andrii@kernel.org>

>                 work->sig = sig;
>                 work->type = type;
>                 irq_work_queue(&work->irq_work);
>                 return 0;
>         }
>
> -       return group_send_sig_info(sig, SEND_SIG_PRIV, current, type);
> +       return group_send_sig_info(sig, siginfo, task, type);
>  }
>
>  BPF_CALL_1(bpf_send_signal, u32, sig)
>  {
> -       return bpf_send_signal_common(sig, PIDTYPE_TGID);
> +       return bpf_send_signal_common(sig, PIDTYPE_TGID, NULL, 0);
>  }
>
>  static const struct bpf_func_proto bpf_send_signal_proto = {
> @@ -871,7 +894,7 @@ static const struct bpf_func_proto bpf_send_signal_proto = {
>
>  BPF_CALL_1(bpf_send_signal_thread, u32, sig)
>  {
> -       return bpf_send_signal_common(sig, PIDTYPE_PID);
> +       return bpf_send_signal_common(sig, PIDTYPE_PID, NULL, 0);
>  }
>
>  static const struct bpf_func_proto bpf_send_signal_thread_proto = {
> @@ -3484,3 +3507,16 @@ static int __init bpf_kprobe_multi_kfuncs_init(void)
>  }
>
>  late_initcall(bpf_kprobe_multi_kfuncs_init);
> +
> +__bpf_kfunc_start_defs();
> +
> +__bpf_kfunc int bpf_send_signal_task(struct task_struct *task, int sig, enum pid_type type,
> +                                    u64 value)
> +{
> +       if (type != PIDTYPE_PID && type != PIDTYPE_TGID)
> +               return -EINVAL;
> +
> +       return bpf_send_signal_common(sig, type, task, value);
> +}
> +
> +__bpf_kfunc_end_defs();
> --
> 2.40.1
>
Puranjay Mohan Oct. 15, 2024, 9:56 a.m. UTC | #2 
Andrii Nakryiko <andrii.nakryiko@gmail.com> writes:

> On Tue, Oct 8, 2024 at 4:49 AM Puranjay Mohan <puranjay@kernel.org> wrote:
>>
>> Implement bpf_send_signal_task kfunc that is similar to
>> bpf_send_signal_thread and bpf_send_signal helpers  but can be used to
>> send signals to other threads and processes. It also supports sending a
>> cookie with the signal similar to sigqueue().
>>
>> If the receiving process establishes a handler for the signal using the
>> SA_SIGINFO flag to sigaction(), then it can obtain this cookie via the
>> si_value field of the siginfo_t structure passed as the second argument
>> to the handler.
>>
>> Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
>> ---
>>  kernel/bpf/helpers.c     |  1 +
>>  kernel/trace/bpf_trace.c | 52 +++++++++++++++++++++++++++++++++-------
>>  2 files changed, 45 insertions(+), 8 deletions(-)
>>
>> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
>> index 4053f279ed4cc..2fd3feefb9d94 100644
>> --- a/kernel/bpf/helpers.c
>> +++ b/kernel/bpf/helpers.c
>> @@ -3035,6 +3035,7 @@ BTF_ID_FLAGS(func, bpf_task_get_cgroup1, KF_ACQUIRE | KF_RCU | KF_RET_NULL)
>>  #endif
>>  BTF_ID_FLAGS(func, bpf_task_from_pid, KF_ACQUIRE | KF_RET_NULL)
>>  BTF_ID_FLAGS(func, bpf_throw)
>> +BTF_ID_FLAGS(func, bpf_send_signal_task, KF_TRUSTED_ARGS)
>>  BTF_KFUNCS_END(generic_btf_ids)
>>
>>  static const struct btf_kfunc_id_set generic_kfunc_set = {
>> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
>> index a582cd25ca876..d9662e84510d3 100644
>> --- a/kernel/trace/bpf_trace.c
>> +++ b/kernel/trace/bpf_trace.c
>> @@ -802,6 +802,8 @@ struct send_signal_irq_work {
>>         struct task_struct *task;
>>         u32 sig;
>>         enum pid_type type;
>> +       bool has_siginfo;
>> +       struct kernel_siginfo info;
>>  };
>>
>>  static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
>> @@ -809,27 +811,46 @@ static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
>>  static void do_bpf_send_signal(struct irq_work *entry)
>>  {
>>         struct send_signal_irq_work *work;
>> +       struct kernel_siginfo *siginfo;
>>
>>         work = container_of(entry, struct send_signal_irq_work, irq_work);
>> -       group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
>> +       siginfo = work->has_siginfo ? &work->info : SEND_SIG_PRIV;
>> +
>> +       group_send_sig_info(work->sig, siginfo, work->task, work->type);
>>         put_task_struct(work->task);
>>  }
>>
>> -static int bpf_send_signal_common(u32 sig, enum pid_type type)
>> +static int bpf_send_signal_common(u32 sig, enum pid_type type, struct task_struct *task, u64 value)
>>  {
>>         struct send_signal_irq_work *work = NULL;
>> +       struct kernel_siginfo info;
>> +       struct kernel_siginfo *siginfo;
>> +
>> +       if (!task) {
>> +               task = current;
>> +               siginfo = SEND_SIG_PRIV;
>> +       } else {
>> +               clear_siginfo(&info);
>> +               info.si_signo = sig;
>> +               info.si_errno = 0;
>> +               info.si_code = SI_KERNEL;
>> +               info.si_pid = 0;
>> +               info.si_uid = 0;
>> +               info.si_value.sival_ptr = (void *)(unsigned long)value;
>> +               siginfo = &info;
>> +       }
>>
>>         /* Similar to bpf_probe_write_user, task needs to be
>>          * in a sound condition and kernel memory access be
>>          * permitted in order to send signal to the current
>>          * task.
>>          */
>> -       if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
>> +       if (unlikely(task->flags & (PF_KTHREAD | PF_EXITING)))
>>                 return -EPERM;
>>         if (unlikely(!nmi_uaccess_okay()))
>>                 return -EPERM;
>>         /* Task should not be pid=1 to avoid kernel panic. */
>> -       if (unlikely(is_global_init(current)))
>> +       if (unlikely(is_global_init(task)))
>>                 return -EPERM;
>>
>>         if (irqs_disabled()) {
>> @@ -847,19 +868,21 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type)
>>                  * to the irq_work. The current task may change when queued
>>                  * irq works get executed.
>>                  */
>> -               work->task = get_task_struct(current);
>> +               work->task = get_task_struct(task);
>> +               work->has_siginfo = siginfo == &info;
>> +               copy_siginfo(&work->info, &info);
>
> we shouldn't copy_siginfo() if !work->has_siginfo, no?

Yes, but it is only used when has_siginfo is true, so copying it doesn't
cause any problems. I just didn't want to add another check here.

> other than that, lgtm
>
> Acked-by: Andrii Nakryiko <andrii@kernel.org>

Thanks for the Ack. I hope this can go in now!

Thanks,
Puranjay Mohan
Alexei Starovoitov Oct. 15, 2024, 6:20 p.m. UTC | #3 
On Tue, Oct 15, 2024 at 2:57 AM Puranjay Mohan <puranjay@kernel.org> wrote:
>
> Andrii Nakryiko <andrii.nakryiko@gmail.com> writes:
>
> > On Tue, Oct 8, 2024 at 4:49 AM Puranjay Mohan <puranjay@kernel.org> wrote:
> >>
> >> Implement bpf_send_signal_task kfunc that is similar to
> >> bpf_send_signal_thread and bpf_send_signal helpers  but can be used to
> >> send signals to other threads and processes. It also supports sending a
> >> cookie with the signal similar to sigqueue().
> >>
> >> If the receiving process establishes a handler for the signal using the
> >> SA_SIGINFO flag to sigaction(), then it can obtain this cookie via the
> >> si_value field of the siginfo_t structure passed as the second argument
> >> to the handler.
> >>
> >> Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
> >> ---
> >>  kernel/bpf/helpers.c     |  1 +
> >>  kernel/trace/bpf_trace.c | 52 +++++++++++++++++++++++++++++++++-------
> >>  2 files changed, 45 insertions(+), 8 deletions(-)
> >>
> >> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
> >> index 4053f279ed4cc..2fd3feefb9d94 100644
> >> --- a/kernel/bpf/helpers.c
> >> +++ b/kernel/bpf/helpers.c
> >> @@ -3035,6 +3035,7 @@ BTF_ID_FLAGS(func, bpf_task_get_cgroup1, KF_ACQUIRE | KF_RCU | KF_RET_NULL)
> >>  #endif
> >>  BTF_ID_FLAGS(func, bpf_task_from_pid, KF_ACQUIRE | KF_RET_NULL)
> >>  BTF_ID_FLAGS(func, bpf_throw)
> >> +BTF_ID_FLAGS(func, bpf_send_signal_task, KF_TRUSTED_ARGS)
> >>  BTF_KFUNCS_END(generic_btf_ids)
> >>
> >>  static const struct btf_kfunc_id_set generic_kfunc_set = {
> >> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
> >> index a582cd25ca876..d9662e84510d3 100644
> >> --- a/kernel/trace/bpf_trace.c
> >> +++ b/kernel/trace/bpf_trace.c
> >> @@ -802,6 +802,8 @@ struct send_signal_irq_work {
> >>         struct task_struct *task;
> >>         u32 sig;
> >>         enum pid_type type;
> >> +       bool has_siginfo;
> >> +       struct kernel_siginfo info;
> >>  };
> >>
> >>  static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
> >> @@ -809,27 +811,46 @@ static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
> >>  static void do_bpf_send_signal(struct irq_work *entry)
> >>  {
> >>         struct send_signal_irq_work *work;
> >> +       struct kernel_siginfo *siginfo;
> >>
> >>         work = container_of(entry, struct send_signal_irq_work, irq_work);
> >> -       group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
> >> +       siginfo = work->has_siginfo ? &work->info : SEND_SIG_PRIV;
> >> +
> >> +       group_send_sig_info(work->sig, siginfo, work->task, work->type);
> >>         put_task_struct(work->task);
> >>  }
> >>
> >> -static int bpf_send_signal_common(u32 sig, enum pid_type type)
> >> +static int bpf_send_signal_common(u32 sig, enum pid_type type, struct task_struct *task, u64 value)
> >>  {
> >>         struct send_signal_irq_work *work = NULL;
> >> +       struct kernel_siginfo info;
> >> +       struct kernel_siginfo *siginfo;
> >> +
> >> +       if (!task) {
> >> +               task = current;
> >> +               siginfo = SEND_SIG_PRIV;
> >> +       } else {
> >> +               clear_siginfo(&info);
> >> +               info.si_signo = sig;
> >> +               info.si_errno = 0;
> >> +               info.si_code = SI_KERNEL;
> >> +               info.si_pid = 0;
> >> +               info.si_uid = 0;
> >> +               info.si_value.sival_ptr = (void *)(unsigned long)value;
> >> +               siginfo = &info;
> >> +       }
> >>
> >>         /* Similar to bpf_probe_write_user, task needs to be
> >>          * in a sound condition and kernel memory access be
> >>          * permitted in order to send signal to the current
> >>          * task.
> >>          */
> >> -       if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
> >> +       if (unlikely(task->flags & (PF_KTHREAD | PF_EXITING)))
> >>                 return -EPERM;
> >>         if (unlikely(!nmi_uaccess_okay()))
> >>                 return -EPERM;
> >>         /* Task should not be pid=1 to avoid kernel panic. */
> >> -       if (unlikely(is_global_init(current)))
> >> +       if (unlikely(is_global_init(task)))
> >>                 return -EPERM;
> >>
> >>         if (irqs_disabled()) {
> >> @@ -847,19 +868,21 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type)
> >>                  * to the irq_work. The current task may change when queued
> >>                  * irq works get executed.
> >>                  */
> >> -               work->task = get_task_struct(current);
> >> +               work->task = get_task_struct(task);
> >> +               work->has_siginfo = siginfo == &info;
> >> +               copy_siginfo(&work->info, &info);
> >
> > we shouldn't copy_siginfo() if !work->has_siginfo, no?
>
> Yes, but it is only used when has_siginfo is true, so copying it doesn't
> cause any problems. I just didn't want to add another check here.

Still, let's avoid a pointless copy.
If I'm reading it correctly it will copy uninitialized memory
and sanitizers won't be happy.

Pls respin.
diff mbox series

Patch

diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 4053f279ed4cc..2fd3feefb9d94 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -3035,6 +3035,7 @@  BTF_ID_FLAGS(func, bpf_task_get_cgroup1, KF_ACQUIRE | KF_RCU | KF_RET_NULL)
 #endif
 BTF_ID_FLAGS(func, bpf_task_from_pid, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_throw)
+BTF_ID_FLAGS(func, bpf_send_signal_task, KF_TRUSTED_ARGS)
 BTF_KFUNCS_END(generic_btf_ids)
 
 static const struct btf_kfunc_id_set generic_kfunc_set = {
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index a582cd25ca876..d9662e84510d3 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -802,6 +802,8 @@  struct send_signal_irq_work {
 	struct task_struct *task;
 	u32 sig;
 	enum pid_type type;
+	bool has_siginfo;
+	struct kernel_siginfo info;
 };
 
 static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
@@ -809,27 +811,46 @@  static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
 static void do_bpf_send_signal(struct irq_work *entry)
 {
 	struct send_signal_irq_work *work;
+	struct kernel_siginfo *siginfo;
 
 	work = container_of(entry, struct send_signal_irq_work, irq_work);
-	group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
+	siginfo = work->has_siginfo ? &work->info : SEND_SIG_PRIV;
+
+	group_send_sig_info(work->sig, siginfo, work->task, work->type);
 	put_task_struct(work->task);
 }
 
-static int bpf_send_signal_common(u32 sig, enum pid_type type)
+static int bpf_send_signal_common(u32 sig, enum pid_type type, struct task_struct *task, u64 value)
 {
 	struct send_signal_irq_work *work = NULL;
+	struct kernel_siginfo info;
+	struct kernel_siginfo *siginfo;
+
+	if (!task) {
+		task = current;
+		siginfo = SEND_SIG_PRIV;
+	} else {
+		clear_siginfo(&info);
+		info.si_signo = sig;
+		info.si_errno = 0;
+		info.si_code = SI_KERNEL;
+		info.si_pid = 0;
+		info.si_uid = 0;
+		info.si_value.sival_ptr = (void *)(unsigned long)value;
+		siginfo = &info;
+	}
 
 	/* Similar to bpf_probe_write_user, task needs to be
 	 * in a sound condition and kernel memory access be
 	 * permitted in order to send signal to the current
 	 * task.
 	 */
-	if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
+	if (unlikely(task->flags & (PF_KTHREAD | PF_EXITING)))
 		return -EPERM;
 	if (unlikely(!nmi_uaccess_okay()))
 		return -EPERM;
 	/* Task should not be pid=1 to avoid kernel panic. */
-	if (unlikely(is_global_init(current)))
+	if (unlikely(is_global_init(task)))
 		return -EPERM;
 
 	if (irqs_disabled()) {
@@ -847,19 +868,21 @@  static int bpf_send_signal_common(u32 sig, enum pid_type type)
 		 * to the irq_work. The current task may change when queued
 		 * irq works get executed.
 		 */
-		work->task = get_task_struct(current);
+		work->task = get_task_struct(task);
+		work->has_siginfo = siginfo == &info;
+		copy_siginfo(&work->info, &info);
 		work->sig = sig;
 		work->type = type;
 		irq_work_queue(&work->irq_work);
 		return 0;
 	}
 
-	return group_send_sig_info(sig, SEND_SIG_PRIV, current, type);
+	return group_send_sig_info(sig, siginfo, task, type);
 }
 
 BPF_CALL_1(bpf_send_signal, u32, sig)
 {
-	return bpf_send_signal_common(sig, PIDTYPE_TGID);
+	return bpf_send_signal_common(sig, PIDTYPE_TGID, NULL, 0);
 }
 
 static const struct bpf_func_proto bpf_send_signal_proto = {
@@ -871,7 +894,7 @@  static const struct bpf_func_proto bpf_send_signal_proto = {
 
 BPF_CALL_1(bpf_send_signal_thread, u32, sig)
 {
-	return bpf_send_signal_common(sig, PIDTYPE_PID);
+	return bpf_send_signal_common(sig, PIDTYPE_PID, NULL, 0);
 }
 
 static const struct bpf_func_proto bpf_send_signal_thread_proto = {
@@ -3484,3 +3507,16 @@  static int __init bpf_kprobe_multi_kfuncs_init(void)
 }
 
 late_initcall(bpf_kprobe_multi_kfuncs_init);
+
+__bpf_kfunc_start_defs();
+
+__bpf_kfunc int bpf_send_signal_task(struct task_struct *task, int sig, enum pid_type type,
+				     u64 value)
+{
+	if (type != PIDTYPE_PID && type != PIDTYPE_TGID)
+		return -EINVAL;
+
+	return bpf_send_signal_common(sig, type, task, value);
+}
+
+__bpf_kfunc_end_defs();