* [PATCH] tracing/fprobe: Fix to check whether fprobe is registered correctly
@ 2022-10-23 14:19 Masami Hiramatsu (Google)
2022-10-24 7:01 ` Jiri Olsa
` (2 more replies)
0 siblings, 3 replies; 5+ messages in thread
From: Masami Hiramatsu (Google) @ 2022-10-23 14:19 UTC (permalink / raw)
To: LKML; +Cc: Linux Trace Kernel, Masami Hiramatsu, Steven Rostedt, Jiri Olsa
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Since commit ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag
for fprobe") introduced fprobe_kprobe_handler() for fprobe::f_op::func,
unregister_fprobe() fails to unregister the registered if user specifies
FPROBE_FL_KPROBE_SHARED flag.
To check it correctly, it should confirm the fprobe::f_op::func is either
fprobe_handler() or fprobe_kprobe_handler().
Fixes: ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag for fprobe")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
kernel/trace/fprobe.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index aac63ca9c3d1..9000d8ea6274 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -301,7 +301,8 @@ int unregister_fprobe(struct fprobe *fp)
{
int ret;
- if (!fp || fp->ops.func != fprobe_handler)
+ if (!fp || (fp->ops.func != fprobe_handler &&
+ fp->ops.func != fprobe_kprobe_handler))
return -EINVAL;
/*
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] tracing/fprobe: Fix to check whether fprobe is registered correctly
2022-10-23 14:19 [PATCH] tracing/fprobe: Fix to check whether fprobe is registered correctly Masami Hiramatsu (Google)
@ 2022-10-24 7:01 ` Jiri Olsa
2022-10-24 14:22 ` Steven Rostedt
2022-10-26 9:11 ` Masami Hiramatsu
2 siblings, 0 replies; 5+ messages in thread
From: Jiri Olsa @ 2022-10-24 7:01 UTC (permalink / raw)
To: Masami Hiramatsu (Google); +Cc: LKML, Linux Trace Kernel, Steven Rostedt
On Sun, Oct 23, 2022 at 11:19:33PM +0900, Masami Hiramatsu (Google) wrote:
> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
>
> Since commit ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag
> for fprobe") introduced fprobe_kprobe_handler() for fprobe::f_op::func,
> unregister_fprobe() fails to unregister the registered if user specifies
> FPROBE_FL_KPROBE_SHARED flag.
> To check it correctly, it should confirm the fprobe::f_op::func is either
> fprobe_handler() or fprobe_kprobe_handler().
>
> Fixes: ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag for fprobe")
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
jirka
> ---
> kernel/trace/fprobe.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
> index aac63ca9c3d1..9000d8ea6274 100644
> --- a/kernel/trace/fprobe.c
> +++ b/kernel/trace/fprobe.c
> @@ -301,7 +301,8 @@ int unregister_fprobe(struct fprobe *fp)
> {
> int ret;
>
> - if (!fp || fp->ops.func != fprobe_handler)
> + if (!fp || (fp->ops.func != fprobe_handler &&
> + fp->ops.func != fprobe_kprobe_handler))
> return -EINVAL;
>
> /*
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] tracing/fprobe: Fix to check whether fprobe is registered correctly
2022-10-23 14:19 [PATCH] tracing/fprobe: Fix to check whether fprobe is registered correctly Masami Hiramatsu (Google)
2022-10-24 7:01 ` Jiri Olsa
@ 2022-10-24 14:22 ` Steven Rostedt
2022-10-25 14:36 ` Masami Hiramatsu
2022-10-26 9:11 ` Masami Hiramatsu
2 siblings, 1 reply; 5+ messages in thread
From: Steven Rostedt @ 2022-10-24 14:22 UTC (permalink / raw)
To: Masami Hiramatsu (Google); +Cc: LKML, Linux Trace Kernel, Jiri Olsa
On Sun, 23 Oct 2022 23:19:33 +0900
"Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:
> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
>
> Since commit ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag
> for fprobe") introduced fprobe_kprobe_handler() for fprobe::f_op::func,
> unregister_fprobe() fails to unregister the registered if user specifies
> FPROBE_FL_KPROBE_SHARED flag.
> To check it correctly, it should confirm the fprobe::f_op::func is either
> fprobe_handler() or fprobe_kprobe_handler().
>
> Fixes: ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag for fprobe")
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> ---
> kernel/trace/fprobe.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
> index aac63ca9c3d1..9000d8ea6274 100644
> --- a/kernel/trace/fprobe.c
> +++ b/kernel/trace/fprobe.c
> @@ -301,7 +301,8 @@ int unregister_fprobe(struct fprobe *fp)
> {
> int ret;
>
> - if (!fp || fp->ops.func != fprobe_handler)
> + if (!fp || (fp->ops.func != fprobe_handler &&
> + fp->ops.func != fprobe_kprobe_handler))
> return -EINVAL;
>
> /*
Should we make this more paranoid?
if (!fp ||
(fprobe_shared_with_kprobes(fp) && fp->ops.func != fprobe_kprobe_handler) ||
(!fprobe_shared_with_kprobes(fp) && fp->ops.func != fprobe_handler))
Or is that over-kill?
-- Steve
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] tracing/fprobe: Fix to check whether fprobe is registered correctly
2022-10-24 14:22 ` Steven Rostedt
@ 2022-10-25 14:36 ` Masami Hiramatsu
0 siblings, 0 replies; 5+ messages in thread
From: Masami Hiramatsu @ 2022-10-25 14:36 UTC (permalink / raw)
To: Steven Rostedt; +Cc: LKML, Linux Trace Kernel, Jiri Olsa
On Mon, 24 Oct 2022 10:22:30 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:
> On Sun, 23 Oct 2022 23:19:33 +0900
> "Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:
>
> > From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> >
> > Since commit ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag
> > for fprobe") introduced fprobe_kprobe_handler() for fprobe::f_op::func,
> > unregister_fprobe() fails to unregister the registered if user specifies
> > FPROBE_FL_KPROBE_SHARED flag.
> > To check it correctly, it should confirm the fprobe::f_op::func is either
> > fprobe_handler() or fprobe_kprobe_handler().
> >
> > Fixes: ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag for fprobe")
> > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> > ---
> > kernel/trace/fprobe.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
> > index aac63ca9c3d1..9000d8ea6274 100644
> > --- a/kernel/trace/fprobe.c
> > +++ b/kernel/trace/fprobe.c
> > @@ -301,7 +301,8 @@ int unregister_fprobe(struct fprobe *fp)
> > {
> > int ret;
> >
> > - if (!fp || fp->ops.func != fprobe_handler)
> > + if (!fp || (fp->ops.func != fprobe_handler &&
> > + fp->ops.func != fprobe_kprobe_handler))
> > return -EINVAL;
> >
> > /*
>
> Should we make this more paranoid?
>
> if (!fp ||
> (fprobe_shared_with_kprobes(fp) && fp->ops.func != fprobe_kprobe_handler) ||
> (!fprobe_shared_with_kprobes(fp) && fp->ops.func != fprobe_handler))
>
> Or is that over-kill?
Yeah, I think it is over-kill since this is just for a safety check, like
checking NULL in free(). Or, are there any way to check the ftrace_ops is
registered?
Thank you,
>
> -- Steve
--
Masami Hiramatsu (Google) <mhiramat@kernel.org>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] tracing/fprobe: Fix to check whether fprobe is registered correctly
2022-10-23 14:19 [PATCH] tracing/fprobe: Fix to check whether fprobe is registered correctly Masami Hiramatsu (Google)
2022-10-24 7:01 ` Jiri Olsa
2022-10-24 14:22 ` Steven Rostedt
@ 2022-10-26 9:11 ` Masami Hiramatsu
2 siblings, 0 replies; 5+ messages in thread
From: Masami Hiramatsu @ 2022-10-26 9:11 UTC (permalink / raw)
To: Masami Hiramatsu (Google)
Cc: LKML, Linux Trace Kernel, Steven Rostedt, Jiri Olsa
On Sun, 23 Oct 2022 23:19:33 +0900
"Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:
> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
>
> Since commit ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag
> for fprobe") introduced fprobe_kprobe_handler() for fprobe::f_op::func,
> unregister_fprobe() fails to unregister the registered if user specifies
> FPROBE_FL_KPROBE_SHARED flag.
> To check it correctly, it should confirm the fprobe::f_op::func is either
> fprobe_handler() or fprobe_kprobe_handler().
>
> Fixes: ab51e15d535e ("fprobe: Introduce FPROBE_FL_KPROBE_SHARED flag for fprobe")
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> ---
> kernel/trace/fprobe.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
> index aac63ca9c3d1..9000d8ea6274 100644
> --- a/kernel/trace/fprobe.c
> +++ b/kernel/trace/fprobe.c
> @@ -301,7 +301,8 @@ int unregister_fprobe(struct fprobe *fp)
> {
> int ret;
>
> - if (!fp || fp->ops.func != fprobe_handler)
> + if (!fp || (fp->ops.func != fprobe_handler &&
> + fp->ops.func != fprobe_kprobe_handler))
Oops, ops.func can be changed by ftrace itself. Hmm, maybe I should check fp->ops.saved_func instead.
Thank you,
> return -EINVAL;
>
> /*
>
--
Masami Hiramatsu (Google) <mhiramat@kernel.org>
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-10-26 9:12 UTC | newest]
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2022-10-23 14:19 [PATCH] tracing/fprobe: Fix to check whether fprobe is registered correctly Masami Hiramatsu (Google)
2022-10-24 7:01 ` Jiri Olsa
2022-10-24 14:22 ` Steven Rostedt
2022-10-25 14:36 ` Masami Hiramatsu
2022-10-26 9:11 ` Masami Hiramatsu
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