Re: [BUGFIX PATCH] tracing/kprobes: Fix to check notrace function with correct range

[Steven Rostedt]

On Tue, 21 Aug 2018 22:04:57 +0900
Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:

> Fix within_notrace_func() to check notrace function correctly.
> 
> Since the ftrace_location_range(start, end) function checks
> the range inclusively (start <= ftrace-loc <= end), the end
> address must not include the entry address of next function.
> 
> However, within_notrace_func() uses kallsyms_lookup_size_offset()
> to get the function size and calculate the end address from
> adding the size to the entry address. This means the end address
> is the entry address of the next function.
> 
> In the result, within_notrace_func() fails to find notrace
> function if the next function of the target function is
> ftraced.
> 
> Let's subtract 1 from the end address so that ftrace_location_range()
> can check it correctly.
> 
> Fixes: commit 45408c4f9250 ("tracing: kprobes: Prohibit probing on notrace function")
> Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> Reported-by: Michael Rodin <michael@xxxxxxxxxxxx>
> ---
>

Applied. Thanks Masami! I'll start testing this and send it upstream
when it's finished.

-- Steve