Re: [PATCH 4.19.y] tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols

[Francis Laniel <flaniel@linux.microsoft.com>]

Hi!


Le lundi 27 novembre 2023, 16:44:22 CET Greg KH a écrit :
> On Mon, Nov 27, 2023 at 03:41:31PM +0100, Francis Laniel wrote:
> > Hi!
> > 
> > Le vendredi 24 novembre 2023, 17:17:04 CET Greg KH a écrit :
> > > On Fri, Nov 24, 2023 at 01:24:13PM +0100, Francis Laniel wrote:
> > > > When a kprobe is attached to a function that's name is not unique (is
> > > > static and shares the name with other functions in the kernel), the
> > > > kprobe is attached to the first function it finds. This is a bug as
> > > > the
> > > > function that it is attaching to is not necessarily the one that the
> > > > user wants to attach to.
> > > > 
> > > > Instead of blindly picking a function to attach to what is ambiguous,
> > > > error with EADDRNOTAVAIL to let the user know that this function is
> > > > not
> > > > unique, and that the user must use another unique function with an
> > > > address offset to get to the function they want to attach to.
> > > > 
> > > > Link:
> > > > https://lore.kernel.org/all/20231020104250.9537-2-flaniel@linux.micros
> > > > oft
> > > > .com/
> > > > 
> > > > Cc: stable@vger.kernel.org
> > > > Fixes: 413d37d1eb69 ("tracing: Add kprobe-based event tracer")
> > > > Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
> > > > Signed-off-by: Francis Laniel <flaniel@linux.microsoft.com>
> > > > Link:
> > > > https://lore.kernel.org/lkml/20230819101105.b0c104ae4494a7d1f2eea742@k
> > > > ern
> > > > el.org/ Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> > > > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> > > > (cherry picked from commit b022f0c7e404887a7c5229788fc99eff9f9a80d5)
> > > > ---
> > > > 
> > > >  kernel/trace/trace_kprobe.c | 48
> > > >  +++++++++++++++++++++++++++++++++++++
> > > >  1 file changed, 48 insertions(+)
> > > 
> > > Again, we need a version for 5.4.y as well before we can take this
> > > version.
> > 
> > I sent the 5.4.y patch some times ago, you can find it here:
> > https://lore.kernel.org/stable/20231023113623.36423-2-flaniel@linux.micros
> > oft.com/
> > 
> > With the recent batch I sent, I should have cover all the stable kernels.
> > In case I miss one, please indicate it to me so I can fix this problem and
> > ensure all stable kernels have a corresponding patch.
> 
> I only see the following in my stable mbox right now:
> 
>    1   C Nov 27 Francis Laniel  (4.4K) ┬─>[PATCH 5.10.y] tracing/kprobes:
> Return EADDRNOTAVAIL when func matches several symbols 2 r C Nov 24 Francis
> Laniel  (4.4K) └─>[PATCH 5.10.y] tracing/kprobes: Return EADDRNOTAVAIL when
> func matches several symbols 3   F Nov 24 To Francis Lani (1.5K)   └─>
>    4 r T Nov 27 Francis Laniel  (1.9K)     └─>
>    5   F Nov 27 To Francis Lani (2.0K)       └─>
>   23 r C Nov 24 Francis Laniel  (2.7K) [PATCH 4.19.y] tracing/kprobes:
> Return EADDRNOTAVAIL when func matches several symbols 24 r + Nov 27
> Francis Laniel  (2.0K) └─>
> 
> So could you resend them all just to be sure I have all of the latest
> versions that you wish to have applied?

I normally sent again the patch for version 4.14 to 5.15 (it was already 
present in 6.1 and 6.6).
I tested all of them by building the corresponding kernel with the patch 
applied before sending, so they should not break compilation or testing.

Can you please confirm me you received them?

> thanks,
> 
> greg "drowning in patches" k-h

*throws a buoy at greg k-h*


Best regards.