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.microsoft .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@kern 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.microsof...
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.
thanks,
greg k-h
Best regards.