Re: [PATCH 13/23] bpf: rework the compat kernel probe handling

Andrii Nakryiko
2020-05-21T22:10:56Z

On Thu, May 21, 2020 at 8:26 AM Christoph Hellwig <hch@lst.de> wrote:
>
> Instead of using the dangerous probe_kernel_read and strncpy_from_unsafe
> helpers, rework the compat probes to check if an address is a kernel or
> userspace one, and then use the low-level kernel or user probe helper
> shared by the proper kernel and user probe helpers. This slightly
> changes behavior as the compat probe on a user address doesn't check
> the lockdown flags, just as the pure user probes do.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---

Looks good, thanks.

Acked-by: Andrii Nakryiko <andriin@fb.com>

> kernel/trace/bpf_trace.c | 109 ++++++++++++++++++++++++---------------
> 1 file changed, 67 insertions(+), 42 deletions(-)
> …