Messages in this thread | | | From | Sami Tolvanen <> | Date | Fri, 1 Oct 2021 13:08:47 -0700 | Subject | Re: [PATCH v4 05/15] tracepoint: Exclude tp_stub_func from CFI checking |
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On Thu, Sep 30, 2021 at 11:51 AM Nick Desaulniers <ndesaulniers@google.com> wrote: > > On Thu, Sep 30, 2021 at 11:05 AM Sami Tolvanen <samitolvanen@google.com> wrote: > > > > If allocate_probes fails, func_remove replaces the old function > > with a pointer to tp_stub_func, which is called using a mismatching > > function pointer that will always trip indirect call checks with > > CONFIG_CFI_CLANG. Use DEFINE_CFI_IMMEDATE_RETURN_STUB to define > > tp_stub_func to allow it to pass CFI checking. > > > > Signed-off-by: Sami Tolvanen <samitolvanen@google.com> > > Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> > > --- > > kernel/tracepoint.c | 5 +---- > > 1 file changed, 1 insertion(+), 4 deletions(-) > > > > diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c > > index 64ea283f2f86..58acc7d86c3f 100644 > > --- a/kernel/tracepoint.c > > +++ b/kernel/tracepoint.c > > looking at 4+5/15 together, I wonder if this TU should explicitly > include linux/cfi.h?
Good point. Currently cfi.h is included in module.h, but including it explicitly makes this less likely to break in future. I'll add an explicit include in v5. Thanks for taking a look!
Sami
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