On Thu, Feb 06, 2020 at 11:38:30AM +0100, Peter Zijlstra wrote: > On Wed, Feb 05, 2020 at 02:39:47PM -0800, Kristen Carlson Accardi wrote: > > +static long __start___ex_table_addr; > > +static long __stop___ex_table_addr; > > +static long _stext; > > +static long _etext; > > +static long _sinittext; > > +static long _einittext; > > Should you not also adjust __jump_table, __mcount_loc, > __kprobe_blacklist and possibly others that include text addresses? These don't appear to be sorted at build time. AIUI, the problem with ex_table and kallsyms is that they're preprocessed at build time and opaque to the linker's relocation generation. For example, looking at __jump_table, it gets sorted at runtime: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/kernel/jump_label.c#n474 As you're likely aware, we have a number of "special" sections like this, currently collected manually, see *_TEXT: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/kernel/vmlinux.lds.S#n128 I think we can actually add (most of) these to fg-kaslr's awareness (at which point their order will be shuffled respective to other sections, but with their content order unchanged), but it'll require a bit of linker work. I'll mention this series's dependency on the linker's orphaned section handling in another thread... -- Kees Cook
