• Borislav Petkov's avatar
    x86/fault: Dump user opcode bytes on fatal faults · ba54d856
    Borislav Petkov authored
    Sometimes it is useful to see which user opcode bytes RIP points to
    when a fault happens: be it to rule out RIP corruption, to dump info
    early during boot, when doing core dumps is impossible due to not having
    a writable filesystem yet.
    
    Sometimes it is useful if debugging an issue and one doesn't have access
    to the executable which caused the fault in order to disassemble it.
    
    That last aspect might have some security implications so
    show_unhandled_signals could be revisited for that or a new config option
    added.
    Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
    Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Josh Poimboeuf <jpoimboe@redhat.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Andy Lutomirski <luto@amacapital.net>
    Link: https://lkml.kernel.org/r/20180417161124.5294-7-bp@alien8.de
    ba54d856
fault.c 37.1 KB