Re: [lkp-robot] [include/linux/string.h] 6974f0c455: kernel_BUG_at_lib/string.c

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From	Daniel Micay <danielmicay@gmail.com>
Newsgroups	linux.kernel
Subject	Re: [lkp-robot] [include/linux/string.h] 6974f0c455: kernel_BUG_at_lib/string.c
Date	Wed, 26 Jul 2017 04:40:02 +0200
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It was known that there are going to be bugs to work through, many of
them relatively benign like the leaks of data near string constants
(probably other string constants) in rodata. It makes sense to have it
default to WARN with BUG / noreturn as a non-default configuration
option for it, I guess with !COMPILE_TEST like UBSAN_SANITIZE_ALL. I
don't think there's any sane way to bound the length of either reads /
writes. It needs to either WARN + continue on into doing the overflow or
use BUG. Trying to correct it might make things worse and would make
this more complicated / bug-prone. It already has enough subtle edge
cases to deal with.

I think 'benign' is a better term than 'false positive' because there
hasn't been a non-bug found yet. They're mostly not security vulns but
they're undefined behavior.

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Re: [lkp-robot] [include/linux/string.h] 6974f0c455: kernel_BUG_at_lib/string.c Linus Torvalds <torvalds@linux-foundation.org> - 2017-07-20 06:10 +0200
  Re: [lkp-robot] [include/linux/string.h] 6974f0c455:  kernel_BUG_at_lib/string.c Daniel Micay <danielmicay@gmail.com> - 2017-07-20 06:50 +0200
  Re: [lkp-robot] [include/linux/string.h] 6974f0c455:  kernel_BUG_at_lib/string.c Masami Hiramatsu <mhiramat@kernel.org> - 2017-07-20 15:50 +0200
  Re: [lkp-robot] [include/linux/string.h] 6974f0c455:  kernel_BUG_at_lib/string.c Masami Hiramatsu <mhiramat@kernel.org> - 2017-07-20 18:00 +0200
    Re: [lkp-robot] [include/linux/string.h] 6974f0c455: kernel_BUG_at_lib/string.c Linus Torvalds <torvalds@linux-foundation.org> - 2017-07-20 20:50 +0200
      Re: [lkp-robot] [include/linux/string.h] 6974f0c455:  kernel_BUG_at_lib/string.c Masami Hiramatsu <mhiramat@kernel.org> - 2017-07-21 00:30 +0200
      Re: [lkp-robot] [include/linux/string.h] 6974f0c455:  kernel_BUG_at_lib/string.c Masami Hiramatsu <mhiramat@kernel.org> - 2017-07-21 05:40 +0200
  Re: [lkp-robot] [include/linux/string.h] 6974f0c455:  kernel_BUG_at_lib/string.c Ye Xiaolong <xiaolong.ye@intel.com> - 2017-07-21 04:10 +0200
    Re: [lkp-robot] [include/linux/string.h] 6974f0c455: kernel_BUG_at_lib/string.c Kees Cook <keescook@chromium.org> - 2017-07-21 07:50 +0200
    Re: [lkp-robot] [include/linux/string.h] 6974f0c455:  kernel_BUG_at_lib/string.c Andy Shevchenko <andriy.shevchenko@linux.intel.com> - 2017-07-21 11:20 +0200
      Re: [lkp-robot] [include/linux/string.h] 6974f0c455:  kernel_BUG_at_lib/string.c Petr Mladek <pmladek@suse.com> - 2017-07-21 12:10 +0200
  Re: [lkp-robot] [include/linux/string.h] 6974f0c455: kernel_BUG_at_lib/string.c Kees Cook <keescook@chromium.org> - 2017-07-26 01:40 +0200
    Re: [lkp-robot] [include/linux/string.h] 6974f0c455: kernel_BUG_at_lib/string.c Linus Torvalds <torvalds@linux-foundation.org> - 2017-07-26 02:20 +0200
      Re: [lkp-robot] [include/linux/string.h] 6974f0c455: kernel_BUG_at_lib/string.c Kees Cook <keescook@chromium.org> - 2017-07-26 02:40 +0200
        Re: [lkp-robot] [include/linux/string.h] 6974f0c455:  kernel_BUG_at_lib/string.c Daniel Micay <danielmicay@gmail.com> - 2017-07-26 04:40 +0200

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