Signal masks are false positives, we already check for SigBlk and SigCgt
but we missed SigIgn.

Add SigIgn to false positive check.

Signed-off-by: Tobin C. Harding <me@tobin.cc>

Currently script can stall if we read certain files (like
/proc/kmsg). While we have a mechanism to skip these files once they are
discovered it would be nice to not stall on as yet undiscovered files of
this kind.

Set a timer before each file is parsed, warn user if timer expires.

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tobin C. Harding <me@tobin.cc>

Currently script is targeted at x86_64. We can support other
architectures by using the correct regular expressions for each
architecture.

Add the infrastructure to support multiple architectures. Add support
for ppc64.

Signed-off-by: Tobin C. Harding <me@tobin.cc>

Currently script just dumps all results found. Potentially, this risks
losing single results among multiple duplicate results. We need some
way of restricting duplicates to assist users of the script. It would
also be nice if we got a report instead of raw results.

Duplicates can be defined in various ways, instead of trying to find a
single perfect solution we can present the user with various options to
display the output. Doing so will typically lead to users wanting to
view the output multiple times. Currently we scan the kernel each time,
this is slow and unnecessary. We can expedite the process by writing the
results to file for subsequent viewing.

Add command line options to enable summary reporting, including options
to write to and read from file.

Signed-off-by: Tobin C. Harding <me@tobin.cc>

There are a couple more files that cause the script to stall.

/sys/firmware/devicetree and its symlink /proc/device-tree, reported by
Michael Ellerman.

usbmon should be skipped were ever it appears. Reported by Kees Cook

Add files to be excluded from parsing.

Signed-off-by: Tobin C. Harding <me@tobin.cc>

Fix typo in comment string.

Signed-off-by: Tobin C. Harding <me@tobin.cc>

Currently script accepts files to skip. This was added to make running
the script faster (for repeat runs). We can remove this functionality in
preparation for adding sub commands (scan and format) to the script.

Remove command line options.

Signed-off-by: Tobin C. Harding <me@tobin.cc>

debug_arrays is not called. Also, %seen hash is not used. We should
remove unused code.

Remove dead code.

Signed-off-by: Tobin C. Harding <me@tobin.cc>

Current code uses spaces instead of tabs in places.

Use tabs instead of spaces.

Signed-off-by: Tobin C. Harding <me@tobin.cc>

Currently we are leaking addresses from the kernel to user space. This
script is an attempt to find some of those leakages. Script parses
`dmesg` output and /proc and /sys files for hex strings that look like
kernel addresses.

Only works for 64 bit kernels, the reason being that kernel addresses on
64 bit kernels have 'ffff' as the leading bit pattern making greping
possible. On 32 kernels we don't have this luxury.

Scripts is _slightly_ smarter than a straight grep, we check for false
positives (all 0's or all 1's, and vsyscall start/finish addresses).

[ I think there is a lot of room for improvement here, but it's already
  useful, so I'm merging it as-is. The whole "hash %p format" series is
  expected to go into 4.15, but will not fix %x users, and will not
  incentivize people to look at what they are leaking.     - Linus ]

Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>