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The lzo decompressor can, if given some really crazy data, possibly
overrun some variable types.  Modify the checking logic to properly
detect overruns before they happen.
Reported-by: "Don A. Bailey" <donb@securitymouse.com>
Tested-by: "Don A. Bailey" <donb@securitymouse.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This commit updates the kernel LZO code to the current upsteam version
which features a significant speed improvement - benchmarking the Calgary
and Silesia test corpora typically shows a doubled performance in
both compression and decompression on modern i386/x86_64/powerpc machines.
Signed-off-by: Markus F.X.J. Oberhumer <markus@oberhumer.com>

Rename the source file to match the function name and thereby
also make room for a possible future even slightly faster
"non-safe" decompressor version.
Signed-off-by: Markus F.X.J. Oberhumer <markus@oberhumer.com>

This patch series adds generic support for creating and extracting
LZO-compressed kernel images, as well as support for using such images on
the x86 and ARM architectures, and support for creating and using
LZO-compressed initrd and initramfs images.

Russell King said:

: Testing on a Cortex A9 model:
: - lzo decompressor is 65% of the time gzip takes to decompress a kernel
: - lzo kernel is 9% larger than a gzip kernel
:
: which I'm happy to say confirms your figures when comparing the two.
:
: However, when comparing your new gzip code to the old gzip code:
: - new is 99% of the size of the old code
: - new takes 42% of the time to decompress than the old code
:
: What this means is that for a proper comparison, the results get even better:
: - lzo is 7.5% larger than the old gzip'd kernel image
: - lzo takes 28% of the time that the old gzip code took
:
: So the expense seems definitely worth the effort.  The only reason I
: can think of ever using gzip woul...

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Shift of a LE value seems strange, probably meant to shift the cpu-order
variable as in the prvious section of the switch statement.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is a hybrid version of the patch to add the LZO1X compression
algorithm to the kernel.  Nitin and myself have merged the best parts of
the various patches to form this version which we're both happy with (and
are jointly signing off).

The performance of this version is equivalent to the original minilzo code
it was based on.  Bytecode comparisons have also been made on ARM, i386 and
x86_64 with favourable results.

There are several users of LZO lined up including jffs2, crypto and reiser4
since its much faster than zlib.
Signed-off-by: Nitin Gupta <nitingupta910@gmail.com>
Signed-off-by: Richard Purdie <rpurdie@openedhand.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>