sandbox: Correct compiler warnings in cmd_bootm/cmd_ximg

Correct the following warnings found with sandbox when compression
is enabled.

cmd_bootm.c: In function 'bootm_load_os':
cmd_bootm.c:443:11: warning: passing argument 4 of 'lzop_decompress' from incompatible pointer type [enabled by default]
/usr/local/google/c/cosarm/src/third_party/u-boot/files/include/linux/lzo.h:31:5: note: expected 'size_t *' but argument is of type 'uint *'
cmd_ximg.c: In function 'do_imgextract':
cmd_ximg.c:225:6: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
cmd_ximg.c:225:14: warning: 'hdr' may be used uninitialized in this function [-Wuninitialized]

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
sandbox: add compression tests

This adds the "test_compression" command when building the sandbox. This
tests the existing compression and decompression routines for simple
sanity and for buffer overflow conditions.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
documentation: add more compression configs

This adds the missing compression config items to the README.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
gzip: correctly bounds-check output buffer

The output buffer size must not be reset by the gzip decoder or there
is a risk of overflowing memory during decompression.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
lzma: correctly bounds-check output buffer

The output buffer size must be correctly passed to the lzma decoder or
there is a risk of overflowing memory during decompression. Switching
to the LZMA_FINISH_END mode means nothing is left in an unknown state
once the buffer becomes full.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
lzo: correctly bounds-check output buffer

This checks the size of the output buffer and fails if it was going to
overflow the buffer during lzo decompression.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
bootm: allow correct bounds-check of destination

While nothing presently examines the destination size, it should at
least be correct so that future users of sys_mapmem() will not be
surprised. Without this, it might be possible to overflow memory.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>