linux/lib/decompress_unlzo.c
Yinghai Lu d97b07c54f initramfs: support initramfs that is bigger than 2GiB
Now with 64bit bzImage and kexec tools, we support ramdisk that size is
bigger than 2g, as we could put it above 4G.

Found compressed initramfs image could not be decompressed properly.  It
turns out that image length is int during decompress detection, and it
will become < 0 when length is more than 2G.  Furthermore, during
decompressing len as int is used for inbuf count, that has problem too.

Change len to long, that should be ok as on 32 bit platform long is
32bits.

Tested with following compressed initramfs image as root with kexec.
	gzip, bzip2, xz, lzma, lzop, lz4.
run time for populate_rootfs():
   size        name       Nehalem-EX  Westmere-EX  Ivybridge-EX
 9034400256 root_img     :   26s           24s          30s
 3561095057 root_img.lz4 :   28s           27s          27s
 3459554629 root_img.lzo :   29s           29s          28s
 3219399480 root_img.gz  :   64s           62s          49s
 2251594592 root_img.xz  :  262s          260s         183s
 2226366598 root_img.lzma:  386s          376s         277s
 2901482513 root_img.bz2 :  635s          599s

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Rashika Kheria <rashika.kheria@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: P J P <ppandit@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: "Daniel M. Weeks" <dan@danweeks.net>
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 15:57:26 -07:00

291 lines
6.8 KiB
C

/*
* LZO decompressor for the Linux kernel. Code borrowed from the lzo
* implementation by Markus Franz Xaver Johannes Oberhumer.
*
* Linux kernel adaptation:
* Copyright (C) 2009
* Albin Tonnerre, Free Electrons <albin.tonnerre@free-electrons.com>
*
* Original code:
* Copyright (C) 1996-2005 Markus Franz Xaver Johannes Oberhumer
* All Rights Reserved.
*
* lzop and the LZO library are free software; you can redistribute them
* and/or modify them under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING.
* If not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Markus F.X.J. Oberhumer
* <markus@oberhumer.com>
* http://www.oberhumer.com/opensource/lzop/
*/
#ifdef STATIC
#include "lzo/lzo1x_decompress_safe.c"
#else
#include <linux/decompress/unlzo.h>
#endif
#include <linux/types.h>
#include <linux/lzo.h>
#include <linux/decompress/mm.h>
#include <linux/compiler.h>
#include <asm/unaligned.h>
static const unsigned char lzop_magic[] = {
0x89, 0x4c, 0x5a, 0x4f, 0x00, 0x0d, 0x0a, 0x1a, 0x0a };
#define LZO_BLOCK_SIZE (256*1024l)
#define HEADER_HAS_FILTER 0x00000800L
#define HEADER_SIZE_MIN (9 + 7 + 4 + 8 + 1 + 4)
#define HEADER_SIZE_MAX (9 + 7 + 1 + 8 + 8 + 4 + 1 + 255 + 4)
STATIC inline long INIT parse_header(u8 *input, long *skip, long in_len)
{
int l;
u8 *parse = input;
u8 *end = input + in_len;
u8 level = 0;
u16 version;
/*
* Check that there's enough input to possibly have a valid header.
* Then it is possible to parse several fields until the minimum
* size may have been used.
*/
if (in_len < HEADER_SIZE_MIN)
return 0;
/* read magic: 9 first bits */
for (l = 0; l < 9; l++) {
if (*parse++ != lzop_magic[l])
return 0;
}
/* get version (2bytes), skip library version (2),
* 'need to be extracted' version (2) and
* method (1) */
version = get_unaligned_be16(parse);
parse += 7;
if (version >= 0x0940)
level = *parse++;
if (get_unaligned_be32(parse) & HEADER_HAS_FILTER)
parse += 8; /* flags + filter info */
else
parse += 4; /* flags */
/*
* At least mode, mtime_low, filename length, and checksum must
* be left to be parsed. If also mtime_high is present, it's OK
* because the next input buffer check is after reading the
* filename length.
*/
if (end - parse < 8 + 1 + 4)
return 0;
/* skip mode and mtime_low */
parse += 8;
if (version >= 0x0940)
parse += 4; /* skip mtime_high */
l = *parse++;
/* don't care about the file name, and skip checksum */
if (end - parse < l + 4)
return 0;
parse += l + 4;
*skip = parse - input;
return 1;
}
STATIC int INIT unlzo(u8 *input, long in_len,
long (*fill)(void *, unsigned long),
long (*flush)(void *, unsigned long),
u8 *output, long *posp,
void (*error) (char *x))
{
u8 r = 0;
long skip = 0;
u32 src_len, dst_len;
size_t tmp;
u8 *in_buf, *in_buf_save, *out_buf;
int ret = -1;
if (output) {
out_buf = output;
} else if (!flush) {
error("NULL output pointer and no flush function provided");
goto exit;
} else {
out_buf = malloc(LZO_BLOCK_SIZE);
if (!out_buf) {
error("Could not allocate output buffer");
goto exit;
}
}
if (input && fill) {
error("Both input pointer and fill function provided, don't know what to do");
goto exit_1;
} else if (input) {
in_buf = input;
} else if (!fill) {
error("NULL input pointer and missing fill function");
goto exit_1;
} else {
in_buf = malloc(lzo1x_worst_compress(LZO_BLOCK_SIZE));
if (!in_buf) {
error("Could not allocate input buffer");
goto exit_1;
}
}
in_buf_save = in_buf;
if (posp)
*posp = 0;
if (fill) {
/*
* Start from in_buf + HEADER_SIZE_MAX to make it possible
* to use memcpy() to copy the unused data to the beginning
* of the buffer. This way memmove() isn't needed which
* is missing from pre-boot environments of most archs.
*/
in_buf += HEADER_SIZE_MAX;
in_len = fill(in_buf, HEADER_SIZE_MAX);
}
if (!parse_header(in_buf, &skip, in_len)) {
error("invalid header");
goto exit_2;
}
in_buf += skip;
in_len -= skip;
if (fill) {
/* Move the unused data to the beginning of the buffer. */
memcpy(in_buf_save, in_buf, in_len);
in_buf = in_buf_save;
}
if (posp)
*posp = skip;
for (;;) {
/* read uncompressed block size */
if (fill && in_len < 4) {
skip = fill(in_buf + in_len, 4 - in_len);
if (skip > 0)
in_len += skip;
}
if (in_len < 4) {
error("file corrupted");
goto exit_2;
}
dst_len = get_unaligned_be32(in_buf);
in_buf += 4;
in_len -= 4;
/* exit if last block */
if (dst_len == 0) {
if (posp)
*posp += 4;
break;
}
if (dst_len > LZO_BLOCK_SIZE) {
error("dest len longer than block size");
goto exit_2;
}
/* read compressed block size, and skip block checksum info */
if (fill && in_len < 8) {
skip = fill(in_buf + in_len, 8 - in_len);
if (skip > 0)
in_len += skip;
}
if (in_len < 8) {
error("file corrupted");
goto exit_2;
}
src_len = get_unaligned_be32(in_buf);
in_buf += 8;
in_len -= 8;
if (src_len <= 0 || src_len > dst_len) {
error("file corrupted");
goto exit_2;
}
/* decompress */
if (fill && in_len < src_len) {
skip = fill(in_buf + in_len, src_len - in_len);
if (skip > 0)
in_len += skip;
}
if (in_len < src_len) {
error("file corrupted");
goto exit_2;
}
tmp = dst_len;
/* When the input data is not compressed at all,
* lzo1x_decompress_safe will fail, so call memcpy()
* instead */
if (unlikely(dst_len == src_len))
memcpy(out_buf, in_buf, src_len);
else {
r = lzo1x_decompress_safe((u8 *) in_buf, src_len,
out_buf, &tmp);
if (r != LZO_E_OK || dst_len != tmp) {
error("Compressed data violation");
goto exit_2;
}
}
if (flush && flush(out_buf, dst_len) != dst_len)
goto exit_2;
if (output)
out_buf += dst_len;
if (posp)
*posp += src_len + 12;
in_buf += src_len;
in_len -= src_len;
if (fill) {
/*
* If there happens to still be unused data left in
* in_buf, move it to the beginning of the buffer.
* Use a loop to avoid memmove() dependency.
*/
if (in_len > 0)
for (skip = 0; skip < in_len; ++skip)
in_buf_save[skip] = in_buf[skip];
in_buf = in_buf_save;
}
}
ret = 0;
exit_2:
if (!input)
free(in_buf_save);
exit_1:
if (!output)
free(out_buf);
exit:
return ret;
}
#define decompress unlzo