linux/lib/decompress_inflate.c

185 lines
3.8 KiB
C
Raw Normal View History

#ifdef STATIC
/* Pre-boot environment: included */
/* prevent inclusion of _LINUX_KERNEL_H in pre-boot environment: lots
* errors about console_printk etc... on ARM */
#define _LINUX_KERNEL_H
#include "zlib_inflate/inftrees.c"
#include "zlib_inflate/inffast.c"
#include "zlib_inflate/inflate.c"
#else /* STATIC */
/* initramfs et al: linked */
#include <linux/zutil.h>
#include "zlib_inflate/inftrees.h"
#include "zlib_inflate/inffast.h"
#include "zlib_inflate/inflate.h"
#include "zlib_inflate/infutil.h"
#include <linux/decompress/inflate.h>
#endif /* STATIC */
#include <linux/decompress/mm.h>
#define GZIP_IOBUF_SIZE (16*1024)
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 21:23:14 +00:00
static long INIT nofill(void *buffer, unsigned long len)
{
return -1;
}
/* Included from initramfs et al code */
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 21:23:14 +00:00
STATIC int INIT gunzip(unsigned char *buf, long len,
long (*fill)(void*, unsigned long),
long (*flush)(void*, unsigned long),
unsigned char *out_buf,
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 21:23:14 +00:00
long *pos,
void(*error)(char *x)) {
u8 *zbuf;
struct z_stream_s *strm;
int rc;
size_t out_len;
rc = -1;
if (flush) {
out_len = 0x8000; /* 32 K */
out_buf = malloc(out_len);
} else {
lib/decompressors: fix "no limit" output buffer length When decompressing into memory, the output buffer length is set to some arbitrarily high value (0x7fffffff) to indicate the output is, virtually, unlimited in size. The problem with this is that some platforms have their physical memory at high physical addresses (0x80000000 or more), and that the output buffer address and its "unlimited" length cannot be added without overflowing. An example of this can be found in inflate_fast(): /* next_out is the output buffer address */ out = strm->next_out - OFF; /* avail_out is the output buffer size. end will overflow if the output * address is >= 0x80000104 */ end = out + (strm->avail_out - 257); This has huge consequences on the performance of kernel decompression, since the following exit condition of inflate_fast() will be always true: } while (in < last && out < end); Indeed, "end" has overflowed and is now always lower than "out". As a result, inflate_fast() will return after processing one single byte of input data, and will thus need to be called an unreasonably high number of times. This probably went unnoticed because kernel decompression is fast enough even with this issue. Nonetheless, adjusting the output buffer length in such a way that the above pointer arithmetic never overflows results in a kernel decompression that is about 3 times faster on affected machines. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Tested-by: Jon Medhurst <tixy@linaro.org> Cc: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 21:23:53 +00:00
out_len = ((size_t)~0) - (size_t)out_buf; /* no limit */
}
if (!out_buf) {
error("Out of memory while allocating output buffer");
goto gunzip_nomem1;
}
if (buf)
zbuf = buf;
else {
zbuf = malloc(GZIP_IOBUF_SIZE);
len = 0;
}
if (!zbuf) {
error("Out of memory while allocating input buffer");
goto gunzip_nomem2;
}
strm = malloc(sizeof(*strm));
if (strm == NULL) {
error("Out of memory while allocating z_stream");
goto gunzip_nomem3;
}
strm->workspace = malloc(flush ? zlib_inflate_workspacesize() :
sizeof(struct inflate_state));
if (strm->workspace == NULL) {
error("Out of memory while allocating workspace");
goto gunzip_nomem4;
}
if (!fill)
fill = nofill;
if (len == 0)
len = fill(zbuf, GZIP_IOBUF_SIZE);
/* verify the gzip header */
if (len < 10 ||
zbuf[0] != 0x1f || zbuf[1] != 0x8b || zbuf[2] != 0x08) {
if (pos)
*pos = 0;
error("Not a gzip file");
goto gunzip_5;
}
/* skip over gzip header (1f,8b,08... 10 bytes total +
* possible asciz filename)
*/
strm->next_in = zbuf + 10;
strm->avail_in = len - 10;
/* skip over asciz filename */
if (zbuf[3] & 0x8) {
do {
/*
* If the filename doesn't fit into the buffer,
* the file is very probably corrupt. Don't try
* to read more data.
*/
if (strm->avail_in == 0) {
error("header error");
goto gunzip_5;
}
--strm->avail_in;
} while (*strm->next_in++);
}
strm->next_out = out_buf;
strm->avail_out = out_len;
rc = zlib_inflateInit2(strm, -MAX_WBITS);
if (!flush) {
WS(strm)->inflate_state.wsize = 0;
WS(strm)->inflate_state.window = NULL;
}
while (rc == Z_OK) {
if (strm->avail_in == 0) {
/* TODO: handle case where both pos and fill are set */
len = fill(zbuf, GZIP_IOBUF_SIZE);
if (len < 0) {
rc = -1;
error("read error");
break;
}
strm->next_in = zbuf;
strm->avail_in = len;
}
rc = zlib_inflate(strm, 0);
/* Write any data generated */
if (flush && strm->next_out > out_buf) {
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 21:23:14 +00:00
long l = strm->next_out - out_buf;
if (l != flush(out_buf, l)) {
rc = -1;
error("write error");
break;
}
strm->next_out = out_buf;
strm->avail_out = out_len;
}
/* after Z_FINISH, only Z_STREAM_END is "we unpacked it all" */
if (rc == Z_STREAM_END) {
rc = 0;
break;
} else if (rc != Z_OK) {
error("uncompression error");
rc = -1;
}
}
zlib_inflateEnd(strm);
if (pos)
/* add + 8 to skip over trailer */
*pos = strm->next_in - zbuf+8;
gunzip_5:
free(strm->workspace);
gunzip_nomem4:
free(strm);
gunzip_nomem3:
if (!buf)
free(zbuf);
gunzip_nomem2:
if (flush)
free(out_buf);
gunzip_nomem1:
return rc; /* returns Z_OK (0) if successful */
}
#define decompress gunzip