linux-toradex.git/lib/decompress_inflate.c, branch v3.10.69

lib/decompressors: fix "no limit" output buffer length

2014-02-06T19:08:12+00:00

commit 1431574a1c4c669a0c198e4763627837416e4443 upstream.

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 
Tested-by: Jon Medhurst 
Cc: Stephen Warren 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Mark Brown 
Signed-off-by: Greg Kroah-Hartman

decompressors: check input size in decompress_inflate.c

2011-01-13T16:03:25+00:00

Check for end of the input buffer when skipping over the filename field in
the .gz file header.

Signed-off-by: Lasse Collin 
Cc: "H. Peter Anvin" 
Cc: Alain Knaff 
Cc: Albin Tonnerre 
Cc: Phillip Lougher 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Decompressors: include in

2011-01-13T16:03:23+00:00

Currently users of mm.h need to include  to use the macros
malloc() and free() provided by mm.h.  This fixes it.

Signed-off-by: Lasse Collin 
Cc: "H. Peter Anvin" 
Cc: Alain Knaff 
Cc: Albin Tonnerre 
Cc: Phillip Lougher 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Decompressors: get rid of set_error_fn() macro

2011-01-13T16:03:23+00:00

set_error_fn() has become a useless complication after c1e7c3ae59
("bzip2/lzma/gzip: pre-boot malloc doesn't return NULL on failure") fixed
the use of error() in malloc().  Only decompress_unlzma.c had some use for
it and that was easy to change too.

This also gets rid of the static function pointer "error", which
should have been marked as __initdata.

Signed-off-by: Lasse Collin 
Cc: "H. Peter Anvin" 
Cc: Alain Knaff 
Cc: Albin Tonnerre 
Cc: Phillip Lougher 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Decompressors: add missing INIT (i.e. __init)

2011-01-13T16:03:23+00:00

Signed-off-by: Lasse Collin 
Cc: "H. Peter Anvin" 
Cc: Alain Knaff 
Cc: Albin Tonnerre 
Cc: Phillip Lougher 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lzma/gzip: fix potential oops when input data is truncated

2009-09-24T14:21:05+00:00

If the lzma/gzip decompressors are called with insufficient input data
(len > 0 & fill = NULL), they will attempt to call the fill function to
obtain more data, leading to a kernel oops.

Signed-off-by: Phillip Lougher 
Cc: "H. Peter Anvin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/decompress_*: only include if STATIC is not defined

2009-08-07T17:39:56+00:00

These includes were added by 079effb6933f34b9b1b67b08bd4fd7fb672d16ef
("kmemtrace, kbuild: fix slab.h dependency problem in
lib/decompress_inflate.c") to fix the build when using kmemtrace.  However
this is not necessary when used to create a compressed kernel, and
actually creates issues (brings a lot of things unavailable in the
decompression environment), so don't include it if STATIC is defined.

Signed-off-by: Albin Tonnerre 
Cc: Sam Ravnborg 
Cc: Russell King 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Cc: Pekka Enberg 
Cc: Eduard - Gabriel Munteanu 
Cc: Phillip Lougher 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

bzip2/lzma/gzip: fix comments describing decompressor API

2009-08-07T17:39:56+00:00

Fix and improve comments in decompress/generic.h that describe the
decompressor API.  Also remove an unused definition, and rename INBUF_LEN
in lib/decompress_inflate.c to conform to bzip2/lzma naming.

Signed-off-by: Phillip Lougher 
Cc: "H. Peter Anvin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kmemtrace, kbuild: fix slab.h dependency problem in lib/decompress_inflate.c

2009-04-03T10:21:36+00:00

Impact: fix build

lib/decompress_inflate.c depends on slab.h without including it:

    CC      lib/decompress_inflate.o
  lib/decompress_inflate.c: In function ‘gunzip’:
  lib/decompress_inflate.c:45: error: implicit declaration of function ‘kmalloc’
  lib/decompress_inflate.c:45: warning: assignment makes pointer from integer without a cast
  lib/decompress_inflate.c:57: warning: assignment makes pointer from integer without a cast
  lib/decompress_inflate.c:65: warning: assignment makes pointer from integer without a cast
  lib/decompress_inflate.c:71: warning: assignment makes pointer from integer without a cast
  lib/decompress_inflate.c:154: error: implicit declaration of function ‘kfree’
  make[1]: *** [lib/decompress_inflate.o] Error 1
  make: *** [lib/] Error 2

It gets included implicitly currently - but this will not be the
case with upcoming kmemtrace changes.

Signed-off-by: Pekka Enberg 
Cc: Eduard - Gabriel Munteanu 
LKML-Reference: <1237886030.25315.47.camel@penberg-laptop>
Signed-off-by: Ingo Molnar

bzip2/lzma: fix decompress_inflate.c vs multi-block-with-embedded-filename

2009-01-08T23:10:19+00:00

Impact: Bug fix

Fix gunzip uncompression, so that it also works with files with
embedded filenames that are larger than one block.

Signed-off-by: Alain Knaff 
Signed-off-by: H. Peter Anvin