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2013-09-11lib/decompressors: fix "no limit" output buffer lengthAlexandre Courbot
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>
2011-01-13decompressors: check input size in decompress_inflate.cLasse Collin
Check for end of the input buffer when skipping over the filename field in the .gz file header. Signed-off-by: Lasse Collin <lasse.collin@tukaani.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Alain Knaff <alain@knaff.lu> Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com> Cc: Phillip Lougher <phillip@lougher.demon.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13Decompressors: include <linux/slab.h> in <linux/decompress/mm.h>Lasse Collin
Currently users of mm.h need to include <linux/slab.h> to use the macros malloc() and free() provided by mm.h. This fixes it. Signed-off-by: Lasse Collin <lasse.collin@tukaani.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Alain Knaff <alain@knaff.lu> Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com> Cc: Phillip Lougher <phillip@lougher.demon.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13Decompressors: get rid of set_error_fn() macroLasse Collin
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 <lasse.collin@tukaani.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Alain Knaff <alain@knaff.lu> Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com> Cc: Phillip Lougher <phillip@lougher.demon.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13Decompressors: add missing INIT (i.e. __init)Lasse Collin
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Alain Knaff <alain@knaff.lu> Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com> Cc: Phillip Lougher <phillip@lougher.demon.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24lzma/gzip: fix potential oops when input data is truncatedPhillip Lougher
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 <phillip@lougher.demon.co.uk> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-07lib/decompress_*: only include <linux/slab.h> if STATIC is not definedAlbin Tonnerre
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 <albin.tonnerre@free-electrons.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> Cc: Phillip Lougher <phillip@lougher.demon.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-07bzip2/lzma/gzip: fix comments describing decompressor APIPhillip Lougher
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 <phillip@lougher.demon.co.uk> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-03kmemtrace, kbuild: fix slab.h dependency problem in lib/decompress_inflate.cPekka Enberg
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 <penberg@cs.helsinki.fi> Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> LKML-Reference: <1237886030.25315.47.camel@penberg-laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-08bzip2/lzma: fix decompress_inflate.c vs multi-block-with-embedded-filenameAlain Knaff
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 <alain@knaff.lu> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-01-08bzip2/lzma: fix constant in decompress_inflateH. Peter Anvin
Impact: Cleanup Fix constant 0x8100 /* 32K */; according to Alain the value 0x8100 was left over test code to test misalignment, the correct value is indeed 0x8000 == 32K. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-01-04bzip2/lzma: library support for gzip, bzip2 and lzma decompressionAlain Knaff
Impact: Replaces inflate.c with a wrapper around zlib_inflate; new library code This is the first part of the bzip2/lzma patch The bzip patch is based on an idea by Christian Ludwig, includes support for compressing the kernel with bzip2 or lzma rather than gzip. Both compressors give smaller sizes than gzip. Lzma's decompresses faster than bzip2. It also supports ramdisks and initramfs' compressed using these two compressors. The functionality has been successfully used for a couple of years by the udpcast project This version applies to "tip" kernel 2.6.28 This part contains: - changed inflate.c to accomodate rest of patch - implementation of bzip2 compression (not used at this stage yet) - implementation of lzma compression (not used at this stage yet) - Makefile routines to support bzip2 and lzma kernel compression Signed-off-by: Alain Knaff <alain@knaff.lu> Signed-off-by: H. Peter Anvin <hpa@zytor.com>