kernel/linux.git/lib/xz, branch v4.19.283

lib/xz: Validate the value before assigning it to an enum variable

2021-11-26T10:36:06+00:00

[ Upstream commit 4f8d7abaa413c34da9d751289849dbfb7c977d05 ] This might matter, for example, if the underlying type of enum xz_check was a signed char. In such a case the validation wouldn't have caught an unsupported header. I don't know if this problem can occur in the kernel on any arch but it's still good to fix it because some people might copy the XZ code to their own projects from Linux instead of the upstream XZ Embedded repository. This change may increase the code size by a few bytes. An alternative would have been to use an unsigned int instead of enum xz_check but using an enumeration looks cleaner. Link: https://lore.kernel.org/r/20211010213145.17462-3-xiang@kernel.org Signed-off-by: Lasse Collin Signed-off-by: Gao Xiang Signed-off-by: Sasha Levin

lib/xz: Avoid overlapping memcpy() with invalid input with in-place decompression

2021-11-26T10:36:06+00:00

[ Upstream commit 83d3c4f22a36d005b55f44628f46cc0d319a75e8 ] With valid files, the safety margin described in lib/decompress_unxz.c ensures that these buffers cannot overlap. But if the uncompressed size of the input is larger than the caller thought, which is possible when the input file is invalid/corrupt, the buffers can overlap. Obviously the result will then be garbage (and usually the decoder will return an error too) but no other harm will happen when such an over-run occurs. This change only affects uncompressed LZMA2 chunks and so this should have no effect on performance. Link: https://lore.kernel.org/r/20211010213145.17462-2-xiang@kernel.org Signed-off-by: Lasse Collin Signed-off-by: Gao Xiang Signed-off-by: Sasha Levin

lib/xz: Put CRC32_POLY_LE in xz_private.h

2018-10-01T22:44:59+00:00

This fixes a regression introduced by faa16bc404d72a5 ("lib: Use existing define with polynomial"). The cleanup added a dependency on include/linux, which broke the PowerPC boot wrapper/decompresser when KERNEL_XZ is enabled: BOOTCC arch/powerpc/boot/decompress.o In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:233, from arch/powerpc/boot/decompress.c:42: arch/powerpc/boot/../../../lib/xz/xz_crc32.c:18:10: fatal error: linux/crc32poly.h: No such file or directory #include ^~~~~~~~~~~~~~~~~~~ The powerpc decompresser is a hairy corner of the kernel. Even while building a 64-bit kernel it needs to build a 32-bit binary and therefore avoid including files from include/linux. This allows users of the xz library to avoid including headers from 'include/linux/' while still achieving the cleanup of the magic number. Fixes: faa16bc404d72a5 ("lib: Use existing define with polynomial") Reported-by: Meelis Roos Reported-by: kbuild test robot Suggested-by: Christophe LEROY Signed-off-by: Joel Stanley Tested-by: Meelis Roos Signed-off-by: Michael Ellerman

lib: Use existing define with polynomial

2018-07-27T11:16:38+00:00

Do not define again the polynomial but use header with existing define. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Herbert Xu

lib/xz: Add fall-through comments to a switch statement

2017-10-12T13:10:12+00:00

It's good style. I was also told that GCC 7 is more strict and might give a warning when such comments are missing. Signed-off-by: Lasse Collin Suggested-by: Andrei Borzenkov Signed-off-by: Jiri Kosina

lib/xz: enable all filters by default in Kconfig

2014-06-04T23:54:18+00:00

This restores the old behavior that existed before 2013-02-22, when changes were made by 64dbfb444c150 ("decompressors: drop dependency on CONFIG_EXPERT") and 5dc49c75a2 ("decompressors: make the default XZ_DEC_* config match the selected architecture"). Disabling the filters only makes sense on embedded systems. Signed-off-by: Lasse Collin Acked-by: Kyle McMartin Cc: Florian Fainelli Cc: Phillip Lougher Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/xz: add comments for the intentionally missing break statements

2014-06-04T23:54:18+00:00

Signed-off-by: Lasse Collin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

decompressors: fix typo "POWERPC"

2013-03-13T22:21:48+00:00

Commit 5dc49c75a26b ("decompressors: make the default XZ_DEC_* config match the selected architecture") added default y if POWERPC to lib/xz/Kconfig. But there is no Kconfig symbol POWERPC. The most general Kconfig symbol for the powerpc architecture is PPC. So let's use that. Signed-off-by: Paul Bolle Cc: Florian Fainelli Cc: Lasse Collin Cc: Benjamin Herrenschmidt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

decompressors: make the default XZ_DEC_* config match the selected architecture

2013-02-22T01:22:26+00:00

Change the defautl XZ_DEC_* config symbol to match the configured architecture. It is perfectly legitimate to support multiple XZ BCJ filters for different architectures (e.g.: to mount foreign squashfs/xz compressed filesystems), it is however more natural not to select them all by default, but only the one matching the configured architecture. Signed-off-by: Florian Fainelli Acked-by: Lasse Collin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

decompressors: drop dependency on CONFIG_EXPERT

2013-02-22T01:22:26+00:00

Remove the XZ_DEC_* depedencey on CONFIG_EXPERT as recommended by Lasse Colin. Signed-off-by: Florian Fainelli Acked-by: Lasse Collin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds