summaryrefslogtreecommitdiffstats
path: root/lib/decompress_unlz4.c
AgeCommit message (Collapse)AuthorFilesLines
2021-07-01lib/decompress_unlz4.c: correctly handle zero-padding around initrds.Dimitri John Ledkov1-0/+8
lz4 compatible decompressor is simple. The format is underspecified and relies on EOF notification to determine when to stop. Initramfs buffer format[1] explicitly states that it can have arbitrary number of zero padding. Thus when operating without a fill function, be extra careful to ensure that sizes less than 4, or apperantly empty chunksizes are treated as EOF. To test this I have created two cpio initrds, first a normal one, main.cpio. And second one with just a single /test-file with content "second" second.cpio. Then i compressed both of them with gzip, and with lz4 -l. Then I created a padding of 4 bytes (dd if=/dev/zero of=pad4 bs=1 count=4). To create four testcase initrds: 1) main.cpio.gzip + extra.cpio.gzip = pad0.gzip 2) main.cpio.lz4 + extra.cpio.lz4 = pad0.lz4 3) main.cpio.gzip + pad4 + extra.cpio.gzip = pad4.gzip 4) main.cpio.lz4 + pad4 + extra.cpio.lz4 = pad4.lz4 The pad4 test-cases replicate the initrd load by grub, as it pads and aligns every initrd it loads. All of the above boot, however /test-file was not accessible in the initrd for the testcase #4, as decoding in lz4 decompressor failed. Also an error message printed which usually is harmless. Whith a patched kernel, all of the above testcases now pass, and /test-file is accessible. This fixes lz4 initrd decompress warning on every boot with grub. And more importantly this fixes inability to load multiple lz4 compressed initrds with grub. This patch has been shipping in Ubuntu kernels since January 2021. [1] ./Documentation/driver-api/early-userspace/buffer-format.rst BugLink: https://bugs.launchpad.net/bugs/1835660 Link: https://lore.kernel.org/lkml/20210114200256.196589-1-xnox@ubuntu.com/ # v0 Link: https://lkml.kernel.org/r/20210513104831.432975-1-dimitri.ledkov@canonical.com Signed-off-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com> Cc: Kyungsik Lee <kyungsik.lee@lge.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Bongkyu Kim <bongkyu.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Sven Schmidt <4sschmid@informatik.uni-hamburg.de> Cc: Rajat Asthana <thisisrast7@gmail.com> Cc: Nick Terrell <terrelln@fb.com> Cc: Gao Xiang <hsiangkao@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-24lib/decompress_unlz4: change module to work with new LZ4 module versionSven Schmidt1-5/+8
Update the unlz4 wrapper to work with the updated LZ4 kernel module version. Link: http://lkml.kernel.org/r/1486321748-19085-3-git-send-email-4sschmid@informatik.uni-hamburg.de Signed-off-by: Sven Schmidt <4sschmid@informatik.uni-hamburg.de> Cc: Bongkyu Kim <bongkyu.kim@lge.com> Cc: Rui Salvaterra <rsalvaterra@gmail.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: David S. Miller <davem@davemloft.net> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Kees Cook <keescook@chromium.org> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10lib/decompressors: use real out buf size for gunzip with kernelYinghai Lu1-3/+3
When loading x86 64bit kernel above 4GiB with patched grub2, got kernel gunzip error. | early console in decompress_kernel | decompress_kernel: | input: [0x807f2143b4-0x807ff61aee] | output: [0x807cc00000-0x807f3ea29b] 0x027ea29c: output_len | boot via startup_64 | KASLR using RDTSC... | new output: [0x46fe000000-0x470138cfff] 0x0338d000: output_run_size | decompress: [0x46fe000000-0x47007ea29b] <=== [0x807f2143b4-0x807ff61aee] | | Decompressing Linux... gz... | | uncompression error | | -- System halted the new buffer is at 0x46fe000000ULL, decompressor_gzip is using 0xffffffb901ffffff as out_len. gunzip in lib/zlib_inflate/inflate.c cap that len to 0x01ffffff and decompress fails later. We could hit this problem with crashkernel booting that uses kexec loading kernel above 4GiB. We have decompress_* support: 1. inbuf[]/outbuf[] for kernel preboot. 2. inbuf[]/flush() for initramfs 3. fill()/flush() for initrd. This bug only affect kernel preboot path that use outbuf[]. Add __decompress and take real out_buf_len for gunzip instead of guessing wrong buf size. Fixes: 1431574a1c4 (lib/decompressors: fix "no limit" output buffer length) Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: Alexandre Courbot <acourbot@nvidia.com> Cc: Jon Medhurst <tixy@linaro.org> Cc: Stephen Warren <swarren@wwwdotorg.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08initramfs: support initramfs that is bigger than 2GiBYinghai Lu1-9/+9
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>
2014-08-08initrd: fix lz4 decompress with initrdYinghai Lu1-22/+43
During testing initrd (>2G) support, find decompress/lz4 does not work with initrd at all. decompress_* should support: 1. inbuf[]/outbuf[] for kernel preboot. 2. inbuf[]/flush() for initramfs 3. fill()/flush() for initrd. in the unlz4 does not handle case 3, as input len is passed as 0, and it failed in first try. Fix that add one extra if (fill) checking, and get out if EOF from the fill(). Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: Kyungsik Lee <kyungsik.lee@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23lib/decompress_unlz4.c: always set an error return code on failuresJan Beulich1-0/+1
"ret", being set to -1 early on, gets cleared by the first invocation of lz4_decompress()/lz4_decompress_unknownoutputsize(), and hence subsequent failures wouldn't be noticed by the caller without setting it back to -1 right after those calls. Reported-by: Matthew Daley <mattjd@gmail.com> Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: Kyungsik Lee <kyungsik.lee@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09lib: add support for LZ4-compressed kernelKyungsik Lee1-0/+187
Add support for extracting LZ4-compressed kernel images, as well as LZ4-compressed ramdisk images in the kernel boot process. Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Florian Fainelli <florian@openwrt.org> Cc: Yann Collet <yann.collet.73@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>