Go to file
Phillip Lougher e812cbbbbb squashfs: avoid out of bounds writes in decompressors
Patch series "Squashfs: fix BIO migration regression and add sanity checks".

Patch [1/4] fixes a regression introduced by the "migrate from
ll_rw_block usage to BIO" patch, which has produced a number of
Sysbot/Syzkaller reports.

Patches [2/4], [3/4], and [4/4] fix a number of filesystem corruption
issues which have produced Sysbot reports in the id, inode and xattr
lookup code.

Each patch has been tested against the Sysbot reproducers using the
given kernel configuration.  They have the appropriate "Reported-by:"
lines added.

Additionally, all of the reproducer filesystems are indirectly fixed by
patch [4/4] due to the fact they all have xattr corruption which is now
detected there.

Additional testing with other configurations and architectures (32bit,
big endian), and normal filesystems has also been done to trap any
inadvertent regressions caused by the additional sanity checks.

This patch (of 4):

This is a regression introduced by the patch "migrate from ll_rw_block
usage to BIO".

Sysbot/Syskaller has reported a number of "out of bounds writes" and
"unable to handle kernel paging request in squashfs_decompress" errors
which have been identified as a regression introduced by the above
patch.

Specifically, the patch removed the following sanity check

        if (length < 0 || length > output->length ||
		(index + length) > msblk->bytes_used)

This check did two things:

1. It ensured any reads were not beyond the end of the filesystem

2. It ensured that the "length" field read from the filesystem
   was within the expected maximum length.  Without this any
   corrupted values can over-run allocated buffers.

Link: https://lkml.kernel.org/r/20210204130249.4495-1-phillip@squashfs.org.uk
Link: https://lkml.kernel.org/r/20210204130249.4495-2-phillip@squashfs.org.uk
Fixes: 93e72b3c61 ("squashfs: migrate from ll_rw_block usage to BIO")
Reported-by: syzbot+6fba78f99b9afd4b5634@syzkaller.appspotmail.com
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Philippe Liard <pliard@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-09 17:26:44 -08:00
Documentation - For syscall user dispatch, separate ptctl operation from syscall 2021-02-07 10:16:24 -08:00
LICENSES LICENSES: Add the CC-BY-4.0 license 2020-12-08 10:33:27 -07:00
arch - For syscall user dispatch, separate ptctl operation from syscall 2021-02-07 10:16:24 -08:00
block block-5.11-2021-02-05 2021-02-06 14:40:27 -08:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto X.509: Fix crash caused by NULL pointer 2021-01-20 11:33:51 -08:00
drivers libnvdimm for 5.11-rc7 2021-02-07 10:45:26 -08:00
fs squashfs: avoid out of bounds writes in decompressors 2021-02-09 17:26:44 -08:00
include - Prevent device managed IRQ allocation helpers from returning IRQ 0. 2021-02-07 10:25:01 -08:00
init init/gcov: allow CONFIG_CONSTRUCTORS on UML to fix module gcov 2021-02-05 11:03:47 -08:00
ipc Merge branch 'akpm' (patches from Andrew) 2020-12-15 12:53:37 -08:00
kernel tracing: Fix output of top level event "enable" file 2021-02-08 11:32:39 -08:00
lib - Revert an attempt to not spread IRQ threads on isolated CPUs which has 2021-02-07 10:03:43 -08:00
mm mm: hugetlb: fix missing put_page in gather_surplus_pages() 2021-02-05 11:03:47 -08:00
net Fixes: 2021-02-05 10:11:14 -08:00
samples ARM: SoC drivers for v5.11 2020-12-16 16:38:41 -08:00
scripts kallsyms: fix nonconverging kallsyms table with lld 2021-02-05 17:53:28 +09:00
security cap: fix conversions on getxattr 2021-01-28 10:22:48 +01:00
sound ALSA: hda/via: Apply the workaround generically for Clevo machines 2021-01-26 18:05:03 +01:00
tools libnvdimm for 5.11-rc7 2021-02-07 10:45:26 -08:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt KVM/arm64 fixes for 5.11, take #2 2021-01-25 18:52:01 -05:00
.clang-format clang-format: Update with the latest for_each macro list 2021-01-29 15:00:23 +01:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: docs: ignore sphinx_*/ directories 2020-09-10 10:44:31 -06:00
.mailmap block-5.11-2021-02-05 2021-02-06 14:40:27 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: dccp: move Gerrit Renker to CREDITS 2021-01-14 10:53:49 -08:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS/.mailmap: use my @kernel.org address 2021-02-05 11:03:47 -08:00
Makefile Linux 5.11-rc7 2021-02-07 13:57:38 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.