The source for the Linux kernel used in Windows Subsystem for Linux 2 (WSL2)
Перейти к файлу
Dave Chinner 6f021e4ef3 xfs: validate cached inodes are free when allocated
commit afca6c5b25 upstream.

A recent fuzzed filesystem image cached random dcache corruption
when the reproducer was run. This often showed up as panics in
lookup_slow() on a null inode->i_ops pointer when doing pathwalks.

BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
....
Call Trace:
 lookup_slow+0x44/0x60
 walk_component+0x3dd/0x9f0
 link_path_walk+0x4a7/0x830
 path_lookupat+0xc1/0x470
 filename_lookup+0x129/0x270
 user_path_at_empty+0x36/0x40
 path_listxattr+0x98/0x110
 SyS_listxattr+0x13/0x20
 do_syscall_64+0xf5/0x280
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

but had many different failure modes including deadlocks trying to
lock the inode that was just allocated or KASAN reports of
use-after-free violations.

The cause of the problem was a corrupt INOBT on a v4 fs where the
root inode was marked as free in the inobt record. Hence when we
allocated an inode, it chose the root inode to allocate, found it in
the cache and re-initialised it.

We recently fixed a similar inode allocation issue caused by inobt
record corruption problem in xfs_iget_cache_miss() in commit
ee457001ed ("xfs: catch inode allocation state mismatch
corruption"). This change adds similar checks to the cache-hit path
to catch it, and turns the reproducer into a corruption shutdown
situation.

Reported-by: Wen Xu <wen.xu@gatech.edu>
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: fix typos in comment]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-09 12:16:39 +02:00
Documentation net: dsa: qca8k: Add QCA8334 binding documentation 2018-08-03 07:50:44 +02:00
arch kvm: x86: vmx: fix vpid leak 2018-08-06 16:20:49 +02:00
block block: reset bi_iter.bi_done after splitting bio 2018-08-03 07:50:42 +02:00
certs License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
crypto crypto: authenc - don't leak pointers to authenc keys 2018-08-03 07:50:40 +02:00
drivers intel_idle: Graceful probe failure when MWAIT is disabled 2018-08-09 12:16:39 +02:00
firmware License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fs xfs: validate cached inodes are free when allocated 2018-08-09 12:16:39 +02:00
include ring_buffer: tracing: Inherit the tracing setting to next ring buffer 2018-08-09 12:16:38 +02:00
init init: fix false positives in W+X checking 2018-06-21 04:02:57 +09:00
ipc ipc/shm: fix shmat() nil address after round-down when remapping 2018-05-30 07:51:49 +02:00
kernel ring_buffer: tracing: Inherit the tracing setting to next ring buffer 2018-08-09 12:16:38 +02:00
lib lib/rhashtable: consider param->min_size when setting initial table size 2018-07-25 11:25:09 +02:00
mm mm/slub.c: add __printf verification to slab_err() 2018-08-03 07:50:23 +02:00
net netlink: Don't shift on 64 for ngroups 2018-08-09 12:16:38 +02:00
samples samples/bpf: Partially fixes the bpf.o build 2018-04-26 11:02:12 +02:00
scripts Kbuild: fix # escaping in .cmd files for future Make 2018-07-11 16:29:21 +02:00
security ima: based on policy verify firmware signatures (pre-allocated buffer) 2018-08-03 07:50:31 +02:00
sound ASoC: topology: Add missing clock gating parameter when parsing hw_configs 2018-08-03 07:50:42 +02:00
tools selftests: intel_pstate: return Kselftest Skip code for skipped tests 2018-08-03 07:50:27 +02:00
usr initramfs: fix initramfs rebuilds w/ compression after disabling 2017-11-03 07:39:19 -07:00
virt KVM/Eventfd: Avoid crash when assign and deassign specific eventfd in parallel. 2018-07-25 11:25:07 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: rpm-pkg: keep spec file until make mrproper 2018-02-13 10:19:46 +01:00
.mailmap .mailmap: Add Maciej W. Rozycki's Imagination e-mail address 2017-11-10 12:16:15 -08:00
COPYING [PATCH] update FSF address in COPYING 2005-09-10 10:06:29 -07:00
CREDITS MAINTAINERS: update TPM driver infrastructure changes 2017-11-09 17:58:40 -08:00
Kbuild License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
MAINTAINERS dt-bindings: Document mti,mips-cpc binding 2018-03-15 10:54:35 +01:00
Makefile Linux 4.14.61 2018-08-06 16:20:52 +02:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

README

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

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

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.