No description
  • C 96.8%
  • Assembly 0.9%
  • Rust 0.7%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Ming-Hung Tsai 135496c208 dm cache: fix flushing uninitialized delayed_work on cache_ctr error
An unexpected WARN_ON from flush_work() may occur when cache creation
fails, caused by destroying the uninitialized delayed_work waker in the
error path of cache_create(). For example, the warning appears on the
superblock checksum error.

Reproduce steps:

dmsetup create cmeta --table "0 8192 linear /dev/sdc 0"
dmsetup create cdata --table "0 65536 linear /dev/sdc 8192"
dmsetup create corig --table "0 524288 linear /dev/sdc 262144"
dd if=/dev/urandom of=/dev/mapper/cmeta bs=4k count=1 oflag=direct
dmsetup create cache --table "0 524288 cache /dev/mapper/cmeta \
/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0"

Kernel logs:

(snip)
WARNING: CPU: 0 PID: 84 at kernel/workqueue.c:4178 __flush_work+0x5d4/0x890

Fix by pulling out the cancel_delayed_work_sync() from the constructor's
error path. This patch doesn't affect the use-after-free fix for
concurrent dm_resume and dm_destroy (commit 6a459d8edb ("dm cache: Fix
UAF in destroy()")) as cache_dtr is not changed.

Signed-off-by: Ming-Hung Tsai <mtsai@redhat.com>
Fixes: 6a459d8edb ("dm cache: Fix UAF in destroy()")
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Joe Thornber <thornber@redhat.com>
History 2024-11-04 17:39:31 +01:00
arch
block
certs
crypto
Documentation
drivers
fs
include
init
io_uring
ipc
kernel
lib
LICENSES
mm
net
rust
samples
scripts
security
sound
tools
usr
virt
.clang-format
.cocciconfig
.editorconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
.rustfmt.toml
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS
Makefile
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 reStructuredText 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.