Kernel sources for Moto G9 (Play) (Guamp)
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Nicholas Piggin 117777467b KVM: do not allow mapping valid but non-reference-counted pages
commit f8be156be163a052a067306417cd0ff679068c97 upstream.

It's possible to create a region which maps valid but non-refcounted
pages (e.g., tail pages of non-compound higher order allocations). These
host pages can then be returned by gfn_to_page, gfn_to_pfn, etc., family
of APIs, which take a reference to the page, which takes it from 0 to 1.
When the reference is dropped, this will free the page incorrectly.

Fix this by only taking a reference on valid pages if it was non-zero,
which indicates it is participating in normal refcounting (and can be
released with put_page).

This addresses CVE-2021-22543.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-28 11:13:51 +02:00
arch nds32: fix up stack guard gap 2021-07-28 11:13:51 +02:00
block blk-wbt: make sure throttle is enabled properly 2021-07-20 16:15:48 +02:00
certs certs: Fix blacklist flag type confusion 2021-03-04 09:39:44 +01:00
crypto crypto: shash - avoid comparing pointers to exported functions under CFI 2021-07-20 16:15:44 +02:00
Documentation clocksource: Retry clock read if long delays detected 2021-07-20 16:15:46 +02:00
drivers drm: Return -ENOTTY for non-drm ioctls 2021-07-28 11:13:51 +02:00
firmware Fix built-in early-load Intel microcode alignment 2020-01-23 08:21:29 +01:00
fs proc: Avoid mixing integer types in mem_rw() 2021-07-28 11:13:49 +02:00
include drm: Return -ENOTTY for non-drm ioctls 2021-07-28 11:13:51 +02:00
init pid: take a reference when initializing cad_pid 2021-06-10 13:24:06 +02:00
ipc ipc/util.c: sysvipc_find_ipc() incorrectly updates position index 2020-05-20 08:18:40 +02:00
kernel tracing: Fix bug in rb_per_cpu_empty() that might cause deadloop. 2021-07-28 11:13:50 +02:00
lib lib/decompress_unlz4.c: correctly handle zero-padding around initrds. 2021-07-20 16:16:10 +02:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm: slab: fix kmem_cache_create failed when sysfs node not destroyed 2021-07-28 11:13:44 +02:00
net net: sched: cls_api: Fix the the wrong parameter 2021-07-28 11:13:49 +02:00
samples samples/bpf: Fix the error return code of xdp_redirect's main() 2021-07-20 16:15:51 +02:00
scripts kbuild: mkcompile_h: consider timestamp if KBUILD_BUILD_TIMESTAMP is set 2021-07-28 11:13:43 +02:00
security smackfs: restrict bytes count in smk_set_cipso() 2021-07-20 16:16:06 +02:00
sound ALSA: sb: Fix potential ABBA deadlock in CSP driver 2021-07-28 11:13:49 +02:00
tools selftest: use mmap instead of posix_memalign to allocate memory 2021-07-28 11:13:51 +02:00
usr initramfs: restore default compression behavior 2020-04-13 10:44:59 +02:00
virt KVM: do not allow mapping valid but non-reference-counted pages 2021-07-28 11:13:51 +02:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS Documentation/llvm: add documentation on building w/ Clang/LLVM 2020-09-26 18:01:31 +02:00
Makefile Linux 4.19.198 2021-07-20 16:16:16 +02:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

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.
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.