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Thomas Zimmermann bf43e4521f drm/aperture: Run fbdev removal before internal helpers
Always run fbdev removal first to remove simpledrm via
sysfb_disable(). This clears the internal state. The later call
to drm_aperture_detach_drivers() then does nothing. Otherwise,
with drm_aperture_detach_drivers() running first, the call to
sysfb_disable() uses inconsistent state.

Example backtrace show below:

[   11.663422] ==================================================================
[   11.663426] BUG: KASAN: use-after-free in device_del+0x79/0x5f0
[   11.663435] Read of size 8 at addr ffff888108185050 by task systemd-udevd/311
[   11.663440] CPU: 0 PID: 311 Comm: systemd-udevd Tainted: G            E     5
	.19.0-rc2-1-default+ #1689
[   11.663445] Hardware name: HP ProLiant DL120 G7, BIOS J01 04/21/2011
[   11.663447] Call Trace:
[   11.663449]  <TASK>
[   11.663451]  ? device_del+0x79/0x5f0
[   11.663456]  dump_stack_lvl+0x5b/0x73
[   11.663462]  print_address_description.constprop.0+0x1f/0x1b0
[   11.663468]  ? device_del+0x79/0x5f0
[   11.663471]  ? device_del+0x79/0x5f0
[   11.663475]  print_report.cold+0x3c/0x21c
[   11.663481]  ? lock_acquired+0x87/0x1e0
[   11.663484]  ? lock_acquired+0x87/0x1e0
[   11.663489]  ? device_del+0x79/0x5f0
[   11.663492]  kasan_report+0xbf/0xf0
[   11.663498]  ? device_del+0x79/0x5f0
[   11.663503]  device_del+0x79/0x5f0
[   11.663509]  ? device_remove_attrs+0x170/0x170
[   11.663514]  ? lock_is_held_type+0xe8/0x140
[   11.663523]  platform_device_del.part.0+0x19/0xe0
[   11.663530]  platform_device_unregister+0x1c/0x30
[   11.663535]  sysfb_disable+0x2d/0x70
[   11.663540]  remove_conflicting_framebuffers+0x1c/0xf0
[   11.663546]  remove_conflicting_pci_framebuffers+0x130/0x1a0
[   11.663554]  drm_aperture_remove_conflicting_pci_framebuffers+0x86/0xb0
[   11.663561]  ? mgag200_pci_remove+0x30/0x30 [mgag200]
[   11.663578]  mgag200_pci_probe+0x2d/0x140 [mgag200]

Reported-by: Zack Rusin <zackr@vmware.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
Fixes: ee7a69aa38 ("fbdev: Disable sysfb device registration when removing conflicting FBs")
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Changcheng Deng <deng.changcheng@zte.com.cn>
Link: https://patchwork.freedesktop.org/patch/msgid/20220617121027.30273-1-tzimmermann@suse.de
(cherry picked from commit fb84efa28a)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
2022-07-04 13:35:08 +02:00
arch Hot fixes for 5.19-rc1. 2022-06-05 17:05:38 -07:00
block for-5.19/drivers-2022-06-02 2022-06-03 10:25:56 -07:00
certs Kbuild updates for v5.19 2022-05-26 12:09:50 -07:00
crypto This update includes the following changes: 2022-05-27 18:06:49 -07:00
Documentation firmware: sysfb: Add sysfb_disable() helper function 2022-06-29 09:51:41 +02:00
drivers drm/aperture: Run fbdev removal before internal helpers 2022-07-04 13:35:08 +02:00
fs fix for breakage in #work.fd this window 2022-06-05 17:14:03 -07:00
include firmware: sysfb: Add sysfb_disable() helper function 2022-06-29 09:51:41 +02:00
init This set of changes updates init and user mode helper tasks to be 2022-06-03 16:03:05 -07:00
ipc These changes update the ipc sysctls so that they are fundamentally 2022-06-03 15:54:57 -07:00
kernel A single featurelet for delay accounting. Delayed a bit 2022-06-05 16:58:27 -07:00
lib Bitmap patches for 5.19-rc1 2022-06-04 14:04:27 -07:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm Hot fixes for 5.19-rc1. 2022-06-05 17:05:38 -07:00
net bluetooth: don't use bitmaps for random flag accesses 2022-06-05 16:28:41 -07:00
samples drm for 5.19-rc1 2022-05-25 16:18:27 -07:00
scripts A set of objtool fixes: 2022-06-05 09:45:27 -07:00
security Cleanups (and one fix) around struct mount handling. 2022-06-04 19:00:05 -07:00
sound USB / Thunderbolt changes for 5.19-rc1 2022-06-03 11:17:49 -07:00
tools A single featurelet for delay accounting. Delayed a bit 2022-06-05 16:58:27 -07:00
usr Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
virt VFIO updates for v5.19-rc1 2022-06-01 13:49:15 -07:00
.clang-format clang-format: Fix space after for_each macros 2022-05-20 19:27:16 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.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 kbuild: split the second line of *.mod into *.usyms 2022-05-08 03:16:59 +09:00
.mailmap Hot fixes for 5.19-rc1. 2022-06-05 17:05:38 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: replace a Microchip AT91 maintainer 2022-02-09 11:30:01 +01:00
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 Hot fixes for 5.19-rc1. 2022-06-05 17:05:38 -07:00
Makefile Linux 5.19-rc1 2022-06-05 17:18:54 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -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.

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.