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Thomas Zimmermann 5247a8b313 drm/bochs: Do not put DRM device in PCI remove callback
Removing the bochs PCI device should mark the DRM device as unplugged
without removing it. Hence clear the respective call to drm_dev_put()
from bochs_pci_remove().

Fixes a double unref in devm_drm_dev_init_release(). An example error
message is shown below:

[   32.958338] BUG: KASAN: use-after-free in drm_dev_put.part.0+0x1b/0x90
[   32.958850] Write of size 4 at addr ffff888152134004 by task (udev-worker)/591
[   32.959574] CPU: 3 UID: 0 PID: 591 Comm: (udev-worker) Tainted: G            E      6.13.0-rc2-1-default+ #3417
[   32.960316] Tainted: [E]=UNSIGNED_MODULE
[   32.960637] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-2-gc13ff2cd-prebuilt.qemu.org 04/01/2014
[   32.961429] Call Trace:
[   32.961433]  <TASK>
[   32.961439]  dump_stack_lvl+0x68/0x90
[   32.961452]  print_address_description.constprop.0+0x88/0x330
[   32.961461]  ? preempt_count_sub+0x14/0xc0
[   32.961473]  print_report+0xe2/0x1d0
[   32.961479]  ? srso_alias_return_thunk+0x5/0xfbef5
[   32.963725]  ? __virt_addr_valid+0x143/0x320
[   32.964077]  ? srso_alias_return_thunk+0x5/0xfbef5
[   32.964463]  ? drm_dev_put.part.0+0x1b/0x90
[   32.964817]  kasan_report+0xce/0x1a0
[   32.965123]  ? drm_dev_put.part.0+0x1b/0x90
[   32.965474]  kasan_check_range+0xff/0x1c0
[   32.965806]  drm_dev_put.part.0+0x1b/0x90
[   32.966138]  release_nodes+0x84/0xc0
[   32.966447]  devres_release_all+0xd2/0x110
[   32.966788]  ? __pfx_devres_release_all+0x10/0x10
[   32.967177]  ? preempt_count_sub+0x14/0xc0
[   32.967523]  device_unbind_cleanup+0x16/0xc0
[   32.967886]  really_probe+0x1b7/0x570
[   32.968207]  __driver_probe_device+0xca/0x1b0
[   32.968568]  driver_probe_device+0x4a/0xf0
[   32.968907]  __driver_attach+0x10b/0x290
[   32.969239]  ? __pfx___driver_attach+0x10/0x10
[   32.969598]  bus_for_each_dev+0xc0/0x110
[   32.969923]  ? __pfx_bus_for_each_dev+0x10/0x10
[   32.970291]  ? bus_add_driver+0x17a/0x2b0
[   32.970622]  ? srso_alias_return_thunk+0x5/0xfbef5
[   32.971011]  bus_add_driver+0x19a/0x2b0
[   32.971335]  driver_register+0xd8/0x160
[   32.971671]  ? __pfx_bochs_pci_driver_init+0x10/0x10 [bochs]
[   32.972130]  do_one_initcall+0xba/0x390
[...]

After unplugging the DRM device, clients will close their references.
Closing the final reference will also release the DRM device.

Reported-by: Dr. David Alan Gilbert <dave@treblig.org>
Closes: https://lore.kernel.org/lkml/Z18dbfDAiFadsSdg@gallifrey/
Fixes: 04826f5886 ("drm/bochs: Allocate DRM device in struct bochs_device")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: virtualization@lists.linux.dev
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20250103095615.231162-1-tzimmermann@suse.de
2025-01-23 07:37:29 +01:00
arch fbdev: Fix recursive dependencies wrt BACKLIGHT_CLASS_DEVICE 2024-12-17 18:06:10 +01:00
block block-6.13-20242901 2024-11-30 15:47:29 -08:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto Random number generator updates for Linux 6.13-rc1. 2024-11-19 10:43:44 -08:00
Documentation dt-bindings: display: adi,adv7533: Drop single lane support 2024-12-20 03:53:25 +02:00
drivers drm/bochs: Do not put DRM device in PCI remove callback 2025-01-23 07:37:29 +01:00
fs This pull request contains the following changes for UML: 2024-11-30 10:34:54 -08:00
include Merge tag 'drm-misc-fixes-2024-12-05' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes 2024-12-06 08:40:47 +10:00
init - The series "resource: A couple of cleanups" from Andy Shevchenko 2024-11-25 16:09:48 -08:00
io_uring io_uring-6.13-20242901 2024-11-30 15:43:02 -08:00
ipc - The series "resource: A couple of cleanups" from Andy Shevchenko 2024-11-25 16:09:48 -08:00
kernel - Fix a case where posix timers with a thread-group-wide target would miss 2024-12-01 12:41:21 -08:00
lib vsnprintf: Removal of bprintf() 2024-12-01 13:10:51 -08:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm Kbuild updates for v6.13 2024-11-30 13:41:50 -08:00
net 9p update for 6.13-rc1 2024-11-30 10:28:14 -08:00
rust block-6.13-20242901 2024-11-30 15:47:29 -08:00
samples TTY / Serial driver updates for 6.13-rc1 2024-11-30 09:03:16 -08:00
scripts Kbuild updates for v6.13 2024-11-30 13:41:50 -08:00
security lsm/stable-6.13 PR 20241129 2024-11-30 18:14:56 -08:00
sound sound fixes for 6.13-rc1 2024-11-29 13:01:05 -08:00
tools turbostat version 2024.11.30 2024-11-30 18:30:22 -08:00
usr initramfs: shorten cmd_initfs in usr/Makefile 2024-07-16 01:07:52 +09:00
virt VFIO updates for v6.13 2024-11-27 12:57:03 -08:00
.clang-format clang-format: Update with v6.11-rc1's for_each macro list 2024-08-02 13:20:31 +02:00
.clippy.toml rust: enable Clippy's check-private-items 2024-10-07 21:39:57 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Kbuild updates for v6.13 2024-11-30 13:41:50 -08:00
.mailmap media updates for v6.13-rc1 2024-11-20 14:01:15 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS cgroup: Changes for v6.13 2024-11-20 09:54:49 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: align Danilo's maintainer entries 2024-12-10 23:56:37 +01:00
Makefile Linux 6.13-rc1 2024-12-01 14:28:56 -08:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

Linux kernel
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Please read the Documentation/process/changes.rst file, as it contains the
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