diff options
author | Thomas Zimmermann <tzimmermann@suse.de> | 2022-06-17 15:10:27 +0300 |
---|---|---|
committer | Thomas Zimmermann <tzimmermann@suse.de> | 2022-07-04 14:35:08 +0300 |
commit | bf43e4521ff3223a613f3a496991a22a4d78e04b (patch) | |
tree | 4bc168ed7fb447edf4337cf68e0f465afc3e3fbb /drivers/gpu | |
parent | 144248515246e52a3706de1ee928af29a63794b8 (diff) |
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: ee7a69aa38d8 ("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 fb84efa28a48e30b87fa1122e8aab8016c7347cd)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Diffstat (limited to 'drivers/gpu')
-rw-r--r-- | drivers/gpu/drm/drm_aperture.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/drivers/gpu/drm/drm_aperture.c b/drivers/gpu/drm/drm_aperture.c index 74bd4a76b253..059fd71424f6 100644 --- a/drivers/gpu/drm/drm_aperture.c +++ b/drivers/gpu/drm/drm_aperture.c @@ -329,7 +329,20 @@ int drm_aperture_remove_conflicting_pci_framebuffers(struct pci_dev *pdev, const struct drm_driver *req_driver) { resource_size_t base, size; - int bar, ret = 0; + int bar, ret; + + /* + * WARNING: Apparently we must kick fbdev drivers before vgacon, + * otherwise the vga fbdev driver falls over. + */ +#if IS_REACHABLE(CONFIG_FB) + ret = remove_conflicting_pci_framebuffers(pdev, req_driver->name); + if (ret) + return ret; +#endif + ret = vga_remove_vgacon(pdev); + if (ret) + return ret; for (bar = 0; bar < PCI_STD_NUM_BARS; ++bar) { if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) @@ -339,15 +352,6 @@ int drm_aperture_remove_conflicting_pci_framebuffers(struct pci_dev *pdev, drm_aperture_detach_drivers(base, size); } - /* - * WARNING: Apparently we must kick fbdev drivers before vgacon, - * otherwise the vga fbdev driver falls over. - */ -#if IS_REACHABLE(CONFIG_FB) - ret = remove_conflicting_pci_framebuffers(pdev, req_driver->name); -#endif - if (ret == 0) - ret = vga_remove_vgacon(pdev); - return ret; + return 0; } EXPORT_SYMBOL(drm_aperture_remove_conflicting_pci_framebuffers); |