In the Linux kernel, the following vulnerability has been resolved:
fbdev: simplefb: Fix use after free in simplefb_detach_genpds()
The pm_domain cleanup can not be devres managed as it uses struct
simplefb_par which is allocated within struct fb_info by
framebuffer_alloc(). This allocation is explicitly freed by
unregister_framebuffer() in simplefb_remove().
Devres managed cleanup runs after the device remove call and thus can no
longer access struct simplefb_par.
Call simplefb_detach_genpds() explicitly from simplefb_destroy() like
the cleanup functions for clocks and regulators.
Fixes an use after free on M2 Mac mini during
aperture_remove_conflicting_devices() using the downstream asahi kernel
with Debian's kernel config. For unknown reasons this started to
consistently dereference an invalid pointer in v6.16.3 based kernels.
[ 6.736134] BUG: KASAN: slab-use-after-free in simplefb_detach_genpds+0x58/0x220
[ 6.743545] Read of size 4 at addr ffff8000304743f0 by task (udev-worker)/227
[ 6.750697]
[ 6.752182] CPU: 6 UID: 0 PID: 227 Comm: (udev-worker) Tainted: G S 6.16.3-asahi+ #16 PREEMPTLAZY
[ 6.752186] Tainted: [S]=CPU_OUT_OF_SPEC
[ 6.752187] Hardware name: Apple Mac mini (M2, 2023) (DT)
[ 6.752189] Call trace:
[ 6.752190] show_stack+0x34/0x98 (C)
[ 6.752194] dump_stack_lvl+0x60/0x80
[ 6.752197] print_report+0x17c/0x4d8
[ 6.752201] kasan_report+0xb4/0x100
[ 6.752206] __asan_report_load4_noabort+0x20/0x30
[ 6.752209] simplefb_detach_genpds+0x58/0x220
[ 6.752213] devm_action_release+0x50/0x98
[ 6.752216] release_nodes+0xd0/0x2c8
[ 6.752219] devres_release_all+0xfc/0x178
[ 6.752221] device_unbind_cleanup+0x28/0x168
[ 6.752224] device_release_driver_internal+0x34c/0x470
[ 6.752228] device_release_driver+0x20/0x38
[ 6.752231] bus_remove_device+0x1b0/0x380
[ 6.752234] device_del+0x314/0x820
[ 6.752238] platform_device_del+0x3c/0x1e8
[ 6.752242] platform_device_unregister+0x20/0x50
[ 6.752246] aperture_detach_platform_device+0x1c/0x30
[ 6.752250] aperture_detach_devices+0x16c/0x290
[ 6.752253] aperture_remove_conflicting_devices+0x34/0x50
...
[ 6.752343]
[ 6.967409] Allocated by task 62:
[ 6.970724] kasan_save_stack+0x3c/0x70
[ 6.974560] kasan_save_track+0x20/0x40
[ 6.978397] kasan_save_alloc_info+0x40/0x58
[ 6.982670] __kasan_kmalloc+0xd4/0xd8
[ 6.986420] __kmalloc_noprof+0x194/0x540
[ 6.990432] framebuffer_alloc+0xc8/0x130
[ 6.994444] simplefb_probe+0x258/0x2378
...
[ 7.054356]
[ 7.055838] Freed by task 227:
[ 7.058891] kasan_save_stack+0x3c/0x70
[ 7.062727] kasan_save_track+0x20/0x40
[ 7.066565] kasan_save_free_info+0x4c/0x80
[ 7.070751] __kasan_slab_free+0x6c/0xa0
[ 7.074675] kfree+0x10c/0x380
[ 7.077727] framebuffer_release+0x5c/0x90
[ 7.081826] simplefb_destroy+0x1b4/0x2c0
[ 7.085837] put_fb_info+0x98/0x100
[ 7.089326] unregister_framebuffer+0x178/0x320
[ 7.093861] simplefb_remove+0x3c/0x60
[ 7.097611] platform_remove+0x60/0x98
[ 7.101361] device_remove+0xb8/0x160
[ 7.105024] device_release_driver_internal+0x2fc/0x470
[ 7.110256] device_release_driver+0x20/0x38
[ 7.114529] bus_remove_device+0x1b0/0x380
[ 7.118628] device_del+0x314/0x820
[ 7.122116] platform_device_del+0x3c/0x1e8
[ 7.126302] platform_device_unregister+0x20/0x50
[ 7.131012] aperture_detach_platform_device+0x1c/0x30
[ 7.136157] aperture_detach_devices+0x16c/0x290
[ 7.140779] aperture_remove_conflicting_devices+0x34/0x50
...
Metrics
Affected Vendors & Products
| Vendors | Products |
|---|---|
| Linux |
|
No data.
No data.
References
History
Wed, 29 Oct 2025 11:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
|
| Vendors & Products |
Linux
Linux linux Kernel |
Wed, 29 Oct 2025 00:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Tue, 28 Oct 2025 12:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: fbdev: simplefb: Fix use after free in simplefb_detach_genpds() The pm_domain cleanup can not be devres managed as it uses struct simplefb_par which is allocated within struct fb_info by framebuffer_alloc(). This allocation is explicitly freed by unregister_framebuffer() in simplefb_remove(). Devres managed cleanup runs after the device remove call and thus can no longer access struct simplefb_par. Call simplefb_detach_genpds() explicitly from simplefb_destroy() like the cleanup functions for clocks and regulators. Fixes an use after free on M2 Mac mini during aperture_remove_conflicting_devices() using the downstream asahi kernel with Debian's kernel config. For unknown reasons this started to consistently dereference an invalid pointer in v6.16.3 based kernels. [ 6.736134] BUG: KASAN: slab-use-after-free in simplefb_detach_genpds+0x58/0x220 [ 6.743545] Read of size 4 at addr ffff8000304743f0 by task (udev-worker)/227 [ 6.750697] [ 6.752182] CPU: 6 UID: 0 PID: 227 Comm: (udev-worker) Tainted: G S 6.16.3-asahi+ #16 PREEMPTLAZY [ 6.752186] Tainted: [S]=CPU_OUT_OF_SPEC [ 6.752187] Hardware name: Apple Mac mini (M2, 2023) (DT) [ 6.752189] Call trace: [ 6.752190] show_stack+0x34/0x98 (C) [ 6.752194] dump_stack_lvl+0x60/0x80 [ 6.752197] print_report+0x17c/0x4d8 [ 6.752201] kasan_report+0xb4/0x100 [ 6.752206] __asan_report_load4_noabort+0x20/0x30 [ 6.752209] simplefb_detach_genpds+0x58/0x220 [ 6.752213] devm_action_release+0x50/0x98 [ 6.752216] release_nodes+0xd0/0x2c8 [ 6.752219] devres_release_all+0xfc/0x178 [ 6.752221] device_unbind_cleanup+0x28/0x168 [ 6.752224] device_release_driver_internal+0x34c/0x470 [ 6.752228] device_release_driver+0x20/0x38 [ 6.752231] bus_remove_device+0x1b0/0x380 [ 6.752234] device_del+0x314/0x820 [ 6.752238] platform_device_del+0x3c/0x1e8 [ 6.752242] platform_device_unregister+0x20/0x50 [ 6.752246] aperture_detach_platform_device+0x1c/0x30 [ 6.752250] aperture_detach_devices+0x16c/0x290 [ 6.752253] aperture_remove_conflicting_devices+0x34/0x50 ... [ 6.752343] [ 6.967409] Allocated by task 62: [ 6.970724] kasan_save_stack+0x3c/0x70 [ 6.974560] kasan_save_track+0x20/0x40 [ 6.978397] kasan_save_alloc_info+0x40/0x58 [ 6.982670] __kasan_kmalloc+0xd4/0xd8 [ 6.986420] __kmalloc_noprof+0x194/0x540 [ 6.990432] framebuffer_alloc+0xc8/0x130 [ 6.994444] simplefb_probe+0x258/0x2378 ... [ 7.054356] [ 7.055838] Freed by task 227: [ 7.058891] kasan_save_stack+0x3c/0x70 [ 7.062727] kasan_save_track+0x20/0x40 [ 7.066565] kasan_save_free_info+0x4c/0x80 [ 7.070751] __kasan_slab_free+0x6c/0xa0 [ 7.074675] kfree+0x10c/0x380 [ 7.077727] framebuffer_release+0x5c/0x90 [ 7.081826] simplefb_destroy+0x1b4/0x2c0 [ 7.085837] put_fb_info+0x98/0x100 [ 7.089326] unregister_framebuffer+0x178/0x320 [ 7.093861] simplefb_remove+0x3c/0x60 [ 7.097611] platform_remove+0x60/0x98 [ 7.101361] device_remove+0xb8/0x160 [ 7.105024] device_release_driver_internal+0x2fc/0x470 [ 7.110256] device_release_driver+0x20/0x38 [ 7.114529] bus_remove_device+0x1b0/0x380 [ 7.118628] device_del+0x314/0x820 [ 7.122116] platform_device_del+0x3c/0x1e8 [ 7.126302] platform_device_unregister+0x20/0x50 [ 7.131012] aperture_detach_platform_device+0x1c/0x30 [ 7.136157] aperture_detach_devices+0x16c/0x290 [ 7.140779] aperture_remove_conflicting_devices+0x34/0x50 ... | |
| Title | fbdev: simplefb: Fix use after free in simplefb_detach_genpds() | |
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-10-28T11:48:18.274Z
Reserved: 2025-04-16T07:20:57.153Z
Link: CVE-2025-40037
Vulnrichment
No data.
NVD
Status : Awaiting Analysis
Published: 2025-10-28T12:15:37.613
Modified: 2025-10-30T15:05:32.197
Link: CVE-2025-40037
Redhat