CVEvulnerability
CVE-2022-50511
5.5 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2025-10-07
- Last modified
- 2026-06-17
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 ([email protected])
- 5.5 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Description
In the Linux kernel, the following vulnerability has been resolved:
lib/fonts: fix undefined behavior in bit shift for get_default_font
Shifting signed 32-bit value by 31 bits is undefined, so changing
significant bit to unsigned. The UBSAN warning calltrace like below:
UBSAN: shift-out-of-bounds in lib/fonts/fonts.c:139:20
left shift of 1 by 31 places cannot be represented in type 'int'
<TASK>
dump_stack_lvl+0x7d/0xa5
dump_stack+0x15/0x1b
ubsan_epilogue+0xe/0x4e
__ubsan_handle_shift_out_of_bounds+0x1e7/0x20c
get_default_font+0x1c7/0x1f0
fbcon_startup+0x347/0x3a0
do_take_over_console+0xce/0x270
do_fbcon_takeover+0xa1/0x170
do_fb_registered+0x2a8/0x340
fbcon_fb_registered+0x47/0xe0
register_framebuffer+0x294/0x4a0
__drm_fb_helper_initial_config_and_unlock+0x43c/0x880 [drm_kms_helper]
drm_fb_helper_initial_config+0x52/0x80 [drm_kms_helper]
drm_fbdev_client_hotplug+0x156/0x1b0 [drm_kms_helper]
drm_fbdev_generic_setup+0xfc/0x290 [drm_kms_helper]
bochs_pci_probe+0x6ca/0x772 [bochs]
local_pci_probe+0x4d/0xb0
pci_device_probe+0x119/0x320
really_probe+0x181/0x550
__driver_probe_device+0xc6/0x220
driver_probe_device+0x32/0x100
__driver_attach+0x195/0x200
bus_for_each_dev+0xbb/0x120
driver_attach+0x27/0x30
bus_add_driver+0x22e/0x2f0
driver_register+0xa9/0x190
__pci_register_driver+0x90/0xa0
bochs_pci_driver_init+0x52/0x1000 [bochs]
do_one_initcall+0x76/0x430
do_init_module+0x61/0x28a
load_module+0x1f82/0x2e50
__do_sys_finit_module+0xf8/0x190
__x64_sys_finit_module+0x23/0x30
do_syscall_64+0x58/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
</TASK>
Affected configurations
• linux linux kernel (>= 2.6.23.1 < 5.4.229)
• linux linux kernel (>= 5.5 < 5.10.163)
• linux linux kernel (>= 5.11 < 5.15.86)
• linux linux kernel (>= 5.16 < 6.0.16)
• linux linux kernel (>= 6.1 < 6.1.2)
• linux linux kernel 2.6.23
References
- https://git.kernel.org/stable/c/6fe888c4d2fb174408e4540bb2d5602b9f507f90 Patch
- https://git.kernel.org/stable/c/890d91b31f4874361e0df047f57d268a7021cb12 Patch
- https://git.kernel.org/stable/c/9c14a85e18a58c102ec223144b7edb5b345c1bea Patch
- https://git.kernel.org/stable/c/c9a9aa02f0fa3318e0ae5774f404419a1b4759ca Patch
- https://git.kernel.org/stable/c/e039929e36818507e90901edae87f6fa8bc81093 Patch
- https://git.kernel.org/stable/c/e83b47580a0738361772d6f24286adfdaba57e36 Patch