In the Linux kernel, the following vulnerability has been resolved:[EOL][EOL]lib/fonts: fix undefined behavior in bit shift for get_default_font[EOL][EOL]Shifting signed 32-bit value by 31 bits is undefined, so changing[EOL]significant bit to unsigned. The UBSAN warning calltrace like below:[EOL][EOL]UBSAN: shift-out-of-bounds in lib/fonts/fonts.c:139:20[EOL]left shift of 1 by 31 places cannot be represented in type 'int'[EOL] <TASK>[EOL] dump_stack_lvl+0x7d/0xa5[EOL] dump_stack+0x15/0x1b[EOL] ubsan_epilogue+0xe/0x4e[EOL] __ubsan_handle_shift_out_of_bounds+0x1e7/0x20c[EOL] get_default_font+0x1c7/0x1f0[EOL] fbcon_startup+0x347/0x3a0[EOL] do_take_over_console+0xce/0x270[EOL] do_fbcon_takeover+0xa1/0x170[EOL] do_fb_registered+0x2a8/0x340[EOL] fbcon_fb_registered+0x47/0xe0[EOL] register_framebuffer+0x294/0x4a0[EOL] __drm_fb_helper_initial_config_and_unlock+0x43c/0x880 [drm_kms_helper][EOL] drm_fb_helper_initial_config+0x52/0x80 [drm_kms_helper][EOL] drm_fbdev_client_hotplug+0x156/0x1b0 [drm_kms_helper][EOL] drm_fbdev_generic_setup+0xfc/0x290 [drm_kms_helper][EOL] bochs_pci_probe+0x6ca/0x772 [bochs][EOL] local_pci_probe+0x4d/0xb0[EOL] pci_device_probe+0x119/0x320[EOL] really_probe+0x181/0x550[EOL] __driver_probe_device+0xc6/0x220[EOL] driver_probe_device+0x32/0x100[EOL] __driver_attach+0x195/0x200[EOL] bus_for_each_dev+0xbb/0x120[EOL] driver_attach+0x27/0x30[EOL] bus_add_driver+0x22e/0x2f0[EOL] driver_register+0xa9/0x190[EOL] __pci_register_driver+0x90/0xa0[EOL] bochs_pci_driver_init+0x52/0x1000 [bochs][EOL] do_one_initcall+0x76/0x430[EOL] do_init_module+0x61/0x28a[EOL] load_module+0x1f82/0x2e50[EOL] __do_sys_finit_module+0xf8/0x190[EOL] __x64_sys_finit_module+0x23/0x30[EOL] do_syscall_64+0x58/0x80[EOL] entry_SYSCALL_64_after_hwframe+0x63/0xcd[EOL] </TASK>