Gaosheng Cui e83b47580a lib/fonts: fix undefined behavior in bit shift for get_default_font ... [ Upstream commit 6fe888c4d2 ] 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> Link: https://lkml.kernel.org/r/20221031113829.4183153-1-cuigaosheng1@huawei.com Fixes: c81f717cb9 ("fbcon: Fix typo and bogus logic in get_default_font") Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-12-31 13:14:02 +01:00
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Kconfig	…
Makefile	…
font_6x8.c	…
font_6x10.c	…
font_6x11.c	…
font_7x14.c	…
font_8x8.c	…
font_8x16.c	…
font_10x18.c	…
font_acorn_8x8.c	…
font_mini_4x6.c	…
font_pearl_8x8.c	…
font_sun8x16.c	…
font_sun12x22.c	…
font_ter16x32.c	…
fonts.c	lib/fonts: fix undefined behavior in bit shift for get_default_font	2022-12-31 13:14:02 +01:00