fbcon: Check font dimension limits
blit_x and blit_y are u32, so fbcon currently cannot support fonts larger than 32x32. The 32x32 case also needs shifting an unsigned int, to properly set bit 31, otherwise we get "UBSAN: shift-out-of-bounds in fbcon_set_font", as reported on: http://lore.kernel.org/all/IA1PR07MB98308653E259A6F2CE94A4AFABCE9@IA1PR07MB9830.namprd07.prod.outlook.com Kernel Branch: 6.2.0-rc5-next-20230124 Kernel config: https://drive.google.com/file/d/1F-LszDAizEEH0ZX0HcSR06v5q8FPl2Uv/view?usp=sharing Reproducer: https://drive.google.com/file/d/1mP1jcLBY7vWCNM60OMf-ogw-urQRjNrm/view?usp=sharingReported-by: Sanan Hasanov <sanan.hasanov@Knights.ucf.edu> Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Fixes: 2d2699d9 ("fbcon: font setting should check limitation of driver") Cc: stable@vger.kernel.org Tested-by: Miko Larsson <mikoxyzzz@gmail.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Helge Deller <deller@gmx.de>
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