================================================================== BUG: KASAN: global-out-of-bounds in __fb_pad_aligned_buffer include/linux/fb.h:641 [inline] BUG: KASAN: global-out-of-bounds in bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:95 [inline] BUG: KASAN: global-out-of-bounds in bit_putcs+0xa63/0xde0 drivers/video/fbdev/core/bitblit.c:184 Read of size 1 at addr ffffffff8c187a70 by task syz.4.1221/9348 CPU: 1 UID: 0 PID: 9348 Comm: syz.4.1221 Not tainted 6.16.0-rc2-syzkaller-00231-g75f5f23f8787 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xcd/0x680 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 __fb_pad_aligned_buffer include/linux/fb.h:641 [inline] bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:95 [inline] bit_putcs+0xa63/0xde0 drivers/video/fbdev/core/bitblit.c:184 fbcon_putcs+0x383/0x4a0 drivers/video/fbdev/core/fbcon.c:1314 con_flush drivers/tty/vt/vt.c:2746 [inline] do_con_write+0xff0/0x8280 drivers/tty/vt/vt.c:3173 con_write+0x23/0xb0 drivers/tty/vt/vt.c:3516 process_output_block drivers/tty/n_tty.c:561 [inline] n_tty_write+0x40f/0x1160 drivers/tty/n_tty.c:2377 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write.constprop.0+0x504/0x9b0 drivers/tty/tty_io.c:1081 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x6c4/0x1150 fs/read_write.c:686 ksys_write+0x12a/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f29dff8e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f29e0d53038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f29e01b5fa0 RCX: 00007f29dff8e929 RDX: 0000000000001006 RSI: 0000200000001980 RDI: 0000000000000009 RBP: 00007f29e0010b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f29e01b5fa0 R15: 00007fff33db8d08 The buggy address belongs to the variable: type_check_kinds+0x230/0xc80 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xc187 flags: 0xfff00000002000(reserved|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000002000 ffffea00003061c8 ffffea00003061c8 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner info is not present (never set?) Memory state around the buggy address: ffffffff8c187900: 00 04 f9 f9 f9 f9 f9 f9 00 00 02 f9 f9 f9 f9 f9 ffffffff8c187980: 00 03 f9 f9 f9 f9 f9 f9 07 f9 f9 f9 f9 f9 f9 f9 >ffffffff8c187a00: 00 01 f9 f9 f9 f9 f9 f9 00 05 f9 f9 f9 f9 f9 f9 ^ ffffffff8c187a80: 03 f9 f9 f9 f9 f9 f9 f9 03 f9 f9 f9 f9 f9 f9 f9 ffffffff8c187b00: 03 f9 f9 f9 f9 f9 f9 f9 00 07 f9 f9 f9 f9 f9 f9 ==================================================================