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BUG: KASAN: global-out-of-bounds in vga_8planes_imageblit drivers/video/fbdev/vga16fb.c:1140 [inline]
BUG: KASAN: global-out-of-bounds in vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1203 [inline]
BUG: KASAN: global-out-of-bounds in vga16fb_imageblit+0x1c36/0x2210 drivers/video/fbdev/vga16fb.c:1260
Read of size 2 at addr ffffffff8899f6b8 by task syz-executor.4/16561

CPU: 1 PID: 16561 Comm: syz-executor.4 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x198/0x1fd lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x497 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 vga_8planes_imageblit drivers/video/fbdev/vga16fb.c:1140 [inline]
 vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1203 [inline]
 vga16fb_imageblit+0x1c36/0x2210 drivers/video/fbdev/vga16fb.c:1260
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:139 [inline]
 bit_putcs+0x6e1/0xd20 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x33c/0x3f0 drivers/video/fbdev/core/fbcon.c:1362
 do_update_region+0x399/0x630 drivers/tty/vt/vt.c:675
 redraw_screen+0x64e/0x770 drivers/tty/vt/vt.c:1034
 vc_do_resize+0xed8/0x1150 drivers/tty/vt/vt.c:1326
 fbcon_modechanged+0x36c/0x710 drivers/video/fbdev/core/fbcon.c:3011
 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3069
 do_fb_ioctl+0x62e/0x690 drivers/video/fbdev/core/fbmem.c:1106
 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1181
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d5b9
Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fdfa846dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000000e280 RCX: 000000000045d5b9
RDX: 00000000200001c0 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 000000000169fb6f R14: 00007fdfa846e9c0 R15: 000000000118cf4c

The buggy address belongs to the variable:
 transl_h+0x38/0x40

Memory state around the buggy address:
 ffffffff8899f580: f9 f9 f9 f9 00 00 00 00 00 00 00 00 00 00 00 00
 ffffffff8899f600: 00 00 00 00 00 00 00 00 00 00 00 f9 f9 f9 f9 f9
>ffffffff8899f680: 00 00 00 00 f9 f9 f9 f9 00 00 00 00 f9 f9 f9 f9
                                        ^
 ffffffff8899f700: 00 01 f9 f9 f9 f9 f9 f9 00 00 00 04 f9 f9 f9 f9
 ffffffff8899f780: 00 00 04 f9 f9 f9 f9 f9 00 00 00 00 00 00 02 f9
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