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BUG: KASAN: vmalloc-out-of-bounds in fast_imageblit drivers/video/fbdev/core/sysimgblt.c:257 [inline]
BUG: KASAN: vmalloc-out-of-bounds in sys_imageblit+0x1ed0/0x2240 drivers/video/fbdev/core/sysimgblt.c:323
Write of size 4 at addr ffffc90003e855d4 by task syz-executor.0/22018

CPU: 0 PID: 22018 Comm: syz-executor.0 Not tainted 5.19.0-syzkaller-13930-g7ebfc85e2cd7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:317 [inline]
 print_report.cold+0x59/0x6e9 mm/kasan/report.c:433
 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495
 fast_imageblit drivers/video/fbdev/core/sysimgblt.c:257 [inline]
 sys_imageblit+0x1ed0/0x2240 drivers/video/fbdev/core/sysimgblt.c:323
 drm_fb_helper_sys_imageblit drivers/gpu/drm/drm_fb_helper.c:837 [inline]
 drm_fbdev_fb_imageblit+0x15c/0x350 drivers/gpu/drm/drm_fb_helper.c:2340
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:139 [inline]
 bit_putcs+0x6e1/0xd20 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x314/0x3e0 drivers/video/fbdev/core/fbcon.c:1287
 fbcon_putc+0x86/0xb0 drivers/video/fbdev/core/fbcon.c:1297
 complement_pos+0x357/0x6d0 drivers/tty/vt/vt.c:817
 highlight_pointer drivers/tty/vt/selection.c:63 [inline]
 clear_selection+0x17/0x70 drivers/tty/vt/selection.c:83
 vc_do_resize+0xe61/0x1170 drivers/tty/vt/vt.c:1257
 fbcon_do_set_font+0x43a/0x6f0 drivers/video/fbdev/core/fbcon.c:2428
 fbcon_set_font+0x89c/0xab0 drivers/video/fbdev/core/fbcon.c:2519
 con_font_set drivers/tty/vt/vt.c:4666 [inline]
 con_font_op+0x75b/0xcc0 drivers/tty/vt/vt.c:4710
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x1efa/0x2b20 drivers/tty/vt/vt_ioctl.c:752
 tty_ioctl+0xfab/0x15d0 drivers/tty/tty_io.c:2778
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fb9b9289279
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb9ba3fe168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fb9b939c050 RCX: 00007fb9b9289279
RDX: 0000000020000440 RSI: 0000000000004b72 RDI: 0000000000000005
RBP: 00007fb9b92e3189 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdf3655e7f R14: 00007fb9ba3fe300 R15: 0000000000022000
 </TASK>

Memory state around the buggy address:
 ffffc90003e85480: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc90003e85500: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
>ffffc90003e85580: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
                                                 ^
 ffffc90003e85600: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc90003e85680: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
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