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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+0x1e04/0x2740 drivers/video/fbdev/core/sysimgblt.c:323
Write of size 4 at addr ffffc90003dec000 by task syz-executor.1/14083

CPU: 0 PID: 14083 Comm: syz-executor.1 Not tainted 6.0.0-rc1-syzkaller-00340-g50cd95ac4654 #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+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description+0x65/0x4b0 mm/kasan/report.c:317
 print_report+0x108/0x220 mm/kasan/report.c:433
 kasan_report+0xfb/0x130 mm/kasan/report.c:495
 fast_imageblit drivers/video/fbdev/core/sysimgblt.c:257 [inline]
 sys_imageblit+0x1e04/0x2740 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+0x163/0x300 drivers/gpu/drm/drm_fb_helper.c:2340
 bit_putcs+0x19b9/0x1ed0
 fbcon_putcs+0x347/0x520 drivers/video/fbdev/core/fbcon.c:1287
 do_update_region+0x530/0x740 drivers/tty/vt/vt.c:676
 invert_screen+0x48e/0xef0 drivers/tty/vt/vt.c:800
 highlight drivers/tty/vt/selection.c:57 [inline]
 clear_selection+0x55/0x70 drivers/tty/vt/selection.c:85
 vc_do_resize+0x724/0x18c0 drivers/tty/vt/vt.c:1257
 fbcon_do_set_font+0xac5/0x1330 drivers/video/fbdev/core/fbcon.c:2428
 fbcon_set_font+0xc29/0xf70 drivers/video/fbdev/core/fbcon.c:2519
 con_font_set drivers/tty/vt/vt.c:4666 [inline]
 con_font_op+0xbe8/0x1070 drivers/tty/vt/vt.c:4710
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x172e/0x1d00 drivers/tty/vt/vt_ioctl.c:752
 tty_ioctl+0x874/0xc60 drivers/tty/tty_io.c:2778
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fa575e89279
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:00007fa576fa1168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa575f9c120 RCX: 00007fa575e89279
RDX: 0000000020000440 RSI: 0000000000004b72 RDI: 0000000000000005
RBP: 00007fa575ee3189 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd64b5c1bf R14: 00007fa576fa1300 R15: 0000000000022000
 </TASK>

Memory state around the buggy address:
 ffffc90003debf00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc90003debf80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
>ffffc90003dec000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
                   ^
 ffffc90003dec080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc90003dec100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
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