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BUG: KASAN: stack-out-of-bounds in fast_imageblit drivers/video/fbdev/core/sysimgblt.c:229 [inline]
BUG: KASAN: stack-out-of-bounds in sys_imageblit+0x1182/0x1390 drivers/video/fbdev/core/sysimgblt.c:275
Write of size 4 at addr ffffc90004787d38 by task syz-executor699/4051

CPU: 1 PID: 4051 Comm: syz-executor699 Not tainted 5.16.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x57/0x7d lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0xf/0x320 mm/kasan/report.c:247
 __kasan_report mm/kasan/report.c:433 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:450
 fast_imageblit drivers/video/fbdev/core/sysimgblt.c:229 [inline]
 sys_imageblit+0x1182/0x1390 drivers/video/fbdev/core/sysimgblt.c:275
 drm_fb_helper_sys_imageblit drivers/gpu/drm/drm_fb_helper.c:794 [inline]
 drm_fbdev_fb_imageblit+0x131/0x320 drivers/gpu/drm/drm_fb_helper.c:2288
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:124 [inline]
 bit_putcs+0x647/0xc20 drivers/video/fbdev/core/bitblit.c:173
 fbcon_putcs+0x310/0x500 drivers/video/fbdev/core/fbcon.c:1277
 do_update_region+0x2dc/0x5b0 drivers/tty/vt/vt.c:676
 invert_screen+0x177/0x520 drivers/tty/vt/vt.c:800
 highlight drivers/tty/vt/selection.c:57 [inline]
 clear_selection drivers/tty/vt/selection.c:84 [inline]
 clear_selection+0x3f/0x50 drivers/tty/vt/selection.c:80
 vc_do_resize+0xc0f/0xf50 drivers/tty/vt/vt.c:1257
 fbcon_do_set_font+0x3b1/0x8a0 drivers/video/fbdev/core/fbcon.c:1928
 con_font_set drivers/tty/vt/vt.c:4666 [inline]
 con_font_op+0x5d7/0xac0 drivers/tty/vt/vt.c:4710
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline]
 vt_ioctl+0x169f/0x2120 drivers/tty/vt/vt_ioctl.c:752
 tty_ioctl+0x478/0x12d0 drivers/tty/tty_io.c:2805
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x11f/0x190 fs/ioctl.c:860
 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+0x44/0xae
RIP: 0033:0x7f8e86e07339
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc4740d3b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8e86e07339
RDX: 0000000020000000 RSI: 0000000000004b72 RDI: 0000000000000004
RBP: 00007f8e86dcb120 R08: 000000000000000d R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8e86dcb1b0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>


Memory state around the buggy address:
 ffffc90004787c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90004787c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90004787d00: 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 f3 f3 00
                                        ^
 ffffc90004787d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90004787e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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