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BUG: KASAN: vmalloc-out-of-bounds in fast_imageblit drivers/video/fbdev/core/sysimgblt.c:229 [inline]
BUG: KASAN: vmalloc-out-of-bounds in sys_imageblit+0x1195/0x1510 drivers/video/fbdev/core/sysimgblt.c:275
Write of size 4 at addr ffffc90001d21000 by task syz-executor.5/20448

CPU: 0 PID: 20448 Comm: syz-executor.5 Not tainted 5.14.0-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:88 [inline]
 dump_stack_lvl+0x1ae/0x29f lib/dump_stack.c:105
 print_address_description+0x66/0x3b0 mm/kasan/report.c:233
 __kasan_report mm/kasan/report.c:419 [inline]
 kasan_report+0x163/0x210 mm/kasan/report.c:436
 fast_imageblit drivers/video/fbdev/core/sysimgblt.c:229 [inline]
 sys_imageblit+0x1195/0x1510 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+0x163/0x300 drivers/gpu/drm/drm_fb_helper.c:2276
 bit_putcs+0x18e8/0x1de0 drivers/video/fbdev/core/bitblit.c:105
 fbcon_putcs+0x2ae/0x430 drivers/video/fbdev/core/fbcon.c:1296
 do_update_region+0x4d6/0x6a0 drivers/tty/vt/vt.c:676
 redraw_screen+0x8f6/0x1270 drivers/tty/vt/vt.c:1035
 do_fb_ioctl+0x6d4/0x7e0 drivers/video/fbdev/core/fbmem.c:1108
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:1055
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665e9
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9022dc2188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9
RDX: 0000000020000400 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80
R13: 00007ffd9385b67f R14: 00007f9022dc2300 R15: 0000000000022000


Memory state around the buggy address:
 ffffc90001d20f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90001d20f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90001d21000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
                   ^
 ffffc90001d21080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc90001d21100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
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