sch_tbf: burst 0 is lower than device lo mtu (65550) !
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BUG: KASAN: vmalloc-out-of-bounds in fb_write_offset drivers/video/fbdev/core/sysmem.h:30 [inline]
BUG: KASAN: vmalloc-out-of-bounds in fb_bitmap_2ppw drivers/video/fbdev/core/fb_imageblit.h:364 [inline]
BUG: KASAN: vmalloc-out-of-bounds in fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:462 [inline]
BUG: KASAN: vmalloc-out-of-bounds in fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline]
BUG: KASAN: vmalloc-out-of-bounds in sys_imageblit+0x106b/0x2100 drivers/video/fbdev/core/sysimgblt.c:22
Write of size 8 at addr ffffc90002151000 by task syz.0.0/5341

CPU: 0 UID: 0 PID: 5341 Comm: syz.0.0 Not tainted 6.15.0-rc1-syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0x16e/0x5b0 mm/kasan/report.c:521
 kasan_report+0x143/0x180 mm/kasan/report.c:634
 fb_write_offset drivers/video/fbdev/core/sysmem.h:30 [inline]
 fb_bitmap_2ppw drivers/video/fbdev/core/fb_imageblit.h:364 [inline]
 fb_bitmap_imageblit drivers/video/fbdev/core/fb_imageblit.h:462 [inline]
 fb_imageblit drivers/video/fbdev/core/fb_imageblit.h:492 [inline]
 sys_imageblit+0x106b/0x2100 drivers/video/fbdev/core/sysimgblt.c:22
 drm_fbdev_shmem_defio_imageblit+0x2e/0x100 drivers/gpu/drm/drm_fbdev_shmem.c:37
 bit_putcs+0x18d3/0x1dd0 drivers/video/fbdev/core/bitblit.c:-1
 fbcon_putcs+0x2e0/0x450 drivers/video/fbdev/core/fbcon.c:1309
 do_update_region+0x39c/0x450 drivers/tty/vt/vt.c:619
 invert_screen+0x403/0xe50 drivers/tty/vt/vt.c:740
 highlight drivers/tty/vt/selection.c:57 [inline]
 clear_selection+0x59/0x80 drivers/tty/vt/selection.c:87
 vc_do_resize+0x70f/0x18b0 drivers/tty/vt/vt.c:1187
 vc_resize include/linux/vt_kern.h:49 [inline]
 fbcon_set_disp+0xac9/0x11d0 drivers/video/fbdev/core/fbcon.c:1410
 con2fb_init_display drivers/video/fbdev/core/fbcon.c:811 [inline]
 set_con2fb_map+0xb3a/0x11e0 drivers/video/fbdev/core/fbcon.c:884
 fbcon_set_con2fb_map_ioctl+0x231/0x340 drivers/video/fbdev/core/fbcon.c:3113
 do_fb_ioctl+0x3c5/0x7e0 drivers/video/fbdev/core/fb_chrdev.c:138
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f98c378d169
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f98c4654038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f98c39a5fa0 RCX: 00007f98c378d169
RDX: 00002000000000c0 RSI: 0000000000004610 RDI: 0000000000000003
RBP: 00007f98c380e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f98c39a5fa0 R15: 00007fff805801f8
 </TASK>

The buggy address belongs to the virtual mapping at
 [ffffc90001e51000, ffffc90002152000) created by:
 drm_gem_shmem_vmap+0x416/0x6d0 drivers/gpu/drm/drm_gem_shmem_helper.c:365

Memory state around the buggy address:
 ffffc90002150f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90002150f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90002151000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
                   ^
 ffffc90002151080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc90002151100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
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