[drm] Initialized gud 1.0.0 for 1-1:1.0 on minor 1 ================================================================== BUG: KASAN: use-after-free in scr_memcpyw include/linux/vt_buffer.h:38 [inline] BUG: KASAN: use-after-free in fbcon_prepare_logo+0x94e/0xc60 drivers/video/fbdev/core/fbcon.c:685 Read of size 256 at addr ffff888040f8bfe0 by task kworker/1:4/13579 CPU: 1 UID: 0 PID: 13579 Comm: kworker/1:4 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:186 [inline] kasan_check_range+0x10f/0x1e0 mm/kasan/generic.c:200 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105 scr_memcpyw include/linux/vt_buffer.h:38 [inline] fbcon_prepare_logo+0x94e/0xc60 drivers/video/fbdev/core/fbcon.c:685 fbcon_init+0x1065/0x1830 drivers/video/fbdev/core/fbcon.c:1227 visual_init+0x320/0x620 drivers/tty/vt/vt.c:1048 do_bind_con_driver.isra.0+0x636/0x9c0 drivers/tty/vt/vt.c:4054 do_take_over_console+0x501/0x5d0 drivers/tty/vt/vt.c:4594 do_fbcon_takeover+0xe9/0x210 drivers/video/fbdev/core/fbcon.c:620 do_fb_registered drivers/video/fbdev/core/fbcon.c:3007 [inline] fbcon_fb_registered+0x364/0x4b0 drivers/video/fbdev/core/fbcon.c:3031 do_register_framebuffer+0x503/0x870 drivers/video/fbdev/core/fbmem.c:538 register_framebuffer+0x23/0x40 drivers/video/fbdev/core/fbmem.c:605 __drm_fb_helper_initial_config_and_unlock+0xf3b/0x17f0 drivers/gpu/drm/drm_fb_helper.c:1746 drm_fb_helper_initial_config drivers/gpu/drm/drm_fb_helper.c:1808 [inline] drm_fb_helper_initial_config+0x44/0x60 drivers/gpu/drm/drm_fb_helper.c:1800 drm_fbdev_client_hotplug+0x19e/0x220 drivers/gpu/drm/clients/drm_fbdev_client.c:66 drm_client_register+0x197/0x280 drivers/gpu/drm/drm_client.c:143 drm_fbdev_client_setup+0x155/0x480 drivers/gpu/drm/clients/drm_fbdev_client.c:168 drm_client_setup drivers/gpu/drm/clients/drm_client_setup.c:46 [inline] drm_client_setup+0x160/0x1a0 drivers/gpu/drm/clients/drm_client_setup.c:35 gud_probe+0x1835/0x1c20 drivers/gpu/drm/gud/gud_drv.c:653 usb_probe_interface+0x386/0x9b0 drivers/usb/core/driver.c:399 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:706 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x64/0x160 drivers/base/bus.c:620 device_add+0x121d/0x1970 drivers/base/core.c:3776 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:706 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x64/0x160 drivers/base/bus.c:620 device_add+0x121d/0x1970 drivers/base/core.c:3776 usb_new_device.part.0+0xcc2/0x1686 drivers/usb/core/hub.c:2708 usb_new_device include/linux/workqueue.h:715 [inline] hub_port_connect drivers/usb/core/hub.c:5580 [inline] hub_port_connect_change drivers/usb/core/hub.c:5720 [inline] port_event drivers/usb/core/hub.c:5884 [inline] hub_event.cold+0x1e3/0xe90 drivers/usb/core/hub.c:5966 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3387 process_scheduled_works kernel/workqueue.c:3470 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3551 kthread+0x373/0x450 kernel/kthread.c:436 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x40f8b flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 ffffea000103e288 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 2, migratetype Unmovable, gfp_mask 0x92820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC), pid 13579, tgid 13579 (kworker/1:4), ts 783133288306 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x110d/0x35d0 mm/page_alloc.c:3943 __alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436 alloc_pages_mpol+0x201/0x550 mm/mempolicy.c:2486 alloc_pages_noprof+0x1a/0x160 mm/mempolicy.c:2577 stack_depot_save_flags+0x914/0x9f0 lib/stackdepot.c:685 kasan_save_stack+0x3f/0x50 mm/kasan/common.c:58 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5414 [inline] __kmalloc_noprof+0x32f/0x840 mm/slub.c:5439 _kmalloc_noprof include/linux/slab.h:995 [inline] _kmalloc_array_noprof include/linux/slab.h:1211 [inline] bit_cursor+0x938/0x14e0 drivers/video/fbdev/core/bitblit.c:337 fbcon_cursor+0x43c/0x5e0 drivers/video/fbdev/core/fbcon.c:1427 set_cursor drivers/tty/vt/vt.c:896 [inline] set_cursor+0x1db/0x250 drivers/tty/vt/vt.c:887 redraw_screen+0x4de/0x760 drivers/tty/vt/vt.c:1010 vc_do_resize+0xc3d/0xeb0 drivers/tty/vt/vt.c:1309 vc_resize include/linux/vt_kern.h:49 [inline] fbcon_init+0x1041/0x1830 drivers/video/fbdev/core/fbcon.c:1224 page last free pid 13579 tgid 13579 ts 783133345145 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] __free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962 stack_depot_save_flags+0x456/0x9f0 lib/stackdepot.c:735 kasan_save_stack+0x3f/0x50 mm/kasan/common.c:58 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5414 [inline] __kmalloc_noprof+0x32f/0x840 mm/slub.c:5439 _kmalloc_noprof include/linux/slab.h:995 [inline] _kmalloc_array_noprof include/linux/slab.h:1211 [inline] bit_cursor+0x938/0x14e0 drivers/video/fbdev/core/bitblit.c:337 fbcon_cursor+0x43c/0x5e0 drivers/video/fbdev/core/fbcon.c:1427 set_cursor drivers/tty/vt/vt.c:896 [inline] set_cursor+0x1db/0x250 drivers/tty/vt/vt.c:887 redraw_screen+0x4de/0x760 drivers/tty/vt/vt.c:1010 vc_do_resize+0xc3d/0xeb0 drivers/tty/vt/vt.c:1309 vc_resize include/linux/vt_kern.h:49 [inline] fbcon_init+0x1041/0x1830 drivers/video/fbdev/core/fbcon.c:1224 visual_init+0x320/0x620 drivers/tty/vt/vt.c:1048 do_bind_con_driver.isra.0+0x636/0x9c0 drivers/tty/vt/vt.c:4054 do_take_over_console+0x501/0x5d0 drivers/tty/vt/vt.c:4594 do_fbcon_takeover+0xe9/0x210 drivers/video/fbdev/core/fbcon.c:620 Memory state around the buggy address: ffff888040f8be80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888040f8bf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888040f8bf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888040f8c000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888040f8c080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================