Console: switching to colour VGA+ 80x25 ================================================================== BUG: KASAN: slab-out-of-bounds in scr_memcpyw include/linux/vt_buffer.h:38 [inline] BUG: KASAN: slab-out-of-bounds in fbcon_prepare_logo+0x94e/0xc60 drivers/video/fbdev/core/fbcon.c:646 Read of size 26 at addr ffff88802c863dea by task syz.3.19625/25219 CPU: 1 UID: 0 PID: 25219 Comm: syz.3.19625 Tainted: G U W I L XTNJ syzkaller #0 PREEMPT(full) Tainted: [U]=USER, [W]=WARN, [I]=FIRMWARE_WORKAROUND, [L]=SOFTLOCKUP, [X]=AUX, [T]=RANDSTRUCT, [N]=TEST, [J]=FWCTL Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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+0x156/0x4c9 mm/kasan/report.c:482 kasan_report+0xdf/0x1e0 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:646 fbcon_init+0x10a0/0x1820 drivers/video/fbdev/core/fbcon.c:1180 visual_init+0x320/0x620 drivers/tty/vt/vt.c:1014 do_bind_con_driver.isra.0+0x636/0x9c0 drivers/tty/vt/vt.c:3954 vt_bind drivers/tty/vt/vt.c:4110 [inline] store_bind+0x609/0x730 drivers/tty/vt/vt.c:4182 dev_attr_store+0x58/0x80 drivers/base/core.c:2437 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:142 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1070 fs/read_write.c:688 ksys_write+0x12a/0x250 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe5cf19c799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe5d0051028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe5cf415fa0 RCX: 00007fe5cf19c799 RDX: 0000000000000084 RSI: 0000200000000040 RDI: 0000000000000003 RBP: 00007fe5cf232c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe5cf416038 R14: 00007fe5cf415fa0 R15: 00007ffefc437498 Allocated by task 18220: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 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:5260 [inline] __kmalloc_node_noprof+0x307/0x850 mm/slub.c:5266 kmalloc_node_noprof include/linux/slab.h:1081 [inline] alloc_slab_obj_exts+0xae/0x260 mm/slub.c:2167 __memcg_slab_post_alloc_hook+0x246/0x990 mm/memcontrol.c:3234 memcg_slab_post_alloc_hook mm/slub.c:2457 [inline] slab_post_alloc_hook mm/slub.c:4549 [inline] slab_alloc_node mm/slub.c:4866 [inline] kmem_cache_alloc_noprof+0x58a/0x6e0 mm/slub.c:4873 alloc_buffer_head+0x21/0x140 fs/buffer.c:3026 folio_alloc_buffers+0x2a0/0x8f0 fs/buffer.c:932 create_empty_buffers+0x3a/0x660 fs/buffer.c:1688 folio_create_buffers+0x13b/0x1a0 fs/buffer.c:1799 __block_write_full_folio+0xed/0xee0 fs/buffer.c:1844 block_write_full_folio+0x3b5/0x4e0 fs/buffer.c:2750 blkdev_writepages+0xc7/0x150 block/fops.c:486 do_writepages+0x278/0x600 mm/page-writeback.c:2554 __writeback_single_inode+0x164/0x13c0 fs/fs-writeback.c:1750 writeback_sb_inodes+0x766/0x1c70 fs/fs-writeback.c:2042 __writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2118 wb_writeback+0x755/0xbe0 fs/fs-writeback.c:2229 wb_check_background_flush fs/fs-writeback.c:2299 [inline] wb_do_writeback fs/fs-writeback.c:2387 [inline] wb_workfn+0x74d/0xc00 fs/fs-writeback.c:2414 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276 process_scheduled_works kernel/workqueue.c:3359 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 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 object at ffff88802c863d00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 98 bytes to the right of allocated 136-byte region [ffff88802c863d00, ffff88802c863d88) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802c863e00 pfn:0x2c863 flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000200 ffff88813fe3c3c0 ffff88813fe37288 ffffea0000b05810 raw: ffff88802c863e00 000000080010000e 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 13522, tgid 13519 (syz.1.16559), ts 1145295906587, free_ts 1144591259513 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5250 alloc_slab_page mm/slub.c:3292 [inline] allocate_slab mm/slub.c:3481 [inline] new_slab+0xa6/0x6b0 mm/slub.c:3539 refill_objects+0x26b/0x400 mm/slub.c:7175 refill_sheaf mm/slub.c:2812 [inline] __pcs_replace_empty_main+0x1ab/0x660 mm/slub.c:4615 alloc_from_pcs mm/slub.c:4717 [inline] slab_alloc_node mm/slub.c:4851 [inline] __do_kmalloc_node mm/slub.c:5259 [inline] __kmalloc_node_track_caller_noprof+0x694/0x850 mm/slub.c:5368 kmemdup_noprof+0x29/0x60 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:763 [inline] neigh_parms_alloc+0x85/0x5e0 net/core/neighbour.c:1773 inetdev_init+0x13c/0x570 net/ipv4/devinet.c:280 inetdev_event+0x7fa/0x17f0 net/ipv4/devinet.c:1590 notifier_call_chain+0x99/0x420 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2249 call_netdevice_notifiers_extack net/core/dev.c:2287 [inline] call_netdevice_notifiers net/core/dev.c:2301 [inline] register_netdevice+0x16e6/0x2210 net/core/dev.c:11462 __ip_tunnel_create+0x52b/0x670 net/ipv4/ip_tunnel.c:268 ip_tunnel_init_net+0x230/0x780 net/ipv4/ip_tunnel.c:1147 page last free pid 13517 tgid 13517 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0x7e1/0x10d0 mm/page_alloc.c:2978 free_image_page kernel/power/snapshot.c:267 [inline] free_zone_bm_rtree kernel/power/snapshot.c:585 [inline] memory_bm_free+0x139/0x340 kernel/power/snapshot.c:732 free_basic_memory_bitmaps+0x58/0xd0 kernel/power/snapshot.c:1178 snapshot_release+0x197/0x1f0 kernel/power/user.c:123 __fput+0x3ff/0xb40 fs/file_table.c:469 task_work_run+0x150/0x240 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x668/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802c863c80: 00 00 00 04 fc fc fc fc fc fc fc fc fc fc fc fc ffff88802c863d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88802c863d80: 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88802c863e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802c863e80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================