================================================================== 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:686 Read of size 2 at addr ffff8880297aa45e by task syz.2.1380/13284 CPU: 0 UID: 0 PID: 13284 Comm: syz.2.1380 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 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+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1d0 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:686 fbcon_init+0x1065/0x1830 drivers/video/fbdev/core/fbcon.c:1228 visual_init+0x320/0x620 drivers/tty/vt/vt.c:1048 do_bind_con_driver.isra.0+0x636/0x9c0 drivers/tty/vt/vt.c:4056 vt_bind drivers/tty/vt/vt.c:4212 [inline] store_bind+0x609/0x730 drivers/tty/vt/vt.c:4284 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 iter_file_splice_write+0x830/0x10a0 fs/splice.c:736 do_splice_from fs/splice.c:936 [inline] direct_splice_actor+0x192/0x6c0 fs/splice.c:1159 splice_direct_to_actor+0x345/0xa30 fs/splice.c:1103 do_splice_direct_actor fs/splice.c:1202 [inline] do_splice_direct+0x174/0x240 fs/splice.c:1228 do_sendfile+0xadc/0xe20 fs/read_write.c:1372 __do_sys_sendfile64 fs/read_write.c:1433 [inline] __se_sys_sendfile64 fs/read_write.c:1419 [inline] __x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1419 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x840 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff57d99ce59 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:00007ff57e817028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007ff57dc16180 RCX: 00007ff57d99ce59 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005 RBP: 00007ff57da32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000000a R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff57dc16218 R14: 00007ff57dc16180 R15: 00007ffca6d56da8 Allocated by task 5003: 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:5296 [inline] __kmalloc_node_track_caller_noprof+0x304/0x850 mm/slub.c:5408 kmemdup_noprof+0x29/0x60 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:763 [inline] shmem_symlink+0x28d/0xa00 mm/shmem.c:4109 vfs_symlink fs/namei.c:5643 [inline] vfs_symlink+0x178/0x4d0 fs/namei.c:5622 filename_symlinkat+0x2a6/0x560 fs/namei.c:5668 __do_sys_symlink fs/namei.c:5695 [inline] __se_sys_symlink fs/namei.c:5691 [inline] __x64_sys_symlink+0x79/0xb0 fs/namei.c:5691 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x840 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880297aa440 which belongs to the cache kmalloc-16 of size 16 The buggy address is located 21 bytes to the right of allocated 9-byte region [ffff8880297aa440, ffff8880297aa449) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x297aa flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88813fe30640 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800800080 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 48, tgid 48 (kworker/u8:3), ts 8232937498, free_ts 7210006442 create_dummy_stack mm/page_owner.c:103 [inline] register_dummy_stack+0x74/0xb0 mm/page_owner.c:109 init_page_owner+0x42/0xa10 mm/page_owner.c:127 invoke_init_callbacks mm/page_ext.c:152 [inline] page_ext_init+0x71d/0x780 mm/page_ext.c:490 mm_core_init+0x229/0x270 mm/mm_init.c:2738 page last free pid 24 tgid 24 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1397 [inline] __free_frozen_pages+0x794/0x10a0 mm/page_alloc.c:2938 vfree mm/vmalloc.c:3472 [inline] vfree+0x15f/0x8d0 mm/vmalloc.c:3436 delayed_vfree_work+0x56/0x80 mm/vmalloc.c:3392 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314 process_scheduled_works kernel/workqueue.c:3397 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff8880297aa300: 00 03 fc fc 00 00 fc fc 00 00 fc fc 00 00 fc fc ffff8880297aa380: 00 03 fc fc 00 03 fc fc 00 03 fc fc 00 03 fc fc >ffff8880297aa400: 00 00 fc fc 00 04 fc fc 00 01 fc fc 00 00 fc fc ^ ffff8880297aa480: 00 00 fc fc 00 04 fc fc 00 01 fc fc 00 01 fc fc ffff8880297aa500: 00 01 fc fc 00 01 fc fc 00 00 fc fc fa fb fc fc ==================================================================