================================================================== BUG: KASAN: use-after-free in scr_memcpyw include/linux/vt_buffer.h:38 [inline] BUG: KASAN: use-after-free in fbcon_prepare_logo+0xa03/0xc70 drivers/video/fbdev/core/fbcon.c:646 Read of size 256 at addr ffff8880571563c0 by task syz.1.626/9305 CPU: 0 UID: 0 PID: 9305 Comm: syz.1.626 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:194 [inline] kasan_check_range+0x100/0x1b0 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+0xa03/0xc70 drivers/video/fbdev/core/fbcon.c:646 fbcon_init+0xda0/0x1930 drivers/video/fbdev/core/fbcon.c:1179 visual_init+0x320/0x620 drivers/tty/vt/vt.c:1020 do_bind_con_driver.isra.0+0x57a/0xbf0 drivers/tty/vt/vt.c:3960 vt_bind drivers/tty/vt/vt.c:4116 [inline] store_bind+0x61d/0x760 drivers/tty/vt/vt.c:4188 dev_attr_store+0x58/0x80 drivers/base/core.c:2437 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:142 kernfs_fop_write_iter+0x3af/0x570 fs/kernfs/file.c:352 iter_file_splice_write+0xa24/0x12b0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x192/0x6c0 fs/splice.c:1161 splice_direct_to_actor+0x345/0xa30 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x174/0x240 fs/splice.c:1230 do_sendfile+0xb06/0xe50 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64 fs/read_write.c:1417 [inline] __x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7e2e98f7c9 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:00007f7e2f7b1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f7e2ebe6270 RCX: 00007f7e2e98f7c9 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000004 RBP: 00007f7e2ea13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7e2ebe6308 R14: 00007f7e2ebe6270 R15: 00007ffe7d7e5ed8 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x57156 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f0(buddy) raw: 00fff00000000000 ffffea000049d188 ffffea0000a6b108 0000000000000000 raw: 0000000000000000 0000000000000001 00000000f0000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x10cc0(GFP_KERNEL|__GFP_NORETRY), pid 7884, tgid 7883 (syz.1.357), ts 224036719298, free_ts 229921733136 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1884 prep_new_page mm/page_alloc.c:1892 [inline] get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3945 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5240 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline] alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2577 kimage_alloc_pages+0x74/0x350 kernel/kexec_core.c:285 kimage_alloc_normal_control_pages kernel/kexec_core.c:359 [inline] kimage_alloc_control_pages+0x153/0xa00 kernel/kexec_core.c:472 kimage_alloc_init kernel/kexec.c:67 [inline] do_kexec_load+0x439/0x860 kernel/kexec.c:130 __do_sys_kexec_load kernel/kexec.c:261 [inline] __se_sys_kexec_load kernel/kexec.c:242 [inline] __x64_sys_kexec_load+0x1bf/0x230 kernel/kexec.c:242 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 7884 tgid 7883 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2973 kimage_free_page_list+0x130/0x230 kernel/kexec_core.c:326 kimage_alloc_normal_control_pages kernel/kexec_core.c:391 [inline] kimage_alloc_control_pages+0x3d3/0xa00 kernel/kexec_core.c:472 kimage_alloc_init kernel/kexec.c:67 [inline] do_kexec_load+0x439/0x860 kernel/kexec.c:130 __do_sys_kexec_load kernel/kexec.c:261 [inline] __se_sys_kexec_load kernel/kexec.c:242 [inline] __x64_sys_kexec_load+0x1bf/0x230 kernel/kexec.c:242 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888057156280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888057156300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888057156380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888057156400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888057156480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================