================================================================== 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+0xa03/0xc70 drivers/video/fbdev/core/fbcon.c:613 Read of size 2 at addr ffff888035ad63d2 by task syz.5.2574/18881 CPU: 1 UID: 0 PID: 18881 Comm: syz.5.2574 Tainted: G U 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 PREEMPT(full) Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 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:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189 __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:613 fbcon_init+0xd77/0x1900 drivers/video/fbdev/core/fbcon.c:1145 visual_init+0x31d/0x620 drivers/tty/vt/vt.c:1011 do_bind_con_driver.isra.0+0x57a/0xbf0 drivers/tty/vt/vt.c:3831 vt_bind drivers/tty/vt/vt.c:3987 [inline] store_bind+0x61d/0x760 drivers/tty/vt/vt.c:4059 dev_attr_store+0x55/0x80 drivers/base/core.c:2440 sysfs_kf_write+0xef/0x150 fs/sysfs/file.c:145 kernfs_fop_write_iter+0x351/0x510 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x5ba/0x1180 fs/read_write.c:684 ksys_write+0x12a/0x240 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ffa6018e969 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:00007ffa60ff3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ffa603b5fa0 RCX: 00007ffa6018e969 RDX: 00000000fffffdef RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007ffa60210ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffa603b5fa0 R15: 00007ffcaa52c2f8 Allocated by task 18890: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4341 [inline] __kmalloc_noprof+0x223/0x510 mm/slub.c:4353 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] lsm_blob_alloc+0x68/0x90 security/security.c:684 lsm_sock_alloc security/security.c:4839 [inline] security_sk_alloc+0x30/0x270 security/security.c:4855 sk_prot_alloc+0x1c7/0x2a0 net/core/sock.c:2201 sk_alloc+0x36/0xc20 net/core/sock.c:2254 __netlink_create+0x5e/0x2c0 net/netlink/af_netlink.c:629 netlink_create+0x39e/0x620 net/netlink/af_netlink.c:687 __sock_create+0x335/0x8d0 net/socket.c:1541 sock_create net/socket.c:1599 [inline] __sys_socket_create net/socket.c:1636 [inline] __sys_socket+0x14d/0x260 net/socket.c:1683 __do_sys_socket net/socket.c:1697 [inline] __se_sys_socket net/socket.c:1695 [inline] __x64_sys_socket+0x72/0xb0 net/socket.c:1695 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888035ad63c0 which belongs to the cache kmalloc-16 of size 16 The buggy address is located 2 bytes to the right of allocated 16-byte region [ffff888035ad63c0, ffff888035ad63d0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x35ad6 anon flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801b441640 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080800080 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 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 5828, tgid 5828 (syz-executor), ts 577450026710, free_ts 574654459817 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1718 prep_new_page mm/page_alloc.c:1726 [inline] get_page_from_freelist+0x135c/0x3920 mm/page_alloc.c:3688 __alloc_frozen_pages_noprof+0x263/0x23a0 mm/page_alloc.c:4970 alloc_slab_page mm/slub.c:2470 [inline] allocate_slab mm/slub.c:2632 [inline] new_slab+0x94/0x340 mm/slub.c:2686 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3872 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3962 __slab_alloc_node mm/slub.c:4037 [inline] slab_alloc_node mm/slub.c:4198 [inline] __do_kmalloc_node mm/slub.c:4340 [inline] __kvmalloc_node_noprof+0x3a6/0x600 mm/slub.c:5026 xt_jumpstack_alloc net/netfilter/x_tables.c:1355 [inline] xt_replace_table+0x1e3/0x950 net/netfilter/x_tables.c:1394 __do_replace+0x1cf/0x9e0 net/ipv4/netfilter/ip_tables.c:1064 do_replace net/ipv4/netfilter/ip_tables.c:1141 [inline] do_ipt_set_ctl+0x7f7/0xa60 net/ipv4/netfilter/ip_tables.c:1635 nf_setsockopt+0x8a/0xf0 net/netfilter/nf_sockopt.c:101 ip_setsockopt+0xcb/0xf0 net/ipv4/ip_sockglue.c:1424 tcp_setsockopt+0xa4/0x100 net/ipv4/tcp.c:4077 do_sock_setsockopt+0x221/0x470 net/socket.c:2296 __sys_setsockopt+0x120/0x1a0 net/socket.c:2321 __do_sys_setsockopt net/socket.c:2327 [inline] __se_sys_setsockopt net/socket.c:2324 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2324 page last free pid 14109 tgid 14108 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0x69d/0xff0 mm/page_alloc.c:2725 kimage_free_page_list+0x130/0x230 kernel/kexec_core.c:324 kimage_alloc_normal_control_pages kernel/kexec_core.c:389 [inline] kimage_alloc_control_pages+0x3b3/0x910 kernel/kexec_core.c:470 kimage_alloc_init kernel/kexec.c:67 [inline] do_kexec_load+0x480/0x8d0 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/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888035ad6280: 00 00 fc fc 00 00 fc fc fa fb fc fc 00 00 fc fc ffff888035ad6300: 00 00 fc fc 00 00 fc fc 00 06 fc fc 00 00 fc fc >ffff888035ad6380: 00 06 fc fc fa fb fc fc 00 00 fc fc 00 00 fc fc ^ ffff888035ad6400: fa fb fc fc 00 00 fc fc 00 06 fc fc fa fb fc fc ffff888035ad6480: 00 00 fc fc 00 00 fc fc 00 00 fc fc 00 00 fc fc ==================================================================