================================================================== 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:623 Read of size 2 at addr ffff88803037f5f2 by task syz.3.1292/11882 CPU: 0 UID: 0 PID: 11882 Comm: syz.3.1292 Tainted: G U syzkaller #0 PREEMPT(full) Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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: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:623 fbcon_init+0xd77/0x1900 drivers/video/fbdev/core/fbcon.c:1156 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+0xa24/0x12e0 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/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe8f5b8efc9 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:00007fe8f6ae0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fe8f5de5fa0 RCX: 00007fe8f5b8efc9 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000004 RBP: 00007fe8f5c11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe8f5de6038 R14: 00007fe8f5de5fa0 R15: 00007ffda2250518 Allocated by task 11561: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5642 [inline] __kmalloc_node_track_caller_noprof+0x345/0x8a0 mm/slub.c:5751 kmemdup_noprof+0x29/0x60 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:765 [inline] shmem_symlink+0x257/0x9f0 mm/shmem.c:4110 vfs_symlink fs/namei.c:4817 [inline] vfs_symlink+0x403/0x680 fs/namei.c:4801 do_symlinkat+0x261/0x310 fs/namei.c:4843 __do_sys_symlinkat fs/namei.c:4859 [inline] __se_sys_symlinkat fs/namei.c:4856 [inline] __x64_sys_symlinkat+0x93/0xc0 fs/namei.c:4856 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 11569: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2539 [inline] slab_free mm/slub.c:6630 [inline] kfree+0x2b8/0x6d0 mm/slub.c:6837 shmem_free_in_core_inode+0x8f/0xb0 mm/shmem.c:5156 i_callback+0x46/0x70 fs/inode.c:325 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0x79c/0x1530 kernel/rcu/tree.c:2861 handle_softirqs+0x219/0x8e0 kernel/softirq.c:622 do_softirq kernel/softirq.c:523 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:510 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:450 nl80211_netlink_notify net/wireless/nl80211.c:21508 [inline] nl80211_netlink_notify+0x2fd/0x970 net/wireless/nl80211.c:21471 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85 blocking_notifier_call_chain kernel/notifier.c:380 [inline] blocking_notifier_call_chain+0x69/0xa0 kernel/notifier.c:368 netlink_release+0x16cf/0x2080 net/netlink/af_netlink.c:763 __sock_release+0xb3/0x270 net/socket.c:662 sock_close+0x1c/0x30 net/socket.c:1455 __fput+0x402/0xb70 fs/file_table.c:468 fput_close_sync+0x118/0x210 fs/file_table.c:573 __do_sys_close fs/open.c:1589 [inline] __se_sys_close fs/open.c:1574 [inline] __x64_sys_close+0x8b/0x120 fs/open.c:1574 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88803037f5e0 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 [ffff88803037f5e0, ffff88803037f5f0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3037f flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88813ffa6640 ffffea0001748600 dead000000000002 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 5832, tgid 5832 (syz-executor), ts 312711271835, free_ts 312711165578 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5183 alloc_slab_page mm/slub.c:3057 [inline] allocate_slab mm/slub.c:3228 [inline] new_slab+0xa5/0x360 mm/slub.c:3282 ___slab_alloc+0xdae/0x1a60 mm/slub.c:4651 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4770 __slab_alloc_node mm/slub.c:4846 [inline] slab_alloc_node mm/slub.c:5268 [inline] __do_kmalloc_node mm/slub.c:5641 [inline] __kvmalloc_node_noprof+0x5aa/0x9c0 mm/slub.c:7100 xt_jumpstack_alloc net/netfilter/x_tables.c:1356 [inline] xt_replace_table+0x1ed/0x950 net/netfilter/x_tables.c:1395 __do_replace+0x1cf/0x9f0 net/ipv4/netfilter/arp_tables.c:912 do_replace net/ipv6/netfilter/ip6_tables.c:1158 [inline] do_ip6t_set_ctl+0x806/0xa70 net/ipv6/netfilter/ip6_tables.c:1644 nf_setsockopt+0x8d/0xf0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x135/0x170 net/ipv6/ipv6_sockglue.c:978 tcp_setsockopt+0xa7/0x100 net/ipv4/tcp.c:4142 do_sock_setsockopt+0xf3/0x1d0 net/socket.c:2360 __sys_setsockopt+0x120/0x1a0 net/socket.c:2385 __do_sys_setsockopt net/socket.c:2391 [inline] __se_sys_setsockopt net/socket.c:2388 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2388 page last free pid 5832 tgid 5832 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2906 ___free_pages_bulk mm/kasan/shadow.c:333 [inline] __kasan_populate_vmalloc mm/kasan/shadow.c:393 [inline] kasan_populate_vmalloc+0x1eb/0x2d0 mm/kasan/shadow.c:435 alloc_vmap_area+0x960/0x29e0 mm/vmalloc.c:2098 __get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3193 __vmalloc_node_range_noprof+0x271/0x1480 mm/vmalloc.c:3857 __vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:3960 xt_counters_alloc+0x4c/0x70 net/netfilter/x_tables.c:1381 __do_replace+0x97/0x9f0 net/ipv4/netfilter/arp_tables.c:894 do_replace net/ipv6/netfilter/ip6_tables.c:1158 [inline] do_ip6t_set_ctl+0x806/0xa70 net/ipv6/netfilter/ip6_tables.c:1644 nf_setsockopt+0x8d/0xf0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x135/0x170 net/ipv6/ipv6_sockglue.c:978 tcp_setsockopt+0xa7/0x100 net/ipv4/tcp.c:4142 do_sock_setsockopt+0xf3/0x1d0 net/socket.c:2360 __sys_setsockopt+0x120/0x1a0 net/socket.c:2385 __do_sys_setsockopt net/socket.c:2391 [inline] __se_sys_setsockopt net/socket.c:2388 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2388 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 Memory state around the buggy address: ffff88803037f480: fa fb fc fc fa fb fc fc 00 00 fc fc fa fb fc fc ffff88803037f500: fa fb fc fc 00 00 fc fc fa fb fc fc 00 01 fc fc >ffff88803037f580: 00 00 fc fc fa fb fc fc 00 00 fc fc fa fb fc fc ^ ffff88803037f600: 00 04 fc fc fa fb fc fc fa fb fc fc 00 04 fc fc ffff88803037f680: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc ==================================================================