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:00007fa3f8600038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa3f79b6080 RCX: 00007fa3f778e969 RDX: 00000000fffffdef RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007fa3f7810ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa3f79b6080 R15: 00007ffc178d3638 ================================================================== 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 6 at addr ffff888033ba9876 by task syz.3.441/8512 CPU: 1 UID: 0 PID: 8512 Comm: syz.3.441 Tainted: G U 6.15.0-rc7-syzkaller #0 PREEMPT(full) Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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+0x58/0x80 drivers/base/core.c:2440 sysfs_kf_write+0xf2/0x150 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: 0033:0x7fa3f778e969 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:00007fa3f8600038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa3f79b6080 RCX: 00007fa3f778e969 RDX: 00000000fffffdef RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007fa3f7810ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa3f79b6080 R15: 00007ffc178d3638 Allocated by task 8511: 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:4327 [inline] __kmalloc_noprof+0x223/0x510 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] kobject_get_path+0xd2/0x2a0 lib/kobject.c:161 kobject_uevent_env+0x289/0x1870 lib/kobject_uevent.c:545 rx_queue_add_kobject net/core/net-sysfs.c:1259 [inline] net_rx_queue_update_kobjects+0x1de/0x770 net/core/net-sysfs.c:1301 register_queue_kobjects net/core/net-sysfs.c:2093 [inline] netdev_register_kobject+0x269/0x3a0 net/core/net-sysfs.c:2340 register_netdevice+0x13dc/0x2270 net/core/dev.c:10999 __ip_tunnel_create+0x4a8/0x680 net/ipv4/ip_tunnel.c:268 ip_tunnel_init_net+0x22f/0x7d0 net/ipv4/ip_tunnel.c:1161 ops_init+0x1e2/0x5f0 net/core/net_namespace.c:138 setup_net+0x21e/0x850 net/core/net_namespace.c:364 copy_net_ns+0x2a6/0x5f0 net/core/net_namespace.c:518 create_new_namespaces+0x3ea/0xad0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x45b/0xa40 kernel/fork.c:3376 __do_sys_unshare kernel/fork.c:3447 [inline] __se_sys_unshare kernel/fork.c:3445 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3445 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 Freed by task 8511: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2380 [inline] slab_free mm/slub.c:4642 [inline] kfree+0x2b6/0x4d0 mm/slub.c:4841 kobject_uevent_env+0x2db/0x1870 lib/kobject_uevent.c:639 rx_queue_add_kobject net/core/net-sysfs.c:1259 [inline] net_rx_queue_update_kobjects+0x1de/0x770 net/core/net-sysfs.c:1301 register_queue_kobjects net/core/net-sysfs.c:2093 [inline] netdev_register_kobject+0x269/0x3a0 net/core/net-sysfs.c:2340 register_netdevice+0x13dc/0x2270 net/core/dev.c:10999 __ip_tunnel_create+0x4a8/0x680 net/ipv4/ip_tunnel.c:268 ip_tunnel_init_net+0x22f/0x7d0 net/ipv4/ip_tunnel.c:1161 ops_init+0x1e2/0x5f0 net/core/net_namespace.c:138 setup_net+0x21e/0x850 net/core/net_namespace.c:364 copy_net_ns+0x2a6/0x5f0 net/core/net_namespace.c:518 create_new_namespaces+0x3ea/0xad0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x45b/0xa40 kernel/fork.c:3376 __do_sys_unshare kernel/fork.c:3447 [inline] __se_sys_unshare kernel/fork.c:3445 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3445 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 ffff888033ba9800 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 54 bytes to the right of allocated 64-byte region [ffff888033ba9800, ffff888033ba9840) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x33ba9 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801b4418c0 ffffea0000cd0100 dead000000000004 raw: 0000000000000000 0000000000200020 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 6657, tgid 6656 (syz.2.124), ts 165519983737, free_ts 165197205662 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1714 prep_new_page mm/page_alloc.c:1722 [inline] get_page_from_freelist+0x135c/0x3920 mm/page_alloc.c:3684 __alloc_frozen_pages_noprof+0x263/0x23a0 mm/page_alloc.c:4966 alloc_slab_page mm/slub.c:2452 [inline] allocate_slab mm/slub.c:2618 [inline] new_slab+0x94/0x340 mm/slub.c:2672 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3858 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3948 __slab_alloc_node mm/slub.c:4023 [inline] slab_alloc_node mm/slub.c:4184 [inline] __do_kmalloc_node mm/slub.c:4326 [inline] __kmalloc_node_noprof+0x2ed/0x500 mm/slub.c:4333 kmalloc_array_node_noprof include/linux/slab.h:1020 [inline] alloc_slab_obj_exts+0x41/0xa0 mm/slub.c:1992 account_slab mm/slub.c:2577 [inline] allocate_slab mm/slub.c:2637 [inline] new_slab+0x28c/0x340 mm/slub.c:2672 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3858 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3948 __slab_alloc_node mm/slub.c:4023 [inline] slab_alloc_node mm/slub.c:4184 [inline] __do_kmalloc_node mm/slub.c:4326 [inline] __kmalloc_node_track_caller_noprof+0x2ee/0x510 mm/slub.c:4346 kmemdup_noprof+0x29/0x60 mm/util.c:137 kmemdup_noprof include/linux/fortify-string.h:765 [inline] neigh_sysctl_register+0xb2/0x670 net/core/neighbour.c:3732 addrconf_sysctl_register+0xb9/0x1f0 net/ipv6/addrconf.c:7292 ipv6_add_dev+0xb39/0x15f0 net/ipv6/addrconf.c:458 page last free pid 6665 tgid 6664 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1258 [inline] __free_frozen_pages+0x69d/0xff0 mm/page_alloc.c:2721 discard_slab mm/slub.c:2716 [inline] __put_partials+0x16d/0x1c0 mm/slub.c:3185 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4203 ptlock_alloc+0x1f/0x70 mm/memory.c:7354 ptlock_init include/linux/mm.h:3074 [inline] pagetable_pte_ctor include/linux/mm.h:3122 [inline] __pte_alloc_one_noprof include/asm-generic/pgalloc.h:73 [inline] pte_alloc_one+0x6d/0x380 arch/x86/mm/pgtable.c:17 __pte_alloc+0x6d/0x3c0 mm/memory.c:430 do_anonymous_page mm/memory.c:4968 [inline] do_pte_missing+0x2925/0x3fb0 mm/memory.c:4158 handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309 faultin_page mm/gup.c:1193 [inline] __get_user_pages+0x771/0x36f0 mm/gup.c:1491 populate_vma_page_range+0x278/0x3a0 mm/gup.c:1929 __mm_populate+0x1d8/0x380 mm/gup.c:2032 mm_populate include/linux/mm.h:3487 [inline] vm_mmap_pgoff+0x362/0x450 mm/util.c:584 Memory state around the buggy address: ffff888033ba9700: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff888033ba9780: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc >ffff888033ba9800: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff888033ba9880: 00 00 00 00 04 fc fc fc fc fc fc fc fc fc fc fc ffff888033ba9900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: ff c3 inc %ebx 2: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 9: 00 00 00 c: 0f 1f 40 00 nopl 0x0(%rax) 10: 48 89 f8 mov %rdi,%rax 13: 48 89 f7 mov %rsi,%rdi 16: 48 89 d6 mov %rdx,%rsi 19: 48 89 ca mov %rcx,%rdx 1c: 4d 89 c2 mov %r8,%r10 1f: 4d 89 c8 mov %r9,%r8 22: 4c 8b 4c 24 08 mov 0x8(%rsp),%r9 27: 0f 05 syscall * 29: 48 3d 01 f0 ff ff cmp $0xfffffffffffff001,%rax <-- trapping instruction 2f: 73 01 jae 0x32 31: c3 ret 32: 48 c7 c1 a8 ff ff ff mov $0xffffffffffffffa8,%rcx 39: f7 d8 neg %eax 3b: 64 89 01 mov %eax,%fs:(%rcx) 3e: 48 rex.W