================================================================== 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:630 Read of size 2 at addr ffff8880299816c8 by task syz.7.2194/16692 CPU: 1 UID: 0 PID: 16692 Comm: syz.7.2194 Tainted: GF R U syzkaller #0 PREEMPT(full) Tainted: [F]=FORCED_MODULE, [R]=FORCED_RMMOD, [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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:183 [inline] kasan_check_range+0x100/0x1b0 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:630 fbcon_init+0xd77/0x1900 drivers/video/fbdev/core/fbcon.c:1163 visual_init+0x320/0x620 drivers/tty/vt/vt.c:1019 do_bind_con_driver.isra.0+0x57a/0xbf0 drivers/tty/vt/vt.c:3915 vt_bind drivers/tty/vt/vt.c:4071 [inline] store_bind+0x61d/0x760 drivers/tty/vt/vt.c:4143 dev_attr_store+0x58/0x80 drivers/base/core.c:2437 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145 kernfs_fop_write_iter+0x354/0x510 fs/kernfs/file.c:334 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/0x490 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f227ad8ebe9 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:00007f227834b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f227afb6450 RCX: 00007f227ad8ebe9 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000007 RBP: 00007f227ae11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f227afb64e8 R14: 00007f227afb6450 R15: 00007ffc1f904a28 Allocated by task 5858: 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:388 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4365 [inline] __kmalloc_node_track_caller_noprof+0x221/0x510 mm/slub.c:4384 __kmemdup_nul mm/util.c:64 [inline] kstrdup+0x53/0x100 mm/util.c:84 kstrdup_const+0x63/0x80 mm/util.c:104 __kernfs_new_node+0x9b/0x8e0 fs/kernfs/dir.c:633 kernfs_new_node+0x13c/0x1e0 fs/kernfs/dir.c:713 kernfs_create_dir_ns+0x4c/0x1a0 fs/kernfs/dir.c:1083 sysfs_create_dir_ns+0x13a/0x2b0 fs/sysfs/dir.c:59 create_dir lib/kobject.c:73 [inline] kobject_add_internal+0x2c4/0x9b0 lib/kobject.c:240 kobject_add_varg lib/kobject.c:374 [inline] kobject_init_and_add+0x11b/0x190 lib/kobject.c:457 netdev_queue_add_kobject net/core/net-sysfs.c:1995 [inline] netdev_queue_update_kobjects+0x32d/0x720 net/core/net-sysfs.c:2054 register_queue_kobjects net/core/net-sysfs.c:2117 [inline] netdev_register_kobject+0x2b3/0x3d0 net/core/net-sysfs.c:2360 register_netdevice+0x13dc/0x2270 net/core/dev.c:11194 veth_newlink+0x30f/0xa00 drivers/net/veth.c:1855 rtnl_newlink_create net/core/rtnetlink.c:3825 [inline] __rtnl_newlink net/core/rtnetlink.c:3942 [inline] rtnl_newlink+0xc45/0x2000 net/core/rtnetlink.c:4057 rtnetlink_rcv_msg+0x95b/0xe90 net/core/rtnetlink.c:6946 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] __sys_sendto+0x4a3/0x520 net/socket.c:2228 __do_sys_sendto net/socket.c:2235 [inline] __se_sys_sendto net/socket.c:2231 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2231 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880299816c0 which belongs to the cache kmalloc-8 of size 8 The buggy address is located 3 bytes to the right of allocated 5-byte region [ffff8880299816c0, ffff8880299816c5) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x29981 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801b841500 dead000000000100 dead000000000122 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 0x52c00(GFP_NOIO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 17819574970, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab mm/slub.c:2655 [inline] new_slab+0x247/0x330 mm/slub.c:2709 ___slab_alloc+0xcf2/0x1740 mm/slub.c:3891 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981 __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] __kmalloc_cache_noprof+0xfb/0x3e0 mm/slub.c:4391 kmalloc_noprof include/linux/slab.h:905 [inline] usb_control_msg+0xbc/0x4a0 drivers/usb/core/message.c:144 usb_get_descriptor+0xbb/0x1b0 drivers/usb/core/message.c:794 usb_get_configuration+0x291/0x6530 drivers/usb/core/config.c:952 usb_enumerate_device drivers/usb/core/hub.c:2526 [inline] usb_new_device+0x11d3/0x1a60 drivers/usb/core/hub.c:2664 register_root_hub+0x299/0x730 drivers/usb/core/hcd.c:994 usb_add_hcd+0xaf2/0x1730 drivers/usb/core/hcd.c:2989 dummy_hcd_probe+0x15c/0x380 drivers/usb/gadget/udc/dummy_hcd.c:2694 platform_probe+0x106/0x1d0 drivers/base/platform.c:1405 page_owner free stack trace missing Memory state around the buggy address: ffff888029981580: 04 fc fc fc 04 fc fc fc 00 fc fc fc 06 fc fc fc ffff888029981600: 06 fc fc fc 00 fc fc fc 00 fc fc fc 06 fc fc fc >ffff888029981680: 06 fc fc fc 06 fc fc fc 05 fc fc fc 05 fc fc fc ^ ffff888029981700: 00 fc fc fc 02 fc fc fc 05 fc fc fc 05 fc fc fc ffff888029981780: 00 fc fc fc 05 fc fc fc 00 fc fc fc fa fc fc fc ==================================================================