================================================================== BUG: KASAN: slab-out-of-bounds in soft_cursor+0x458/0xa10 drivers/video/fbdev/core/softcursor.c:70 Read of size 16 at addr ffff8880562752f0 by task syz.2.1708/12307 CPU: 3 UID: 0 PID: 12307 Comm: syz.2.1708 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:186 [inline] kasan_check_range+0x10f/0x1e0 mm/kasan/generic.c:200 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105 soft_cursor+0x458/0xa10 drivers/video/fbdev/core/softcursor.c:70 ccw_cursor+0xd7f/0x15b0 drivers/video/fbdev/core/fbcon_ccw.c:341 fbcon_cursor+0x43c/0x5e0 drivers/video/fbdev/core/fbcon.c:1427 hide_cursor+0x87/0x230 drivers/tty/vt/vt.c:883 redraw_screen+0x5d4/0x760 drivers/tty/vt/vt.c:985 vc_do_resize+0xc3d/0xeb0 drivers/tty/vt/vt.c:1309 vc_resize include/linux/vt_kern.h:49 [inline] fbcon_do_set_font+0x443/0x8c0 drivers/video/fbdev/core/fbcon.c:2435 fbcon_set_font+0x4be/0x730 drivers/video/fbdev/core/fbcon.c:2518 con_font_set drivers/tty/vt/vt.c:4992 [inline] con_font_op+0x9c0/0x1040 drivers/tty/vt/vt.c:5032 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline] vt_ioctl+0xe00/0x3150 drivers/tty/vt/vt_ioctl.c:745 tty_ioctl+0x26a/0x1640 drivers/tty/tty_io.c:2792 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8c79f9e0d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8c7ada0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f8c7a226090 RCX: 00007f8c79f9e0d9 RDX: 0000200000000940 RSI: 0000000000004b72 RDI: 0000000000000007 RBP: 00007f8c7a035024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8c7a226128 R14: 00007f8c7a226090 R15: 00007fff76cf8778 Allocated by task 6911: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x2e5/0x6c0 mm/slub.c:5489 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] device_private_init drivers/base/core.c:3602 [inline] device_add+0xd3f/0x1970 drivers/base/core.c:3653 device_create_groups_vargs+0x1f8/0x270 drivers/base/core.c:4454 device_create+0xed/0x130 drivers/base/core.c:4493 vcs_make_sysfs+0x32/0x80 drivers/tty/vt/vc_screen.c:779 vc_allocate+0x539/0x880 drivers/tty/vt/vt.c:1131 con_install+0xa1/0x620 drivers/tty/vt/vt.c:3744 tty_driver_install_tty drivers/tty/tty_io.c:1295 [inline] tty_init_dev.part.0+0x9e/0x470 drivers/tty/tty_io.c:1407 tty_init_dev include/linux/err.h:78 [inline] tty_open_by_driver drivers/tty/tty_io.c:2073 [inline] tty_open+0xa63/0xfa0 drivers/tty/tty_io.c:2120 chrdev_open+0x234/0x6a0 fs/char_dev.c:411 do_dentry_open+0x6ab/0x14d0 fs/open.c:947 vfs_open+0x82/0x3f0 fs/open.c:1052 do_open fs/namei.c:4700 [inline] path_openat+0x2873/0x4280 fs/namei.c:4863 do_file_open+0x20e/0x430 fs/namei.c:4892 do_sys_openat2+0x10f/0x1e0 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888056275000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 480 bytes to the right of allocated 272-byte region [ffff888056275000, ffff888056275110) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56274 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801bc42c80 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801bc42c80 dead000000000100 dead000000000122 head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5726, tgid 5726 (syz-executor), ts 47841551915, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab mm/slub.c:3380 [inline] new_slab+0xa2/0x640 mm/slub.c:3426 refill_objects+0xe3/0x410 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] __kmalloc_cache_noprof+0x479/0x6c0 mm/slub.c:5485 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] inetdev_init+0x66/0x570 net/ipv4/devinet.c:273 inetdev_event+0x7fa/0x17f0 net/ipv4/devinet.c:1590 notifier_call_chain+0x99/0x3f0 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2250 call_netdevice_notifiers_extack net/core/dev.c:2288 [inline] call_netdevice_notifiers net/core/dev.c:2302 [inline] register_netdevice+0x1998/0x25a0 net/core/dev.c:11484 macvlan_common_newlink+0xf70/0x18b0 drivers/net/macvlan.c:1554 rtnl_newlink_create net/core/rtnetlink.c:3913 [inline] __rtnl_newlink net/core/rtnetlink.c:4044 [inline] rtnl_newlink+0x1499/0x2380 net/core/rtnetlink.c:4159 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:7076 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2556 page_owner free stack trace missing Memory state around the buggy address: ffff888056275180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888056275200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888056275280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888056275300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888056275380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================