================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:347 [inline] BUG: KASAN: slab-out-of-bounds in soft_cursor+0x43d/0xa50 drivers/video/fbdev/core/softcursor.c:70 Read of size 32 at addr ffff88808c54bcb0 by task syz-executor.3/1180 CPU: 1 PID: 1180 Comm: syz-executor.3 Not tainted 4.14.157-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x142/0x197 lib/dump_stack.c:58 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x123/0x190 mm/kasan/kasan.c:267 memcpy+0x24/0x50 mm/kasan/kasan.c:302 memcpy include/linux/string.h:347 [inline] soft_cursor+0x43d/0xa50 drivers/video/fbdev/core/softcursor.c:70 bit_cursor+0x11be/0x1830 drivers/video/fbdev/core/bitblit.c:386 fbcon_cursor+0x4e3/0x6f0 drivers/video/fbdev/core/fbcon.c:1347 hide_cursor+0x9d/0x2e0 drivers/tty/vt/vt.c:589 putconsxy+0x1e/0xa0 drivers/tty/vt/vt.c:4269 vcs_write+0xa29/0xbc0 drivers/tty/vt/vc_screen.c:492 __vfs_write+0x105/0x6b0 fs/read_write.c:480 vfs_write+0x198/0x500 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xfd/0x230 fs/read_write.c:582 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45a679 RSP: 002b:00007f42a60f8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a679 RDX: 0000000000000110 RSI: 0000000020001200 RDI: 0000000000000006 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f42a60f96d4 R13: 00000000004cb933 R14: 00000000004e5478 R15: 00000000ffffffff Allocated by task 11074: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc mm/kasan/kasan.c:551 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529 __do_kmalloc mm/slab.c:3720 [inline] __kmalloc+0x15d/0x7a0 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] kzalloc include/linux/slab.h:661 [inline] __register_sysctl_table+0xc7/0xe50 fs/proc/proc_sysctl.c:1304 register_net_sysctl+0x29/0x30 net/sysctl_net.c:120 __devinet_sysctl_register+0x15c/0x280 net/ipv4/devinet.c:2313 devinet_sysctl_register net/ipv4/devinet.c:2353 [inline] devinet_sysctl_register+0x120/0x1f0 net/ipv4/devinet.c:2343 inetdev_init+0x207/0x3e0 net/ipv4/devinet.c:262 inetdev_event+0xcb6/0x1010 net/ipv4/devinet.c:1461 notifier_call_chain+0x111/0x1b0 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x56/0x70 net/core/dev.c:1671 call_netdevice_notifiers net/core/dev.c:1687 [inline] register_netdevice+0x9c8/0xca0 net/core/dev.c:7697 hsr_dev_finalize+0x582/0x80a net/hsr/hsr_device.c:490 hsr_newlink+0x250/0x340 net/hsr/hsr_netlink.c:72 rtnl_newlink+0xecb/0x1700 net/core/rtnetlink.c:2719 rtnetlink_rcv_msg+0x3da/0xb70 net/core/rtnetlink.c:4306 netlink_rcv_skb+0x14f/0x3c0 net/netlink/af_netlink.c:2432 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4318 netlink_unicast_kernel net/netlink/af_netlink.c:1286 [inline] netlink_unicast+0x44d/0x650 net/netlink/af_netlink.c:1312 netlink_sendmsg+0x7c4/0xc60 net/netlink/af_netlink.c:1877 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xce/0x110 net/socket.c:656 SYSC_sendto+0x206/0x310 net/socket.c:1763 SyS_sendto+0x40/0x50 net/socket.c:1731 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Freed by task 1437: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xcc/0x270 mm/slab.c:3815 skb_free_head+0x8b/0xb0 net/core/skbuff.c:554 skb_release_data+0x543/0x7c0 net/core/skbuff.c:574 skb_release_all+0x4d/0x60 net/core/skbuff.c:631 __kfree_skb net/core/skbuff.c:645 [inline] kfree_skb+0xb5/0x350 net/core/skbuff.c:663 kauditd_hold_skb+0x11f/0x150 kernel/audit.c:543 kauditd_send_queue+0xfe/0x140 kernel/audit.c:702 kauditd_thread+0x644/0x860 kernel/audit.c:828 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 The buggy address belongs to the object at ffff88808c54b180 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 816 bytes to the right of 2048-byte region [ffff88808c54b180, ffff88808c54b980) The buggy address belongs to the page: page:ffffea0002315280 count:1 mapcount:0 mapping:ffff88808c54a080 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffff88808c54a080 0000000000000000 0000000100000003 raw: ffffea0002847d20 ffffea0002852a20 ffff8880aa800c40 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808c54bb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808c54bc00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88808c54bc80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88808c54bd00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808c54bd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================