Warning: Permanently added '10.128.0.28' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 152.993752] ================================================================== [ 153.001185] BUG: KASAN: use-after-free in refcount_dec_not_one+0x71/0x1d0 [ 153.008097] Read of size 4 at addr ffff8880a51b9898 by task syz-executor392/8909 [ 153.015619] [ 153.017233] CPU: 0 PID: 8909 Comm: syz-executor392 Not tainted 4.19.211-syzkaller #0 [ 153.025103] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 153.034436] Call Trace: [ 153.037009] dump_stack+0x1fc/0x2ef [ 153.040621] print_address_description.cold+0x54/0x219 [ 153.045892] kasan_report_error.cold+0x8a/0x1b9 [ 153.050546] ? refcount_dec_not_one+0x71/0x1d0 [ 153.055123] kasan_report+0x8f/0xa0 [ 153.058733] ? refcount_dec_not_one+0x71/0x1d0 [ 153.063296] refcount_dec_not_one+0x71/0x1d0 [ 153.067691] ? refcount_dec_and_test_checked+0x20/0x20 [ 153.072951] ? nbd_config_put+0x5da/0x870 [ 153.077082] refcount_dec_and_mutex_lock+0x1c/0x80 [ 153.081993] nbd_genl_connect+0x11ee/0x1630 [ 153.086299] ? nbd_xmit_timeout+0x730/0x730 [ 153.090602] ? __sanitizer_cov_trace_switch+0x4b/0x80 [ 153.095773] ? validate_nla+0x270/0x820 [ 153.099729] ? nla_parse+0x1b2/0x290 [ 153.103442] genl_family_rcv_msg+0x642/0xc40 [ 153.107847] ? genl_rcv+0x40/0x40 [ 153.111285] ? genl_rcv_msg+0x12f/0x160 [ 153.115242] ? mutex_trylock+0x1a0/0x1a0 [ 153.119290] ? __radix_tree_lookup+0x216/0x370 [ 153.123860] genl_rcv_msg+0xbf/0x160 [ 153.127568] netlink_rcv_skb+0x160/0x440 [ 153.131609] ? genl_family_rcv_msg+0xc40/0xc40 [ 153.136186] ? netlink_ack+0xae0/0xae0 [ 153.140057] ? genl_rcv+0x15/0x40 [ 153.143493] genl_rcv+0x24/0x40 [ 153.146749] netlink_unicast+0x4d5/0x690 [ 153.150793] ? netlink_sendskb+0x110/0x110 [ 153.155008] ? _copy_from_iter_full+0x229/0x7c0 [ 153.159670] ? __phys_addr_symbol+0x2c/0x70 [ 153.163986] ? __check_object_size+0x17b/0x3e0 [ 153.168550] netlink_sendmsg+0x6c3/0xc50 [ 153.172593] ? aa_af_perm+0x230/0x230 [ 153.176372] ? nlmsg_notify+0x1f0/0x1f0 [ 153.180328] ? kernel_recvmsg+0x220/0x220 [ 153.184553] ? nlmsg_notify+0x1f0/0x1f0 [ 153.188532] sock_sendmsg+0xc3/0x120 [ 153.192225] ___sys_sendmsg+0x7bb/0x8e0 [ 153.196181] ? copy_msghdr_from_user+0x440/0x440 [ 153.200918] ? netlink_dump+0xc10/0xc10 [ 153.204875] ? nlmsg_notify+0x1f0/0x1f0 [ 153.208834] ? security_socket_recvmsg+0x8f/0xc0 [ 153.213593] ? __sys_recvfrom+0x2cd/0x3a0 [ 153.217723] ? __ia32_sys_send+0x100/0x100 [ 153.221941] ? __fdget+0x1a0/0x230 [ 153.225462] __x64_sys_sendmsg+0x132/0x220 [ 153.229673] ? __sys_sendmsg+0x1b0/0x1b0 [ 153.233720] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 153.239066] ? trace_hardirqs_off_caller+0x6e/0x210 [ 153.244061] ? do_syscall_64+0x21/0x620 [ 153.248015] do_syscall_64+0xf9/0x620 [ 153.251796] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 153.256966] RIP: 0033:0x7f77d00bfb69 [ 153.260672] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48 [ 153.279567] RSP: 002b:00007ffd92dc0058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 153.287307] RAX: ffffffffffffffda RBX: 00007ffd92dc00a0 RCX: 00007f77d00bfb69 [ 153.294557] RDX: 0000000000000000 RSI: 0000000020000380 RDI: 0000000000000003 [ 153.301818] RBP: 0000000000000000 R08: 0000000000000000 R09: 00007f77d0133ec0 [ 153.309088] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd92dc0090 [ 153.316344] R13: 000000000002557a R14: 00007ffd92dc008c R15: 431bde82d7b634db [ 153.323604] [ 153.325214] Allocated by task 8904: [ 153.328840] kmem_cache_alloc_trace+0x12f/0x380 [ 153.333500] nbd_dev_add+0x44/0x890 [ 153.337109] nbd_genl_connect+0x4cc/0x1630 [ 153.341358] genl_family_rcv_msg+0x642/0xc40 [ 153.345826] genl_rcv_msg+0xbf/0x160 [ 153.349520] netlink_rcv_skb+0x160/0x440 [ 153.353562] genl_rcv+0x24/0x40 [ 153.356848] netlink_unicast+0x4d5/0x690 [ 153.360996] netlink_sendmsg+0x6c3/0xc50 [ 153.365138] sock_sendmsg+0xc3/0x120 [ 153.368843] ___sys_sendmsg+0x7bb/0x8e0 [ 153.372801] __x64_sys_sendmsg+0x132/0x220 [ 153.377043] do_syscall_64+0xf9/0x620 [ 153.380831] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 153.385995] [ 153.387604] Freed by task 8909: [ 153.390867] kfree+0xcc/0x210 [ 153.393952] nbd_put.part.0+0xfe/0x140 [ 153.397825] nbd_config_put+0x6a0/0x870 [ 153.401785] nbd_genl_connect+0x11bb/0x1630 [ 153.406100] genl_family_rcv_msg+0x642/0xc40 [ 153.410486] genl_rcv_msg+0xbf/0x160 [ 153.414178] netlink_rcv_skb+0x160/0x440 [ 153.418216] genl_rcv+0x24/0x40 [ 153.421489] netlink_unicast+0x4d5/0x690 [ 153.425530] netlink_sendmsg+0x6c3/0xc50 [ 153.429583] sock_sendmsg+0xc3/0x120 [ 153.433273] ___sys_sendmsg+0x7bb/0x8e0 [ 153.437225] __x64_sys_sendmsg+0x132/0x220 [ 153.441441] do_syscall_64+0xf9/0x620 [ 153.445221] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 153.450387] [ 153.452006] The buggy address belongs to the object at ffff8880a51b97c0 [ 153.452006] which belongs to the cache kmalloc-512 of size 512 [ 153.464642] The buggy address is located 216 bytes inside of [ 153.464642] 512-byte region [ffff8880a51b97c0, ffff8880a51b99c0) [ 153.476498] The buggy address belongs to the page: [ 153.481417] page:ffffea0002946e40 count:1 mapcount:0 mapping:ffff88813bff0940 index:0xffff8880a51b9540 [ 153.490843] flags: 0xfff00000000100(slab) [ 153.494976] raw: 00fff00000000100 ffffea0002aeff08 ffffea0002a36ec8 ffff88813bff0940 [ 153.502842] raw: ffff8880a51b9540 ffff8880a51b9040 0000000100000003 0000000000000000 [ 153.510727] page dumped because: kasan: bad access detected [ 153.516416] [ 153.518020] Memory state around the buggy address: [ 153.522930] ffff8880a51b9780: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 153.530269] ffff8880a51b9800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 153.537606] >ffff8880a51b9880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 153.544942] ^ [ 153.549073] ffff8880a51b9900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 153.556412] ffff8880a51b9980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 153.563746] ================================================================== [ 153.571093] Disabling lock debugging due to kernel taint [ 153.585065] Kernel panic - not syncing: panic_on_warn set ... [ 153.585065] [ 153.592450] CPU: 1 PID: 8909 Comm: syz-executor392 Tainted: G B 4.19.211-syzkaller #0 [ 153.601715] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 153.611061] Call Trace: [ 153.613632] dump_stack+0x1fc/0x2ef [ 153.617244] panic+0x26a/0x50e [ 153.620421] ? __warn_printk+0xf3/0xf3 [ 153.624288] ? preempt_schedule_common+0x45/0xc0 [ 153.629039] ? ___preempt_schedule+0x16/0x18 [ 153.633425] ? trace_hardirqs_on+0x55/0x210 [ 153.637726] kasan_end_report+0x43/0x49 [ 153.641681] kasan_report_error.cold+0xa7/0x1b9 [ 153.646332] ? refcount_dec_not_one+0x71/0x1d0 [ 153.650890] kasan_report+0x8f/0xa0 [ 153.654507] ? refcount_dec_not_one+0x71/0x1d0 [ 153.659070] refcount_dec_not_one+0x71/0x1d0 [ 153.663456] ? refcount_dec_and_test_checked+0x20/0x20 [ 153.668712] ? nbd_config_put+0x5da/0x870 [ 153.672839] refcount_dec_and_mutex_lock+0x1c/0x80 [ 153.677748] nbd_genl_connect+0x11ee/0x1630 [ 153.682049] ? nbd_xmit_timeout+0x730/0x730 [ 153.686351] ? __sanitizer_cov_trace_switch+0x4b/0x80 [ 153.691520] ? validate_nla+0x270/0x820 [ 153.695474] ? nla_parse+0x1b2/0x290 [ 153.699168] genl_family_rcv_msg+0x642/0xc40 [ 153.703556] ? genl_rcv+0x40/0x40 [ 153.706990] ? genl_rcv_msg+0x12f/0x160 [ 153.710941] ? mutex_trylock+0x1a0/0x1a0 [ 153.714980] ? __radix_tree_lookup+0x216/0x370 [ 153.719543] genl_rcv_msg+0xbf/0x160 [ 153.723238] netlink_rcv_skb+0x160/0x440 [ 153.727276] ? genl_family_rcv_msg+0xc40/0xc40 [ 153.731836] ? netlink_ack+0xae0/0xae0 [ 153.735702] ? genl_rcv+0x15/0x40 [ 153.739135] genl_rcv+0x24/0x40 [ 153.742395] netlink_unicast+0x4d5/0x690 [ 153.746458] ? netlink_sendskb+0x110/0x110 [ 153.750671] ? _copy_from_iter_full+0x229/0x7c0 [ 153.755319] ? __phys_addr_symbol+0x2c/0x70 [ 153.759620] ? __check_object_size+0x17b/0x3e0 [ 153.764180] netlink_sendmsg+0x6c3/0xc50 [ 153.768222] ? aa_af_perm+0x230/0x230 [ 153.772007] ? nlmsg_notify+0x1f0/0x1f0 [ 153.775956] ? kernel_recvmsg+0x220/0x220 [ 153.780082] ? nlmsg_notify+0x1f0/0x1f0 [ 153.784032] sock_sendmsg+0xc3/0x120 [ 153.787727] ___sys_sendmsg+0x7bb/0x8e0 [ 153.791677] ? copy_msghdr_from_user+0x440/0x440 [ 153.796406] ? netlink_dump+0xc10/0xc10 [ 153.800370] ? nlmsg_notify+0x1f0/0x1f0 [ 153.804322] ? security_socket_recvmsg+0x8f/0xc0 [ 153.809051] ? __sys_recvfrom+0x2cd/0x3a0 [ 153.813174] ? __ia32_sys_send+0x100/0x100 [ 153.817386] ? __fdget+0x1a0/0x230 [ 153.820904] __x64_sys_sendmsg+0x132/0x220 [ 153.825130] ? __sys_sendmsg+0x1b0/0x1b0 [ 153.829174] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 153.834514] ? trace_hardirqs_off_caller+0x6e/0x210 [ 153.839512] ? do_syscall_64+0x21/0x620 [ 153.843463] do_syscall_64+0xf9/0x620 [ 153.847255] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 153.852419] RIP: 0033:0x7f77d00bfb69 [ 153.856137] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48 [ 153.875017] RSP: 002b:00007ffd92dc0058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 153.882704] RAX: ffffffffffffffda RBX: 00007ffd92dc00a0 RCX: 00007f77d00bfb69 [ 153.889952] RDX: 0000000000000000 RSI: 0000000020000380 RDI: 0000000000000003 [ 153.897291] RBP: 0000000000000000 R08: 0000000000000000 R09: 00007f77d0133ec0 [ 153.904535] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd92dc0090 [ 153.911780] R13: 000000000002557a R14: 00007ffd92dc008c R15: 431bde82d7b634db [ 153.919196] Kernel Offset: disabled [ 153.922807] Rebooting in 86400 seconds..