Warning: Permanently added '10.128.10.36' (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 yzkaller login: [ 28.200657] ================================================================== [ 28.208156] BUG: KASAN: use-after-free in refcount_dec_not_one+0x9a/0xc0 [ 28.215126] Read of size 4 at addr ffff8880aea92d98 by task syz-executor141/7984 [ 28.222639] [ 28.224254] CPU: 0 PID: 7984 Comm: syz-executor141 Not tainted 4.14.295-syzkaller #0 [ 28.232108] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 [ 28.241452] Call Trace: [ 28.244031] dump_stack+0x1b2/0x281 [ 28.247643] print_address_description.cold+0x54/0x1d3 [ 28.252898] kasan_report_error.cold+0x8a/0x191 [ 28.257543] ? refcount_dec_not_one+0x9a/0xc0 [ 28.262023] __asan_report_load4_noabort+0x68/0x70 [ 28.266939] ? refcount_dec_not_one+0x9a/0xc0 [ 28.271423] refcount_dec_not_one+0x9a/0xc0 [ 28.275751] refcount_dec_and_mutex_lock+0x1a/0x60 [ 28.280683] nbd_genl_connect+0xce1/0x13e0 [ 28.284901] ? nbd_xmit_timeout+0x500/0x500 [ 28.289207] ? __mutex_lock+0x356/0x1310 [ 28.293246] ? validate_nla+0x192/0x5e0 [ 28.297197] ? nla_parse+0x157/0x1f0 [ 28.300886] genl_family_rcv_msg+0x572/0xb20 [ 28.305274] ? genl_rcv+0x40/0x40 [ 28.308705] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 28.314145] ? trace_hardirqs_on+0x10/0x10 [ 28.318357] genl_rcv_msg+0xaf/0x140 [ 28.322048] netlink_rcv_skb+0x125/0x390 [ 28.326085] ? genl_family_rcv_msg+0xb20/0xb20 [ 28.330640] ? netlink_ack+0x9a0/0x9a0 [ 28.334507] ? lock_acquire+0x170/0x3f0 [ 28.338471] genl_rcv+0x24/0x40 [ 28.341731] netlink_unicast+0x437/0x610 [ 28.345768] ? netlink_sendskb+0xd0/0xd0 [ 28.349810] ? __check_object_size+0x179/0x230 [ 28.354465] netlink_sendmsg+0x648/0xbc0 [ 28.358509] ? nlmsg_notify+0x1b0/0x1b0 [ 28.362456] ? kernel_recvmsg+0x210/0x210 [ 28.366580] ? security_socket_sendmsg+0x83/0xb0 [ 28.371397] ? nlmsg_notify+0x1b0/0x1b0 [ 28.375342] sock_sendmsg+0xb5/0x100 [ 28.379039] ___sys_sendmsg+0x6c8/0x800 [ 28.382995] ? copy_msghdr_from_user+0x3b0/0x3b0 [ 28.387730] ? netlink_dump+0xb90/0xb90 [ 28.391683] ? nlmsg_notify+0x1b0/0x1b0 [ 28.395638] ? security_socket_recvmsg+0x8b/0xc0 [ 28.400378] ? SyS_recvfrom+0x27f/0x340 [ 28.404333] ? SyS_send+0x40/0x40 [ 28.407762] ? vm_insert_page+0x7c0/0x7c0 [ 28.411890] ? __fdget+0x167/0x1f0 [ 28.415405] ? sockfd_lookup_light+0xb2/0x160 [ 28.419875] __sys_sendmsg+0xa3/0x120 [ 28.423654] ? SyS_shutdown+0x160/0x160 [ 28.427605] ? up_read+0x17/0x30 [ 28.430949] ? __do_page_fault+0x159/0xad0 [ 28.435182] SyS_sendmsg+0x27/0x40 [ 28.438695] ? __sys_sendmsg+0x120/0x120 [ 28.442731] do_syscall_64+0x1d5/0x640 [ 28.446595] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 28.451841] RIP: 0033:0x7f6b46daa919 [ 28.455532] RSP: 002b:00007ffc80b8b7c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 28.463212] RAX: ffffffffffffffda RBX: 00000000000f4240 RCX: 00007f6b46daa919 [ 28.470457] RDX: 0000000000000000 RSI: 0000000020000380 RDI: 0000000000000003 [ 28.477715] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 [ 28.484962] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6b46d6db70 [ 28.492215] R13: 0000000000000000 R14: 00007ffc80b8b7f0 R15: 00007ffc80b8b7e0 [ 28.499473] [ 28.501082] Allocated by task 1: [ 28.504447] kasan_kmalloc+0xeb/0x160 [ 28.508230] kmem_cache_alloc_trace+0x131/0x3d0 [ 28.512872] nbd_dev_add+0x7c/0x800 [ 28.516474] nbd_init+0x15b/0x17a [ 28.519917] do_one_initcall+0x88/0x210 [ 28.523895] kernel_init_freeable+0x565/0x626 [ 28.528365] kernel_init+0xd/0x161 [ 28.531880] ret_from_fork+0x24/0x30 [ 28.535564] [ 28.537168] Freed by task 7984: [ 28.540422] kasan_slab_free+0xc3/0x1a0 [ 28.544383] kfree+0xc9/0x250 [ 28.547472] nbd_put.part.0+0x100/0x140 [ 28.551423] nbd_config_put+0x51c/0x6c0 [ 28.555376] nbd_genl_connect+0xcb9/0x13e0 [ 28.559591] genl_family_rcv_msg+0x572/0xb20 [ 28.563972] genl_rcv_msg+0xaf/0x140 [ 28.567682] netlink_rcv_skb+0x125/0x390 [ 28.571725] genl_rcv+0x24/0x40 [ 28.574977] netlink_unicast+0x437/0x610 [ 28.579010] netlink_sendmsg+0x648/0xbc0 [ 28.583044] sock_sendmsg+0xb5/0x100 [ 28.586731] ___sys_sendmsg+0x6c8/0x800 [ 28.590680] __sys_sendmsg+0xa3/0x120 [ 28.594451] SyS_sendmsg+0x27/0x40 [ 28.597968] do_syscall_64+0x1d5/0x640 [ 28.601840] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 28.607002] [ 28.608607] The buggy address belongs to the object at ffff8880aea92cc0 [ 28.608607] which belongs to the cache kmalloc-512 of size 512 [ 28.621241] The buggy address is located 216 bytes inside of [ 28.621241] 512-byte region [ffff8880aea92cc0, ffff8880aea92ec0) [ 28.633092] The buggy address belongs to the page: [ 28.637997] page:ffffea0002baa480 count:1 mapcount:0 mapping:ffff8880aea92040 index:0x0 [ 28.646115] flags: 0xfff00000000100(slab) [ 28.650238] raw: 00fff00000000100 ffff8880aea92040 0000000000000000 0000000100000006 [ 28.658094] raw: ffffea0002ba3120 ffffea0002baa860 ffff88813fe74940 0000000000000000 [ 28.665974] page dumped because: kasan: bad access detected [ 28.671661] [ 28.673265] Memory state around the buggy address: [ 28.678167] ffff8880aea92c80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 28.685499] ffff8880aea92d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 28.692835] >ffff8880aea92d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 28.700174] ^ [ 28.704304] ffff8880aea92e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 28.711636] ffff8880aea92e80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 28.718971] ================================================================== [ 28.726313] Disabling lock debugging due to kernel taint [ 28.734345] Kernel panic - not syncing: panic_on_warn set ... [ 28.734345] [ 28.741720] CPU: 1 PID: 7984 Comm: syz-executor141 Tainted: G B 4.14.295-syzkaller #0 [ 28.750806] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 [ 28.760154] Call Trace: [ 28.762728] dump_stack+0x1b2/0x281 [ 28.766367] panic+0x1f9/0x42d [ 28.769537] ? add_taint.cold+0x16/0x16 [ 28.773499] ? ___preempt_schedule+0x16/0x18 [ 28.777884] kasan_end_report+0x43/0x49 [ 28.781844] kasan_report_error.cold+0xa7/0x191 [ 28.786491] ? refcount_dec_not_one+0x9a/0xc0 [ 28.790964] __asan_report_load4_noabort+0x68/0x70 [ 28.795883] ? refcount_dec_not_one+0x9a/0xc0 [ 28.800351] refcount_dec_not_one+0x9a/0xc0 [ 28.804648] refcount_dec_and_mutex_lock+0x1a/0x60 [ 28.809551] nbd_genl_connect+0xce1/0x13e0 [ 28.813762] ? nbd_xmit_timeout+0x500/0x500 [ 28.818058] ? __mutex_lock+0x356/0x1310 [ 28.822094] ? validate_nla+0x192/0x5e0 [ 28.826040] ? nla_parse+0x157/0x1f0 [ 28.829750] genl_family_rcv_msg+0x572/0xb20 [ 28.834136] ? genl_rcv+0x40/0x40 [ 28.837565] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 28.843110] ? trace_hardirqs_on+0x10/0x10 [ 28.847320] genl_rcv_msg+0xaf/0x140 [ 28.851007] netlink_rcv_skb+0x125/0x390 [ 28.855043] ? genl_family_rcv_msg+0xb20/0xb20 [ 28.859601] ? netlink_ack+0x9a0/0x9a0 [ 28.863551] ? lock_acquire+0x170/0x3f0 [ 28.867514] genl_rcv+0x24/0x40 [ 28.870784] netlink_unicast+0x437/0x610 [ 28.874836] ? netlink_sendskb+0xd0/0xd0 [ 28.878874] ? __check_object_size+0x179/0x230 [ 28.883434] netlink_sendmsg+0x648/0xbc0 [ 28.887479] ? nlmsg_notify+0x1b0/0x1b0 [ 28.891433] ? kernel_recvmsg+0x210/0x210 [ 28.895561] ? security_socket_sendmsg+0x83/0xb0 [ 28.900293] ? nlmsg_notify+0x1b0/0x1b0 [ 28.904241] sock_sendmsg+0xb5/0x100 [ 28.908016] ___sys_sendmsg+0x6c8/0x800 [ 28.911977] ? copy_msghdr_from_user+0x3b0/0x3b0 [ 28.916709] ? netlink_dump+0xb90/0xb90 [ 28.920662] ? nlmsg_notify+0x1b0/0x1b0 [ 28.924616] ? security_socket_recvmsg+0x8b/0xc0 [ 28.929346] ? SyS_recvfrom+0x27f/0x340 [ 28.933296] ? SyS_send+0x40/0x40 [ 28.936727] ? vm_insert_page+0x7c0/0x7c0 [ 28.940852] ? __fdget+0x167/0x1f0 [ 28.944368] ? sockfd_lookup_light+0xb2/0x160 [ 28.948835] __sys_sendmsg+0xa3/0x120 [ 28.952611] ? SyS_shutdown+0x160/0x160 [ 28.956561] ? up_read+0x17/0x30 [ 28.959902] ? __do_page_fault+0x159/0xad0 [ 28.964112] SyS_sendmsg+0x27/0x40 [ 28.967627] ? __sys_sendmsg+0x120/0x120 [ 28.971666] do_syscall_64+0x1d5/0x640 [ 28.975538] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 28.980702] RIP: 0033:0x7f6b46daa919 [ 28.984385] RSP: 002b:00007ffc80b8b7c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 28.992065] RAX: ffffffffffffffda RBX: 00000000000f4240 RCX: 00007f6b46daa919 [ 28.999308] RDX: 0000000000000000 RSI: 0000000020000380 RDI: 0000000000000003 [ 29.006554] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 [ 29.013803] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6b46d6db70 [ 29.021047] R13: 0000000000000000 R14: 00007ffc80b8b7f0 R15: 00007ffc80b8b7e0 [ 29.028452] Kernel Offset: disabled [ 29.032059] Rebooting in 86400 seconds..