Warning: Permanently added '10.128.0.175' (ECDSA) to the list of known hosts. executing program [ 34.659321] netlink: 4 bytes leftover after parsing attributes in process `syz-executor321'. [ 34.668179] netlink: 4 bytes leftover after parsing attributes in process `syz-executor321'. [ 34.677954] netlink: 4 bytes leftover after parsing attributes in process `syz-executor321'. [ 34.686816] netlink: 4 bytes leftover after parsing attributes in process `syz-executor321'. [ 34.695931] netlink: 4 bytes leftover after parsing attributes in process `syz-executor321'. executing program [ 34.758384] netlink: 4 bytes leftover after parsing attributes in process `syz-executor321'. [ 34.767353] netlink: 4 bytes leftover after parsing attributes in process `syz-executor321'. [ 34.777460] netlink: 4 bytes leftover after parsing attributes in process `syz-executor321'. [ 34.786536] netlink: 4 bytes leftover after parsing attributes in process `syz-executor321'. [ 34.795727] netlink: 4 bytes leftover after parsing attributes in process `syz-executor321'. executing program executing program executing program executing program executing program executing program [ 34.975025] nbd: nbd0 already in use executing program executing program executing program executing program executing program executing program [ 35.226065] nbd: nbd0 already in use 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 [ 36.265715] nbd: nbd0 already in use executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 36.623762] nbd: nbd0 already in use executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.142519] nbd: nbd0 already in use executing program executing program executing program executing program executing program [ 37.333694] nbd: nbd0 already in use 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 [ 37.834703] nbd: nbd0 already in use executing program executing program executing program [ 38.024215] ================================================================== [ 38.031790] BUG: KASAN: use-after-free in refcount_dec_not_one+0x71/0x1d0 [ 38.038794] Read of size 4 at addr ffff8880b26cd698 by task syz-executor321/8671 [ 38.046302] [ 38.047914] CPU: 1 PID: 8671 Comm: syz-executor321 Not tainted 4.19.192-syzkaller #0 [ 38.055770] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 38.065113] Call Trace: [ 38.067702] dump_stack+0x1fc/0x2ef [ 38.071312] print_address_description.cold+0x54/0x219 [ 38.076567] kasan_report_error.cold+0x8a/0x1b9 [ 38.081250] ? refcount_dec_not_one+0x71/0x1d0 [ 38.085807] kasan_report+0x8f/0xa0 [ 38.089445] ? refcount_dec_not_one+0x71/0x1d0 [ 38.094006] refcount_dec_not_one+0x71/0x1d0 [ 38.098393] ? refcount_dec_and_test_checked+0x20/0x20 [ 38.103823] ? nbd_config_put+0x5da/0x870 [ 38.107948] refcount_dec_and_mutex_lock+0x1c/0x80 [ 38.112877] nbd_genl_connect+0x11ee/0x1630 [ 38.117271] ? nbd_xmit_timeout+0x730/0x730 [ 38.121609] ? __sanitizer_cov_trace_switch+0x4b/0x80 [ 38.126800] ? validate_nla+0x270/0x820 [ 38.130777] ? nla_parse+0x1b2/0x290 [ 38.134658] genl_family_rcv_msg+0x642/0xc40 [ 38.139188] ? genl_rcv+0x40/0x40 [ 38.142625] ? genl_rcv_msg+0x12f/0x160 [ 38.146581] ? mutex_trylock+0x1a0/0x1a0 [ 38.150900] ? __radix_tree_lookup+0x216/0x370 [ 38.155597] genl_rcv_msg+0xbf/0x160 [ 38.159301] netlink_rcv_skb+0x160/0x440 [ 38.163464] ? genl_family_rcv_msg+0xc40/0xc40 [ 38.168249] ? netlink_ack+0xae0/0xae0 [ 38.172167] ? genl_rcv+0x15/0x40 [ 38.175788] genl_rcv+0x24/0x40 [ 38.179183] netlink_unicast+0x4d5/0x690 [ 38.183231] ? netlink_sendskb+0x110/0x110 [ 38.187540] ? _copy_from_iter_full+0x229/0x7c0 [ 38.192193] ? __phys_addr_symbol+0x2c/0x70 [ 38.196511] ? __check_object_size+0x17b/0x3e0 [ 38.201086] netlink_sendmsg+0x6bb/0xc40 [ 38.205134] ? aa_af_perm+0x230/0x230 [ 38.209025] ? nlmsg_notify+0x1a0/0x1a0 [ 38.213117] ? kernel_recvmsg+0x220/0x220 [ 38.217249] ? nlmsg_notify+0x1a0/0x1a0 [ 38.221205] sock_sendmsg+0xc3/0x120 [ 38.224908] ___sys_sendmsg+0x7bb/0x8e0 [ 38.228906] ? copy_msghdr_from_user+0x440/0x440 [ 38.233643] ? __fget+0x32f/0x510 [ 38.237078] ? lock_downgrade+0x720/0x720 [ 38.241203] ? check_preemption_disabled+0x41/0x280 [ 38.246196] ? check_preemption_disabled+0x41/0x280 [ 38.251188] ? __fget+0x356/0x510 [ 38.254729] ? do_dup2+0x450/0x450 [ 38.258247] ? __fdget+0x1d0/0x230 [ 38.261794] __x64_sys_sendmsg+0x132/0x220 [ 38.266211] ? __sys_sendmsg+0x1b0/0x1b0 [ 38.270261] ? __se_sys_futex+0x298/0x3b0 [ 38.274412] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 38.279809] ? trace_hardirqs_off_caller+0x6e/0x210 [ 38.285075] ? do_syscall_64+0x21/0x620 [ 38.289032] do_syscall_64+0xf9/0x620 [ 38.292828] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 38.298119] RIP: 0033:0x4464c9 [ 38.301296] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 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 b8 ff ff ff f7 d8 64 89 01 48 [ 38.320375] RSP: 002b:00007f1d4b8bc318 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 38.328263] RAX: ffffffffffffffda RBX: 00000000004cb428 RCX: 00000000004464c9 [ 38.335514] RDX: 0000000000000080 RSI: 0000000020000540 RDI: 0000000000000004 [ 38.342765] RBP: 00000000004cb420 R08: 0000000000000002 R09: 0000000000000000 [ 38.350016] R10: 000000000000000c R11: 0000000000000246 R12: 00000000004cb42c [ 38.357454] R13: 00007ffe748e0a3f R14: 00007f1d4b8bc400 R15: 0000000000022000 [ 38.364831] [ 38.366444] Allocated by task 8665: [ 38.370058] kmem_cache_alloc_trace+0x12f/0x380 [ 38.374716] nbd_dev_add+0x44/0x890 [ 38.378325] nbd_genl_connect+0x488/0x1630 [ 38.382644] genl_family_rcv_msg+0x642/0xc40 [ 38.387126] genl_rcv_msg+0xbf/0x160 [ 38.390845] netlink_rcv_skb+0x160/0x440 [ 38.395947] genl_rcv+0x24/0x40 [ 38.399326] netlink_unicast+0x4d5/0x690 [ 38.403367] netlink_sendmsg+0x6bb/0xc40 [ 38.407418] sock_sendmsg+0xc3/0x120 [ 38.411151] ___sys_sendmsg+0x7bb/0x8e0 [ 38.415236] __x64_sys_sendmsg+0x132/0x220 [ 38.419455] do_syscall_64+0xf9/0x620 [ 38.423242] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 38.428505] [ 38.430115] Freed by task 8671: [ 38.433382] kfree+0xcc/0x210 [ 38.436473] nbd_put.part.0+0xfe/0x140 [ 38.440342] nbd_config_put+0x6a0/0x870 [ 38.444309] nbd_genl_connect+0x11bb/0x1630 [ 38.448612] genl_family_rcv_msg+0x642/0xc40 [ 38.453003] genl_rcv_msg+0xbf/0x160 [ 38.456819] netlink_rcv_skb+0x160/0x440 [ 38.460885] genl_rcv+0x24/0x40 [ 38.464153] netlink_unicast+0x4d5/0x690 [ 38.468199] netlink_sendmsg+0x6bb/0xc40 [ 38.472239] sock_sendmsg+0xc3/0x120 [ 38.475928] ___sys_sendmsg+0x7bb/0x8e0 [ 38.479886] __x64_sys_sendmsg+0x132/0x220 [ 38.484205] do_syscall_64+0xf9/0x620 [ 38.487984] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 38.493145] [ 38.494748] The buggy address belongs to the object at ffff8880b26cd5c0 [ 38.494748] which belongs to the cache kmalloc-512 of size 512 [ 38.507383] The buggy address is located 216 bytes inside of [ 38.507383] 512-byte region [ffff8880b26cd5c0, ffff8880b26cd7c0) [ 38.519319] The buggy address belongs to the page: [ 38.524239] page:ffffea0002c9b340 count:1 mapcount:0 mapping:ffff88813bff0940 index:0xffff8880b26cdd40 [ 38.533668] flags: 0xfff00000000100(slab) [ 38.537792] raw: 00fff00000000100 ffffea0002a90f48 ffffea0002667e48 ffff88813bff0940 [ 38.545671] raw: ffff8880b26cdd40 ffff8880b26cd0c0 0000000100000005 0000000000000000 [ 38.553547] page dumped because: kasan: bad access detected [ 38.559232] [ 38.560835] Memory state around the buggy address: [ 38.565746] ffff8880b26cd580: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 38.573315] ffff8880b26cd600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 38.580673] >ffff8880b26cd680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 38.588405] ^ [ 38.592547] ffff8880b26cd700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 38.599972] ffff8880b26cd780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 38.607313] ================================================================== [ 38.614768] Disabling lock debugging due to kernel taint [ 38.623907] Kernel panic - not syncing: panic_on_warn set ... [ 38.623907] [ 38.631286] CPU: 0 PID: 8671 Comm: syz-executor321 Tainted: G B 4.19.192-syzkaller #0 [ 38.640555] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 38.650028] Call Trace: [ 38.652784] dump_stack+0x1fc/0x2ef [ 38.656483] panic+0x26a/0x50e [ 38.659779] ? __warn_printk+0xf3/0xf3 [ 38.663659] ? preempt_schedule_common+0x45/0xc0 [ 38.668404] ? ___preempt_schedule+0x16/0x18 [ 38.672932] ? trace_hardirqs_on+0x55/0x210 [ 38.677397] kasan_end_report+0x43/0x49 [ 38.681483] kasan_report_error.cold+0xa7/0x1b9 [ 38.686145] ? refcount_dec_not_one+0x71/0x1d0 [ 38.690733] kasan_report+0x8f/0xa0 [ 38.694493] ? refcount_dec_not_one+0x71/0x1d0 [ 38.699064] refcount_dec_not_one+0x71/0x1d0 [ 38.703468] ? refcount_dec_and_test_checked+0x20/0x20 [ 38.708929] ? nbd_config_put+0x5da/0x870 [ 38.713072] refcount_dec_and_mutex_lock+0x1c/0x80 [ 38.718012] nbd_genl_connect+0x11ee/0x1630 [ 38.722417] ? nbd_xmit_timeout+0x730/0x730 [ 38.726872] ? __sanitizer_cov_trace_switch+0x4b/0x80 [ 38.732071] ? validate_nla+0x270/0x820 [ 38.736035] ? nla_parse+0x1b2/0x290 [ 38.739738] genl_family_rcv_msg+0x642/0xc40 [ 38.744144] ? genl_rcv+0x40/0x40 [ 38.747585] ? genl_rcv_msg+0x12f/0x160 [ 38.751554] ? mutex_trylock+0x1a0/0x1a0 [ 38.755769] ? __radix_tree_lookup+0x216/0x370 [ 38.760339] genl_rcv_msg+0xbf/0x160 [ 38.764041] netlink_rcv_skb+0x160/0x440 [ 38.768088] ? genl_family_rcv_msg+0xc40/0xc40 [ 38.772658] ? netlink_ack+0xae0/0xae0 [ 38.776630] ? genl_rcv+0x15/0x40 [ 38.780064] genl_rcv+0x24/0x40 [ 38.783326] netlink_unicast+0x4d5/0x690 [ 38.787384] ? netlink_sendskb+0x110/0x110 [ 38.791632] ? _copy_from_iter_full+0x229/0x7c0 [ 38.796304] ? __phys_addr_symbol+0x2c/0x70 [ 38.800632] ? __check_object_size+0x17b/0x3e0 [ 38.805203] netlink_sendmsg+0x6bb/0xc40 [ 38.809257] ? aa_af_perm+0x230/0x230 [ 38.813043] ? nlmsg_notify+0x1a0/0x1a0 [ 38.816999] ? kernel_recvmsg+0x220/0x220 [ 38.821132] ? nlmsg_notify+0x1a0/0x1a0 [ 38.825089] sock_sendmsg+0xc3/0x120 [ 38.828783] ___sys_sendmsg+0x7bb/0x8e0 [ 38.832747] ? copy_msghdr_from_user+0x440/0x440 [ 38.837485] ? __fget+0x32f/0x510 [ 38.840920] ? lock_downgrade+0x720/0x720 [ 38.845061] ? check_preemption_disabled+0x41/0x280 [ 38.850064] ? check_preemption_disabled+0x41/0x280 [ 38.855063] ? __fget+0x356/0x510 [ 38.858496] ? do_dup2+0x450/0x450 [ 38.862013] ? __fdget+0x1d0/0x230 [ 38.865536] __x64_sys_sendmsg+0x132/0x220 [ 38.869766] ? __sys_sendmsg+0x1b0/0x1b0 [ 38.873809] ? __se_sys_futex+0x298/0x3b0 [ 38.877937] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 38.883457] ? trace_hardirqs_off_caller+0x6e/0x210 [ 38.888452] ? do_syscall_64+0x21/0x620 [ 38.892407] do_syscall_64+0xf9/0x620 [ 38.896188] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 38.901357] RIP: 0033:0x4464c9 [ 38.904534] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 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 b8 ff ff ff f7 d8 64 89 01 48 [ 38.925064] RSP: 002b:00007f1d4b8bc318 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 38.932753] RAX: ffffffffffffffda RBX: 00000000004cb428 RCX: 00000000004464c9 [ 38.940125] RDX: 0000000000000080 RSI: 0000000020000540 RDI: 0000000000000004 [ 38.947392] RBP: 00000000004cb420 R08: 0000000000000002 R09: 0000000000000000 [ 38.954652] R10: 000000000000000c R11: 0000000000000246 R12: 00000000004cb42c [ 38.962123] R13: 00007ffe748e0a3f R14: 00007f1d4b8bc400 R15: 0000000000022000 [ 38.970065] Kernel Offset: disabled [ 38.973689] Rebooting in 86400 seconds..