Warning: Permanently added '10.128.0.159' (ECDSA) to the list of known hosts. [ 32.373061] random: sshd: uninitialized urandom read (32 bytes read) [ 32.460719] audit: type=1400 audit(1569056517.813:7): avc: denied { map } for pid=1793 comm="syz-executor649" path="/root/syz-executor649938218" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 executing program [ 33.220577] ================================================================== [ 33.228207] BUG: KASAN: use-after-free in tcp_init_tso_segs+0x19d/0x1f0 [ 33.235201] Read of size 2 at addr ffff8881d601c7b0 by task syz-executor649/1794 [ 33.242753] [ 33.244401] CPU: 0 PID: 1794 Comm: syz-executor649 Not tainted 4.14.145+ #0 [ 33.251473] Call Trace: [ 33.254045] dump_stack+0xca/0x134 [ 33.257563] ? tcp_init_tso_segs+0x19d/0x1f0 [ 33.261947] ? tcp_init_tso_segs+0x19d/0x1f0 [ 33.266333] print_address_description+0x60/0x226 [ 33.271150] ? tcp_init_tso_segs+0x19d/0x1f0 [ 33.275558] ? tcp_init_tso_segs+0x19d/0x1f0 [ 33.279942] __kasan_report.cold+0x1a/0x41 [ 33.284176] ? kvm_guest_cpu_init+0x220/0x220 [ 33.288649] ? tcp_init_tso_segs+0x19d/0x1f0 [ 33.293048] tcp_init_tso_segs+0x19d/0x1f0 [ 33.297272] ? tcp_tso_segs+0x7b/0x1c0 [ 33.301139] tcp_write_xmit+0x15a/0x4730 [ 33.305181] ? memset+0x20/0x40 [ 33.308447] __tcp_push_pending_frames+0xa0/0x230 [ 33.313268] tcp_send_fin+0x154/0xbc0 [ 33.317053] tcp_close+0xc62/0xf40 [ 33.320680] inet_release+0xe9/0x1c0 [ 33.324376] __sock_release+0xd2/0x2c0 [ 33.328241] ? __sock_release+0x2c0/0x2c0 [ 33.332378] sock_close+0x15/0x20 [ 33.335809] __fput+0x25e/0x710 [ 33.339072] task_work_run+0x125/0x1a0 [ 33.342948] do_exit+0x9cb/0x2a20 [ 33.346384] ? mm_update_next_owner+0x610/0x610 [ 33.351057] do_group_exit+0x100/0x2e0 [ 33.354932] SyS_exit_group+0x19/0x20 [ 33.358719] ? do_group_exit+0x2e0/0x2e0 [ 33.362760] do_syscall_64+0x19b/0x520 [ 33.366628] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 33.371817] RIP: 0033:0x440618 [ 33.374987] RSP: 002b:00007ffd86fb3bb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 33.382686] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000440618 [ 33.389933] RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001 [ 33.397180] RBP: 00000000004c6970 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 33.404428] R10: 0000000020000800 R11: 0000000000000246 R12: 0000000000000001 [ 33.411676] R13: 00000000006d95e0 R14: 0000000000000000 R15: 0000000000000000 [ 33.418952] [ 33.420558] Allocated by task 1794: [ 33.424212] __kasan_kmalloc.part.0+0x53/0xc0 [ 33.428687] kmem_cache_alloc+0xee/0x360 [ 33.432730] __alloc_skb+0xea/0x5c0 [ 33.436334] sk_stream_alloc_skb+0xf4/0x8a0 [ 33.440631] tcp_sendmsg_locked+0xf11/0x2f50 [ 33.445033] tcp_sendmsg+0x2b/0x40 [ 33.448565] inet_sendmsg+0x15b/0x520 [ 33.452349] sock_sendmsg+0xb7/0x100 [ 33.456037] SyS_sendto+0x1de/0x2f0 [ 33.459641] do_syscall_64+0x19b/0x520 [ 33.463507] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 33.468690] 0xffffffffffffffff [ 33.471942] [ 33.473547] Freed by task 1794: [ 33.476802] __kasan_slab_free+0x164/0x210 [ 33.481012] kmem_cache_free+0xd7/0x3b0 [ 33.484962] kfree_skbmem+0x84/0x110 [ 33.488650] tcp_remove_empty_skb+0x264/0x320 [ 33.493120] tcp_sendmsg_locked+0x1c09/0x2f50 [ 33.497590] tcp_sendmsg+0x2b/0x40 [ 33.501106] inet_sendmsg+0x15b/0x520 [ 33.504902] sock_sendmsg+0xb7/0x100 [ 33.508590] SyS_sendto+0x1de/0x2f0 [ 33.512192] do_syscall_64+0x19b/0x520 [ 33.516054] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 33.521233] 0xffffffffffffffff [ 33.524486] [ 33.526090] The buggy address belongs to the object at ffff8881d601c780 [ 33.526090] which belongs to the cache skbuff_fclone_cache of size 456 [ 33.539415] The buggy address is located 48 bytes inside of [ 33.539415] 456-byte region [ffff8881d601c780, ffff8881d601c948) [ 33.551194] The buggy address belongs to the page: [ 33.556116] page:ffffea0007580700 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 33.566086] flags: 0x4000000000010200(slab|head) [ 33.570820] raw: 4000000000010200 0000000000000000 0000000000000000 00000001800c000c [ 33.578695] raw: dead000000000100 dead000000000200 ffff8881dab70400 0000000000000000 [ 33.586550] page dumped because: kasan: bad access detected [ 33.592233] [ 33.593849] Memory state around the buggy address: [ 33.598769] ffff8881d601c680: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc [ 33.606106] ffff8881d601c700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 33.613453] >ffff8881d601c780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.620802] ^ [ 33.625707] ffff8881d601c800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.633041] ffff8881d601c880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.640391] ================================================================== [ 33.647739] Disabling lock debugging due to kernel taint [ 33.653546] Kernel panic - not syncing: panic_on_warn set ... [ 33.653546] [ 33.661025] CPU: 0 PID: 1794 Comm: syz-executor649 Tainted: G B 4.14.145+ #0 [ 33.669318] Call Trace: [ 33.671885] dump_stack+0xca/0x134 [ 33.675416] panic+0x1ea/0x3d3 [ 33.678582] ? add_taint.cold+0x16/0x16 [ 33.682535] ? tcp_init_tso_segs+0x19d/0x1f0 [ 33.686931] ? ___preempt_schedule+0x16/0x18 [ 33.691318] ? tcp_init_tso_segs+0x19d/0x1f0 [ 33.695700] end_report+0x43/0x49 [ 33.699126] ? tcp_init_tso_segs+0x19d/0x1f0 [ 33.703524] __kasan_report.cold+0xd/0x41 [ 33.707663] ? kvm_guest_cpu_init+0x220/0x220 [ 33.712132] ? tcp_init_tso_segs+0x19d/0x1f0 [ 33.716517] tcp_init_tso_segs+0x19d/0x1f0 [ 33.720729] ? tcp_tso_segs+0x7b/0x1c0 [ 33.724599] tcp_write_xmit+0x15a/0x4730 [ 33.728637] ? memset+0x20/0x40 [ 33.731910] __tcp_push_pending_frames+0xa0/0x230 [ 33.736739] tcp_send_fin+0x154/0xbc0 [ 33.740517] tcp_close+0xc62/0xf40 [ 33.744035] inet_release+0xe9/0x1c0 [ 33.747737] __sock_release+0xd2/0x2c0 [ 33.751604] ? __sock_release+0x2c0/0x2c0 [ 33.755739] sock_close+0x15/0x20 [ 33.759175] __fput+0x25e/0x710 [ 33.762435] task_work_run+0x125/0x1a0 [ 33.766301] do_exit+0x9cb/0x2a20 [ 33.769750] ? mm_update_next_owner+0x610/0x610 [ 33.774415] do_group_exit+0x100/0x2e0 [ 33.778295] SyS_exit_group+0x19/0x20 [ 33.782071] ? do_group_exit+0x2e0/0x2e0 [ 33.786110] do_syscall_64+0x19b/0x520 [ 33.790003] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 33.795185] RIP: 0033:0x440618 [ 33.798351] RSP: 002b:00007ffd86fb3bb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 33.806032] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000440618 [ 33.813278] RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001 [ 33.820525] RBP: 00000000004c6970 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 33.827768] R10: 0000000020000800 R11: 0000000000000246 R12: 0000000000000001 [ 33.835012] R13: 00000000006d95e0 R14: 0000000000000000 R15: 0000000000000000 [ 33.842989] Kernel Offset: 0x39600000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 33.853885] Rebooting in 86400 seconds..