[....] Starting OpenBSD Secure Shell server: sshd[ 11.632723] random: sshd: uninitialized urandom read (32 bytes read)
[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
Debian GNU/Linux 7 syzkaller ttyS0
syzkaller login: [ 18.117250] random: sshd: uninitialized urandom read (32 bytes read)
[ 18.318094] audit: type=1400 audit(1569029699.641:6): avc: denied { map } for pid=1759 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
[ 18.361977] random: sshd: uninitialized urandom read (32 bytes read)
[ 18.834047] random: sshd: uninitialized urandom read (32 bytes read)
[ 21.779648] random: sshd: uninitialized urandom read (32 bytes read)
Warning: Permanently added '10.128.0.132' (ECDSA) to the list of known hosts.
[ 27.281589] random: sshd: uninitialized urandom read (32 bytes read)
[ 27.375941] audit: type=1400 audit(1569029708.701:7): avc: denied { map } for pid=1777 comm="syz-executor570" path="/root/syz-executor570500798" dev="sda1" ino=16482 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
[ 28.210724] ==================================================================
[ 28.218219] BUG: KASAN: use-after-free in tcp_init_tso_segs+0x19d/0x1f0
[ 28.224956] Read of size 2 at addr ffff8881d234e7b0 by task syz-executor570/1778
[ 28.232466]
[ 28.234075] CPU: 1 PID: 1778 Comm: syz-executor570 Not tainted 4.14.145+ #0
[ 28.241151] Call Trace:
[ 28.243723] dump_stack+0xca/0x134
[ 28.247239] ? tcp_init_tso_segs+0x19d/0x1f0
[ 28.251708] ? tcp_init_tso_segs+0x19d/0x1f0
[ 28.256097] print_address_description+0x60/0x226
[ 28.260920] ? tcp_init_tso_segs+0x19d/0x1f0
[ 28.265306] ? tcp_init_tso_segs+0x19d/0x1f0
[ 28.269691] __kasan_report.cold+0x1a/0x41
[ 28.273950] ? kvm_guest_cpu_init+0x220/0x220
[ 28.278434] ? tcp_init_tso_segs+0x19d/0x1f0
[ 28.282821] tcp_init_tso_segs+0x19d/0x1f0
[ 28.287035] ? tcp_tso_segs+0x7b/0x1c0
[ 28.290999] tcp_write_xmit+0x15a/0x4730
[ 28.295044] ? memset+0x20/0x40
[ 28.298316] __tcp_push_pending_frames+0xa0/0x230
[ 28.303142] tcp_send_fin+0x154/0xbc0
[ 28.306925] tcp_close+0xc62/0xf40
[ 28.310451] inet_release+0xe9/0x1c0
[ 28.314148] __sock_release+0xd2/0x2c0
[ 28.318027] ? __sock_release+0x2c0/0x2c0
[ 28.322149] sock_close+0x15/0x20
[ 28.325596] __fput+0x25e/0x710
[ 28.328860] task_work_run+0x125/0x1a0
[ 28.332731] do_exit+0x9cb/0x2a20
[ 28.336179] ? mm_update_next_owner+0x610/0x610
[ 28.340836] do_group_exit+0x100/0x2e0
[ 28.344705] SyS_exit_group+0x19/0x20
[ 28.348489] ? do_group_exit+0x2e0/0x2e0
[ 28.352524] do_syscall_64+0x19b/0x520
[ 28.356397] entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ 28.361563] RIP: 0033:0x440618
[ 28.364741] RSP: 002b:00007ffc323b3a28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
[ 28.372439] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000440618
[ 28.379689] RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001
[ 28.386946] RBP: 00000000004c6970 R08: 00000000000000e7 R09: ffffffffffffffd0
[ 28.394193] R10: 0000000020000802 R11: 0000000000000246 R12: 0000000000000001
[ 28.401440] R13: 00000000006d95e0 R14: 0000000000000000 R15: 0000000000000000
[ 28.408721]
[ 28.410354] Allocated by task 1778:
[ 28.413968] __kasan_kmalloc.part.0+0x53/0xc0
[ 28.418460] kmem_cache_alloc+0xee/0x360
[ 28.422523] __alloc_skb+0xea/0x5c0
[ 28.426144] sk_stream_alloc_skb+0xf4/0x8a0
[ 28.430453] tcp_sendmsg_locked+0xf11/0x2f50
[ 28.434838] tcp_sendmsg+0x2b/0x40
[ 28.438366] inet_sendmsg+0x15b/0x520
[ 28.442231] sock_sendmsg+0xb7/0x100
[ 28.445919] SyS_sendto+0x1de/0x2f0
[ 28.449522] do_syscall_64+0x19b/0x520
[ 28.453386] entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ 28.458563] 0xffffffffffffffff
[ 28.461816]
[ 28.463420] Freed by task 1778:
[ 28.466676] __kasan_slab_free+0x164/0x210
[ 28.470894] kmem_cache_free+0xd7/0x3b0
[ 28.474846] kfree_skbmem+0x84/0x110
[ 28.478535] tcp_remove_empty_skb+0x264/0x320
[ 28.483007] tcp_sendmsg_locked+0x1c09/0x2f50
[ 28.487512] tcp_sendmsg+0x2b/0x40
[ 28.491037] inet_sendmsg+0x15b/0x520
[ 28.494812] sock_sendmsg+0xb7/0x100
[ 28.498500] SyS_sendto+0x1de/0x2f0
[ 28.502104] do_syscall_64+0x19b/0x520
[ 28.505998] entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ 28.511165] 0xffffffffffffffff
[ 28.514419]
[ 28.516026] The buggy address belongs to the object at ffff8881d234e780
[ 28.516026] which belongs to the cache skbuff_fclone_cache of size 456
[ 28.529361] The buggy address is located 48 bytes inside of
[ 28.529361] 456-byte region [ffff8881d234e780, ffff8881d234e948)
[ 28.541131] The buggy address belongs to the page:
[ 28.546040] page:ffffea000748d380 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0
[ 28.555993] flags: 0x4000000000010200(slab|head)
[ 28.560746] raw: 4000000000010200 0000000000000000 0000000000000000 00000001800c000c
[ 28.568737] raw: dead000000000100 dead000000000200 ffff8881dab70400 0000000000000000
[ 28.576612] page dumped because: kasan: bad access detected
[ 28.582310]
[ 28.583965] Memory state around the buggy address:
[ 28.588881] ffff8881d234e680: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc
[ 28.596227] ffff8881d234e700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 28.603565] >ffff8881d234e780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 28.610902] ^
[ 28.615805] ffff8881d234e800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 28.623145] ffff8881d234e880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 28.630481] ==================================================================
[ 28.638006] Disabling lock debugging due to kernel taint
[ 28.645678] Kernel panic - not syncing: panic_on_warn set ...
[ 28.645678]
[ 28.653044] CPU: 1 PID: 1778 Comm: syz-executor570 Tainted: G B 4.14.145+ #0
[ 28.661345] Call Trace:
[ 28.663915] dump_stack+0xca/0x134
[ 28.667433] panic+0x1ea/0x3d3
[ 28.670613] ? add_taint.cold+0x16/0x16
[ 28.674564] ? tcp_init_tso_segs+0x19d/0x1f0
[ 28.678947] ? ___preempt_schedule+0x16/0x18
[ 28.683332] ? tcp_init_tso_segs+0x19d/0x1f0
[ 28.687716] end_report+0x43/0x49
[ 28.691145] ? tcp_init_tso_segs+0x19d/0x1f0
[ 28.695536] __kasan_report.cold+0xd/0x41
[ 28.699663] ? kvm_guest_cpu_init+0x220/0x220
[ 28.704137] ? tcp_init_tso_segs+0x19d/0x1f0
[ 28.709401] tcp_init_tso_segs+0x19d/0x1f0
[ 28.713618] ? tcp_tso_segs+0x7b/0x1c0
[ 28.717482] tcp_write_xmit+0x15a/0x4730
[ 28.721524] ? memset+0x20/0x40
[ 28.724784] __tcp_push_pending_frames+0xa0/0x230
[ 28.729757] tcp_send_fin+0x154/0xbc0
[ 28.733687] tcp_close+0xc62/0xf40
[ 28.737215] inet_release+0xe9/0x1c0
[ 28.740912] __sock_release+0xd2/0x2c0
[ 28.744790] ? __sock_release+0x2c0/0x2c0
[ 28.748913] sock_close+0x15/0x20
[ 28.752345] __fput+0x25e/0x710
[ 28.755605] task_work_run+0x125/0x1a0
[ 28.759474] do_exit+0x9cb/0x2a20
[ 28.762919] ? mm_update_next_owner+0x610/0x610
[ 28.767577] do_group_exit+0x100/0x2e0
[ 28.771444] SyS_exit_group+0x19/0x20
[ 28.775225] ? do_group_exit+0x2e0/0x2e0
[ 28.779264] do_syscall_64+0x19b/0x520
[ 28.783132] entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ 28.788305] RIP: 0033:0x440618
[ 28.791471] RSP: 002b:00007ffc323b3a28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
[ 28.799155] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000440618
[ 28.806414] RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001
[ 28.813686] RBP: 00000000004c6970 R08: 00000000000000e7 R09: ffffffffffffffd0
[ 28.820949] R10: 0000000020000802 R11: 0000000000000246 R12: 0000000000000001
[ 28.828197] R13: 00000000006d95e0 R14: 0000000000000000 R15: 0000000000000000
[ 28.836153] Kernel Offset: 0x8c00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[ 28.848534] Rebooting in 86400 seconds..