[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 35.207043] random: sshd: uninitialized urandom read (32 bytes read) [ 35.533718] kauditd_printk_skb: 9 callbacks suppressed [ 35.533726] audit: type=1400 audit(1569019603.573:35): avc: denied { map } for pid=6810 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 [ 35.576143] random: sshd: uninitialized urandom read (32 bytes read) [ 36.107569] random: sshd: uninitialized urandom read (32 bytes read) [ 36.284686] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.1.0' (ECDSA) to the list of known hosts. [ 41.779931] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 41.899804] audit: type=1400 audit(1569019609.933:36): avc: denied { map } for pid=6822 comm="syz-executor010" path="/root/syz-executor010028892" 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 [ 41.926820] TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. [ 41.939508] ================================================================== [ 41.946972] BUG: KASAN: use-after-free in tcp_init_tso_segs+0x1ae/0x200 [ 41.953738] Read of size 2 at addr ffff88808ff4fcf0 by task syz-executor010/6822 [ 41.961248] [ 41.962916] CPU: 1 PID: 6822 Comm: syz-executor010 Not tainted 4.14.145 #0 [ 41.969994] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.979335] Call Trace: [ 41.981905] dump_stack+0x138/0x197 [ 41.985510] ? snd_hda_codec_new+0xc18/0xd80 [ 41.989924] ? tcp_init_tso_segs+0x1ae/0x200 [ 41.994314] print_address_description.cold+0x7c/0x1dc [ 41.999571] ? tcp_init_tso_segs+0x1ae/0x200 [ 42.003970] kasan_report.cold+0xa9/0x2af [ 42.008196] __asan_report_load2_noabort+0x14/0x20 [ 42.013107] tcp_init_tso_segs+0x1ae/0x200 [ 42.017324] ? tcp_tso_segs+0x7d/0x1c0 [ 42.021203] tcp_write_xmit+0x15e/0x4960 [ 42.025261] ? tcp_v6_md5_lookup+0x23/0x30 [ 42.029486] ? tcp_established_options+0x2c5/0x420 [ 42.034504] ? tcp_current_mss+0x1dc/0x2f0 [ 42.038732] ? __alloc_skb+0x3ee/0x500 [ 42.042602] __tcp_push_pending_frames+0xa6/0x260 [ 42.047438] tcp_send_fin+0x17e/0xc40 [ 42.051232] tcp_close+0xcc8/0xfb0 [ 42.054752] ? lock_acquire+0x16f/0x430 [ 42.058720] ? ip_mc_drop_socket+0x1d6/0x230 [ 42.063107] inet_release+0xec/0x1c0 [ 42.066814] inet6_release+0x53/0x80 [ 42.070530] __sock_release+0xce/0x2b0 [ 42.074399] ? __sock_release+0x2b0/0x2b0 [ 42.078523] sock_close+0x1b/0x30 [ 42.081956] __fput+0x275/0x7a0 [ 42.085219] ____fput+0x16/0x20 [ 42.088478] task_work_run+0x114/0x190 [ 42.092349] do_exit+0x7df/0x2c10 [ 42.095785] ? mm_update_next_owner+0x5d0/0x5d0 [ 42.100445] ? fd_install+0x4d/0x60 [ 42.104060] ? sock_map_fd+0x56/0x80 [ 42.107764] ? SyS_socket+0x103/0x170 [ 42.111546] do_group_exit+0x111/0x330 [ 42.115425] SyS_exit_group+0x1d/0x20 [ 42.119202] ? do_group_exit+0x330/0x330 [ 42.123248] do_syscall_64+0x1e8/0x640 [ 42.127117] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 42.131958] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 42.137129] RIP: 0033:0x43ee88 [ 42.140295] RSP: 002b:00007ffe5bc19c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 42.147991] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ee88 [ 42.155255] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 42.162505] RBP: 00000000004be688 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 42.169815] R10: 0000000020000004 R11: 0000000000000246 R12: 0000000000000001 [ 42.177208] R13: 00000000006d0180 R14: 0000000000000000 R15: 0000000000000000 [ 42.184467] [ 42.186073] Allocated by task 6822: [ 42.189684] save_stack_trace+0x16/0x20 [ 42.193644] save_stack+0x45/0xd0 [ 42.197123] kasan_kmalloc+0xce/0xf0 [ 42.200815] kasan_slab_alloc+0xf/0x20 [ 42.204723] kmem_cache_alloc_node+0x144/0x780 [ 42.209285] __alloc_skb+0x9c/0x500 [ 42.212892] sk_stream_alloc_skb+0xb3/0x780 [ 42.217205] tcp_sendmsg_locked+0xf61/0x3200 [ 42.221611] tcp_sendmsg+0x30/0x50 [ 42.225131] inet_sendmsg+0x122/0x500 [ 42.228910] sock_sendmsg+0xce/0x110 [ 42.232638] SYSC_sendto+0x206/0x310 [ 42.236330] SyS_sendto+0x40/0x50 [ 42.239765] do_syscall_64+0x1e8/0x640 [ 42.243634] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 42.248795] [ 42.250399] Freed by task 6822: [ 42.253668] save_stack_trace+0x16/0x20 [ 42.257631] save_stack+0x45/0xd0 [ 42.261071] kasan_slab_free+0x75/0xc0 [ 42.264952] kmem_cache_free+0x83/0x2b0 [ 42.268921] kfree_skbmem+0x8d/0x120 [ 42.272617] __kfree_skb+0x1e/0x30 [ 42.276230] tcp_remove_empty_skb.part.0+0x231/0x2e0 [ 42.281449] tcp_sendmsg_locked+0x1ced/0x3200 [ 42.285925] tcp_sendmsg+0x30/0x50 [ 42.289441] inet_sendmsg+0x122/0x500 [ 42.293221] sock_sendmsg+0xce/0x110 [ 42.296910] SYSC_sendto+0x206/0x310 [ 42.300669] SyS_sendto+0x40/0x50 [ 42.304100] do_syscall_64+0x1e8/0x640 [ 42.307968] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 42.313132] [ 42.314738] The buggy address belongs to the object at ffff88808ff4fcc0 [ 42.314738] which belongs to the cache skbuff_fclone_cache of size 472 [ 42.328084] The buggy address is located 48 bytes inside of [ 42.328084] 472-byte region [ffff88808ff4fcc0, ffff88808ff4fe98) [ 42.339986] The buggy address belongs to the page: [ 42.344900] page:ffffea00023fd3c0 count:1 mapcount:0 mapping:ffff88808ff4f040 index:0x0 [ 42.353033] flags: 0x1fffc0000000100(slab) [ 42.357267] raw: 01fffc0000000100 ffff88808ff4f040 0000000000000000 0000000100000006 [ 42.365125] raw: ffffea0002a370a0 ffff8880a9e1ce48 ffff88821b75f3c0 0000000000000000 [ 42.372993] page dumped because: kasan: bad access detected [ 42.378777] [ 42.380379] Memory state around the buggy address: [ 42.385295] ffff88808ff4fb80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.392632] ffff88808ff4fc00: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.399970] >ffff88808ff4fc80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 42.407313] ^ [ 42.414422] ffff88808ff4fd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.421759] ffff88808ff4fd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.429108] ================================================================== [ 42.436542] Disabling lock debugging due to kernel taint [ 42.442445] Kernel panic - not syncing: panic_on_warn set ... [ 42.442445] [ 42.449809] CPU: 1 PID: 6822 Comm: syz-executor010 Tainted: G B 4.14.145 #0 [ 42.458017] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.467349] Call Trace: [ 42.469929] dump_stack+0x138/0x197 [ 42.473537] ? tcp_init_tso_segs+0x1ae/0x200 [ 42.477927] panic+0x1f2/0x426 [ 42.481105] ? add_taint.cold+0x16/0x16 [ 42.485057] ? ___preempt_schedule+0x16/0x18 [ 42.489445] kasan_end_report+0x47/0x4f [ 42.493406] kasan_report.cold+0x130/0x2af [ 42.497617] __asan_report_load2_noabort+0x14/0x20 [ 42.502524] tcp_init_tso_segs+0x1ae/0x200 [ 42.506736] ? tcp_tso_segs+0x7d/0x1c0 [ 42.510614] tcp_write_xmit+0x15e/0x4960 [ 42.514655] ? tcp_v6_md5_lookup+0x23/0x30 [ 42.518881] ? tcp_established_options+0x2c5/0x420 [ 42.523801] ? tcp_current_mss+0x1dc/0x2f0 [ 42.528023] ? __alloc_skb+0x3ee/0x500 [ 42.531889] __tcp_push_pending_frames+0xa6/0x260 [ 42.536711] tcp_send_fin+0x17e/0xc40 [ 42.540495] tcp_close+0xcc8/0xfb0 [ 42.544015] ? lock_acquire+0x16f/0x430 [ 42.547968] ? ip_mc_drop_socket+0x1d6/0x230 [ 42.552369] inet_release+0xec/0x1c0 [ 42.556061] inet6_release+0x53/0x80 [ 42.559751] __sock_release+0xce/0x2b0 [ 42.563614] ? __sock_release+0x2b0/0x2b0 [ 42.567736] sock_close+0x1b/0x30 [ 42.571166] __fput+0x275/0x7a0 [ 42.574425] ____fput+0x16/0x20 [ 42.577684] task_work_run+0x114/0x190 [ 42.581551] do_exit+0x7df/0x2c10 [ 42.584985] ? mm_update_next_owner+0x5d0/0x5d0 [ 42.589631] ? fd_install+0x4d/0x60 [ 42.593235] ? sock_map_fd+0x56/0x80 [ 42.596923] ? SyS_socket+0x103/0x170 [ 42.600702] do_group_exit+0x111/0x330 [ 42.604586] SyS_exit_group+0x1d/0x20 [ 42.608374] ? do_group_exit+0x330/0x330 [ 42.612435] do_syscall_64+0x1e8/0x640 [ 42.616298] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 42.621121] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 42.626288] RIP: 0033:0x43ee88 [ 42.629464] RSP: 002b:00007ffe5bc19c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 42.637162] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ee88 [ 42.644427] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 42.651675] RBP: 00000000004be688 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 42.658923] R10: 0000000020000004 R11: 0000000000000246 R12: 0000000000000001 [ 42.666169] R13: 00000000006d0180 R14: 0000000000000000 R15: 0000000000000000 [ 42.674698] Kernel Offset: disabled [ 42.678325] Rebooting in 86400 seconds..