audit: type=1400 audit(1569019988.769:47): avc: denied { create } for pid=7511 comm="syz-executor.4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1
==================================================================
BUG: KASAN: use-after-free in tcp_skb_pcount include/net/tcp.h:911 [inline]
BUG: KASAN: use-after-free in tcp_init_tso_segs+0x1ae/0x200 net/ipv4/tcp_output.c:1790
Read of size 2 at addr ffff888099b6ba30 by task syz-executor.2/7523
CPU: 0 PID: 7523 Comm: syz-executor.2 Not tainted 4.14.145 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x138/0x197 lib/dump_stack.c:53
print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252
kasan_report_error mm/kasan/report.c:351 [inline]
kasan_report mm/kasan/report.c:409 [inline]
kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393
__asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:428
tcp_skb_pcount include/net/tcp.h:911 [inline]
tcp_init_tso_segs+0x1ae/0x200 net/ipv4/tcp_output.c:1790
tcp_write_xmit+0x15e/0x4960 net/ipv4/tcp_output.c:2330
audit: type=1400 audit(1569019988.839:48): avc: denied { write } for pid=7511 comm="syz-executor.4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1
__tcp_push_pending_frames+0xa6/0x260 net/ipv4/tcp_output.c:2563
tcp_send_fin+0x17e/0xc40 net/ipv4/tcp_output.c:3115
tcp_shutdown net/ipv4/tcp.c:2117 [inline]
tcp_shutdown+0xe2/0x110 net/ipv4/tcp.c:2102
audit: type=1400 audit(1569019988.849:49): avc: denied { read } for pid=7511 comm="syz-executor.4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1
inet_shutdown+0x178/0x350 net/ipv4/af_inet.c:832
SYSC_shutdown net/socket.c:1917 [inline]
SyS_shutdown+0xe1/0x170 net/socket.c:1908
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459a09
RSP: 002b:00007f2412761c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000030
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459a09
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000004
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f24127626d4
R13: 00000000004c859b R14: 00000000004df290 R15: 00000000ffffffff
Allocated by task 7509:
save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
save_stack+0x45/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459 [inline]
kasan_kmalloc mm/kasan/kasan.c:551 [inline]
kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529
kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:489
kmem_cache_alloc_node+0x144/0x780 mm/slab.c:3642
__alloc_skb+0x9c/0x500 net/core/skbuff.c:193
alloc_skb_fclone include/linux/skbuff.h:1022 [inline]
sk_stream_alloc_skb+0xb3/0x780 net/ipv4/tcp.c:855
tcp_sendmsg_locked+0xf61/0x3200 net/ipv4/tcp.c:1301
tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1457
inet_sendmsg+0x122/0x500 net/ipv4/af_inet.c:762
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xce/0x110 net/socket.c:656
SYSC_sendto+0x206/0x310 net/socket.c:1763
SyS_sendto+0x40/0x50 net/socket.c:1731
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
Freed by task 7509:
save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
save_stack+0x45/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459 [inline]
kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524
__cache_free mm/slab.c:3496 [inline]
kmem_cache_free+0x83/0x2b0 mm/slab.c:3758
kfree_skbmem+0x8d/0x120 net/core/skbuff.c:607
__kfree_skb+0x1e/0x30 net/core/skbuff.c:646
sk_wmem_free_skb include/net/sock.h:1416 [inline]
tcp_remove_empty_skb.part.0+0x231/0x2e0 net/ipv4/tcp.c:929
tcp_remove_empty_skb net/ipv4/tcp.c:925 [inline]
tcp_sendmsg_locked+0x1ced/0x3200 net/ipv4/tcp.c:1435
tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1457
inet_sendmsg+0x122/0x500 net/ipv4/af_inet.c:762
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xce/0x110 net/socket.c:656
SYSC_sendto+0x206/0x310 net/socket.c:1763
SyS_sendto+0x40/0x50 net/socket.c:1731
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
The buggy address belongs to the object at ffff888099b6ba00
which belongs to the cache skbuff_fclone_cache of size 472
The buggy address is located 48 bytes inside of
472-byte region [ffff888099b6ba00, ffff888099b6bbd8)
The buggy address belongs to the page:
page:ffffea000266dac0 count:1 mapcount:0 mapping:ffff888099b6b000 index:0x0
flags: 0x1fffc0000000100(slab)
raw: 01fffc0000000100 ffff888099b6b000 0000000000000000 0000000100000006
raw: ffffea000267a620 ffffea00023fa5a0 ffff88821b75f3c0 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff888099b6b900: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
ffff888099b6b980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888099b6ba00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888099b6ba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888099b6bb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
EXT4-fs (sda1): re-mounted. Opts: init_itable,