audit: type=1804 audit(1561978416.765:163): pid=20073 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="bus" dev="sda1" ino=16828 res=1 ================================================================== BUG: KASAN: use-after-free in inet_shutdown+0x2d3/0x350 net/ipv4/af_inet.c:816 Read of size 4 at addr ffff88805d99b1c0 by task syz-executor.1/20071 CPU: 1 PID: 20071 Comm: syz-executor.1 Not tainted 4.14.131 #25 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+0x138/0x19c 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_load4_noabort+0x14/0x20 mm/kasan/report.c:429 inet_shutdown+0x2d3/0x350 net/ipv4/af_inet.c:816 pppol2tp_session_close+0xa0/0xe0 net/l2tp/l2tp_ppp.c:441 l2tp_tunnel_closeall+0x243/0x380 net/l2tp/l2tp_core.c:1340 l2tp_udp_encap_destroy+0x99/0x100 net/l2tp/l2tp_core.c:1366 udp_destroy_sock net/ipv4/udp.c:2330 [inline] udp_destroy_sock+0x10f/0x1a0 net/ipv4/udp.c:2320 sk_common_release+0x6b/0x310 net/core/sock.c:2987 udp_lib_close+0x16/0x20 include/net/udp.h:203 inet_release+0xec/0x1c0 net/ipv4/af_inet.c:425 __sock_release+0xce/0x2b0 net/socket.c:602 sock_close+0x1b/0x30 net/socket.c:1139 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1da/0x220 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007f41f89f0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000459519 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f41f89f16d4 R13: 00000000004f85b2 R14: 00000000004d1370 R15: 00000000ffffffff Allocated by task 20071: 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+0x12e/0x780 mm/slab.c:3552 sock_alloc_inode+0x1d/0x260 net/socket.c:251 alloc_inode+0x64/0x180 fs/inode.c:209 new_inode_pseudo+0x19/0xf0 fs/inode.c:891 sock_alloc+0x41/0x280 net/socket.c:569 __sock_create+0x8f/0x620 net/socket.c:1239 sock_create net/socket.c:1315 [inline] SYSC_socket net/socket.c:1345 [inline] SyS_socket+0xd3/0x170 net/socket.c:1325 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Freed by task 20077: 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 sock_destroy_inode+0x54/0x60 net/socket.c:281 destroy_inode+0xc2/0x120 fs/inode.c:266 evict+0x3e6/0x630 fs/inode.c:571 iput_final fs/inode.c:1516 [inline] iput fs/inode.c:1543 [inline] iput+0x471/0x900 fs/inode.c:1528 dentry_unlink_inode+0x286/0x340 fs/dcache.c:387 __dentry_kill+0x32e/0x580 fs/dcache.c:591 dentry_kill fs/dcache.c:632 [inline] dput.part.0+0x59f/0x750 fs/dcache.c:847 dput+0x20/0x30 fs/dcache.c:811 __fput+0x45f/0x7a0 fs/file_table.c:228 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1da/0x220 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 The buggy address belongs to the object at ffff88805d99b1c0 which belongs to the cache sock_inode_cache of size 992 The buggy address is located 0 bytes inside of 992-byte region [ffff88805d99b1c0, ffff88805d99b5a0) The buggy address belongs to the page: page:ffffea00017666c0 count:1 mapcount:0 mapping:ffff88805d99b1c0 index:0xffff88805d99bffd flags: 0x1fffc0000000100(slab) raw: 01fffc0000000100 ffff88805d99b1c0 ffff88805d99bffd 0000000100000003 raw: ffffea00017668a0 ffffea000173b160 ffff88821b7193c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88805d99b080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805d99b100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805d99b180: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff88805d99b200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805d99b280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== audit: type=1804 audit(1561978417.385:164): pid=20088 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op="invalid_pcr" cause="open_writers" comm="syz-executor.3" name="bus" dev="sda1" ino=16847 res=1 audit: type=1804 audit(1561978417.395:165): pid=20087 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="bus" dev="sda1" ino=16945 res=1 audit: type=1804 audit(1561978417.445:166): pid=20090 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="bus" dev="sda1" ino=16838 res=1