========================= WARNING: held lock freed! 4.15.0-rc7+ #182 Not tainted ------------------------- syzkaller283912/3501 is freeing memory 000000007d19495e-000000002cd8bde9, with a lock still held there! (sk_lock-AF_INET6){+.+.}, at: [<00000000b627e956>] lock_sock include/net/sock.h:1463 [inline] (sk_lock-AF_INET6){+.+.}, at: [<00000000b627e956>] sctp_wait_for_sndbuf+0x509/0x8d0 net/sctp/socket.c:8147 1 lock held by syzkaller283912/3501: #0: (sk_lock-AF_INET6){+.+.}, at: [<00000000b627e956>] lock_sock include/net/sock.h:1463 [inline] #0: (sk_lock-AF_INET6){+.+.}, at: [<00000000b627e956>] sctp_wait_for_sndbuf+0x509/0x8d0 net/sctp/socket.c:8147 stack backtrace: CPU: 1 PID: 3501 Comm: syzkaller283912 Not tainted 4.15.0-rc7+ #182 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+0x194/0x257 lib/dump_stack.c:53 print_freed_lock_bug kernel/locking/lockdep.c:4379 [inline] debug_check_no_locks_freed+0x32f/0x3c0 kernel/locking/lockdep.c:4412 kmem_cache_free+0x68/0x2a0 mm/slab.c:3743 sk_prot_free net/core/sock.c:1506 [inline] __sk_destruct+0x622/0x910 net/core/sock.c:1590 sk_destruct+0x47/0x80 net/core/sock.c:1598 __sk_free+0xf1/0x2b0 net/core/sock.c:1609 sk_free+0x2a/0x40 net/core/sock.c:1620 sock_put include/net/sock.h:1658 [inline] sctp_association_destroy net/sctp/associola.c:424 [inline] sctp_association_put+0x14c/0x2f0 net/sctp/associola.c:883 sctp_wait_for_sndbuf+0x673/0x8d0 net/sctp/socket.c:8158 sctp_sendmsg+0x28f7/0x33f0 net/sctp/socket.c:1991 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:628 [inline] sock_sendmsg+0xca/0x110 net/socket.c:638 SYSC_sendto+0x361/0x5c0 net/socket.c:1719 SyS_sendto+0x40/0x50 net/socket.c:1687 entry_SYSCALL_64_fastpath+0x23/0x9a RIP: 0033:0x4457e9 RSP: 002b:00007fa645005da8 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000006dac6c RCX: 00000000004457e9 RDX: 0000000000000001 RSI: 000000002010bf14 RDI: 0000000000000004 RBP: 00000000006dac68 R08: 00000000204d9000 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000216 R12: 0000000000000000 R13: 00007ffc779fc65f R14: 00007fa6450069c0 R15: 0000000000000001 ================================================================== BUG: KASAN: use-after-free in debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline] BUG: KASAN: use-after-free in do_raw_spin_lock+0x1e0/0x220 kernel/locking/spinlock_debug.c:112 Read of size 4 at addr ffff8801c0bac08c by task syzkaller283912/3501 CPU: 1 PID: 3501 Comm: syzkaller283912 Not tainted 4.15.0-rc7+ #182 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+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429 debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline] do_raw_spin_lock+0x1e0/0x220 kernel/locking/spinlock_debug.c:112 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline] _raw_spin_lock_bh+0x39/0x40 kernel/locking/spinlock.c:168 spin_lock_bh include/linux/spinlock.h:315 [inline] release_sock+0x74/0x2a0 net/core/sock.c:2787 sctp_sendmsg+0x2993/0x33f0 net/sctp/socket.c:2088 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:628 [inline] sock_sendmsg+0xca/0x110 net/socket.c:638 SYSC_sendto+0x361/0x5c0 net/socket.c:1719 SyS_sendto+0x40/0x50 net/socket.c:1687 entry_SYSCALL_64_fastpath+0x23/0x9a RIP: 0033:0x4457e9 RSP: 002b:00007fa645005da8 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000006dac6c RCX: 00000000004457e9 RDX: 0000000000000001 RSI: 000000002010bf14 RDI: 0000000000000004 RBP: 00000000006dac68 R08: 00000000204d9000 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000216 R12: 0000000000000000 R13: 00007ffc779fc65f R14: 00007fa6450069c0 R15: 0000000000000001 Allocated by task 3506: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3544 sk_prot_alloc+0x65/0x2a0 net/core/sock.c:1465 sk_alloc+0x105/0x1440 net/core/sock.c:1525 sctp_v6_create_accept_sk+0x15a/0x9b0 net/sctp/ipv6.c:667 sctp_accept+0x5c4/0x970 net/sctp/socket.c:4385 inet_accept+0x12c/0x930 net/ipv4/af_inet.c:699 SYSC_accept4+0x38d/0x870 net/socket.c:1543 SyS_accept4 net/socket.c:1494 [inline] SYSC_accept net/socket.c:1577 [inline] SyS_accept+0x26/0x30 net/socket.c:1574 entry_SYSCALL_64_fastpath+0x23/0x9a Freed by task 3501: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3488 [inline] kmem_cache_free+0x83/0x2a0 mm/slab.c:3746 sk_prot_free net/core/sock.c:1506 [inline] __sk_destruct+0x622/0x910 net/core/sock.c:1590 sk_destruct+0x47/0x80 net/core/sock.c:1598 __sk_free+0xf1/0x2b0 net/core/sock.c:1609 sk_free+0x2a/0x40 net/core/sock.c:1620 sock_put include/net/sock.h:1658 [inline] sctp_association_destroy net/sctp/associola.c:424 [inline] sctp_association_put+0x14c/0x2f0 net/sctp/associola.c:883 sctp_wait_for_sndbuf+0x673/0x8d0 net/sctp/socket.c:8158 sctp_sendmsg+0x28f7/0x33f0 net/sctp/socket.c:1991 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:628 [inline] sock_sendmsg+0xca/0x110 net/socket.c:638 SYSC_sendto+0x361/0x5c0 net/socket.c:1719 SyS_sendto+0x40/0x50 net/socket.c:1687 entry_SYSCALL_64_fastpath+0x23/0x9a The buggy address belongs to the object at ffff8801c0bac000 which belongs to the cache SCTPv6 of size 1888 The buggy address is located 140 bytes inside of 1888-byte region [ffff8801c0bac000, ffff8801c0bac760) The buggy address belongs to the page: page:ffffea000702eb00 count:1 mapcount:0 mapping:ffff8801c0bac000 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801c0bac000 0000000000000000 0000000100000002 raw: ffffea00074cabe0 ffffea00072e48a0 ffff8801d32ab500 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c0babf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801c0bac000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801c0bac080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801c0bac100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c0bac180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================