========================= WARNING: held lock freed! 4.15.0-rc7+ #170 Not tainted ------------------------- syzkaller266173/3656 is freeing memory 000000004ec5c55a-00000000548139b2, with a lock still held there! (sk_lock-AF_INET6){+.+.}, at: [<00000000ebad632e>] lock_sock include/net/sock.h:1461 [inline] (sk_lock-AF_INET6){+.+.}, at: [<00000000ebad632e>] sctp_wait_for_sndbuf+0x509/0x8d0 net/sctp/socket.c:8056 1 lock held by syzkaller266173/3656: #0: (sk_lock-AF_INET6){+.+.}, at: [<00000000ebad632e>] lock_sock include/net/sock.h:1461 [inline] #0: (sk_lock-AF_INET6){+.+.}, at: [<00000000ebad632e>] sctp_wait_for_sndbuf+0x509/0x8d0 net/sctp/socket.c:8056 stack backtrace: CPU: 1 PID: 3656 Comm: syzkaller266173 Not tainted 4.15.0-rc7+ #170 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:1504 [inline] __sk_destruct+0x622/0x910 net/core/sock.c:1585 sk_destruct+0x47/0x80 net/core/sock.c:1593 __sk_free+0x57/0x230 net/core/sock.c:1601 sk_free+0x2a/0x40 net/core/sock.c:1612 sock_put include/net/sock.h:1656 [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:8067 sctp_sendmsg+0x277d/0x3360 net/sctp/socket.c:1974 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763 sock_sendmsg_nosec net/socket.c:638 [inline] sock_sendmsg+0xca/0x110 net/socket.c:648 SYSC_sendto+0x361/0x5c0 net/socket.c:1729 SyS_sendto+0x40/0x50 net/socket.c:1697 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline] do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129 RIP: 0023:0xf7f89c79 RSP: 002b:00000000f7f641dc EFLAGS: 00000292 ORIG_RAX: 0000000000000171 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000002010bf14 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00000000204d9000 RBP: 000000000000001c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ================================================================== 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 ffff8801bc1bb08c by task syzkaller266173/3656 CPU: 1 PID: 3656 Comm: syzkaller266173 Not tainted 4.15.0-rc7+ #170 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:2777 sctp_sendmsg+0x2c61/0x3360 net/sctp/socket.c:2058 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763 sock_sendmsg_nosec net/socket.c:638 [inline] sock_sendmsg+0xca/0x110 net/socket.c:648 SYSC_sendto+0x361/0x5c0 net/socket.c:1729 SyS_sendto+0x40/0x50 net/socket.c:1697 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline] do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129 RIP: 0023:0xf7f89c79 RSP: 002b:00000000f7f641dc EFLAGS: 00000292 ORIG_RAX: 0000000000000171 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000002010bf14 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00000000204d9000 RBP: 000000000000001c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3657: 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:1463 sk_alloc+0x105/0x1410 net/core/sock.c:1523 sctp_v6_create_accept_sk+0x15a/0x9b0 net/sctp/ipv6.c:667 sctp_accept+0x5c4/0x970 net/sctp/socket.c:4324 inet_accept+0x12c/0x930 net/ipv4/af_inet.c:698 SYSC_accept4+0x38d/0x870 net/socket.c:1553 SyS_accept4+0x2c/0x40 net/socket.c:1504 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline] do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129 Freed by task 3656: 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:1504 [inline] __sk_destruct+0x622/0x910 net/core/sock.c:1585 sk_destruct+0x47/0x80 net/core/sock.c:1593 __sk_free+0x57/0x230 net/core/sock.c:1601 sk_free+0x2a/0x40 net/core/sock.c:1612 sock_put include/net/sock.h:1656 [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:8067 sctp_sendmsg+0x277d/0x3360 net/sctp/socket.c:1974 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763 sock_sendmsg_nosec net/socket.c:638 [inline] sock_sendmsg+0xca/0x110 net/socket.c:648 SYSC_sendto+0x361/0x5c0 net/socket.c:1729 SyS_sendto+0x40/0x50 net/socket.c:1697 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline] do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129 The buggy address belongs to the object at ffff8801bc1bb000 which belongs to the cache SCTPv6 of size 1888 The buggy address is located 140 bytes inside of 1888-byte region [ffff8801bc1bb000, ffff8801bc1bb760) The buggy address belongs to the page: page:ffffea0006f06ec0 count:1 mapcount:0 mapping:ffff8801bc1bb000 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801bc1bb000 0000000000000000 0000000100000002 raw: ffffea0006f09aa0 ffffea00076515e0 ffff8801d2cd1cc0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801bc1baf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801bc1bb000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801bc1bb080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801bc1bb100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801bc1bb180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================