====================================================== WARNING: possible circular locking dependency detected 4.19.163-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.1/15669 is trying to acquire lock: 00000000381d9415 ((&q->adapt_timer)){+.-.}, at: arch_local_irq_disable arch/x86/include/asm/paravirt.h:794 [inline] 00000000381d9415 ((&q->adapt_timer)){+.-.}, at: arch_local_irq_save arch/x86/include/asm/paravirt.h:807 [inline] 00000000381d9415 ((&q->adapt_timer)){+.-.}, at: del_timer_sync+0x75/0x270 kernel/time/timer.c:1294 but task is already holding lock: 00000000c4f28ef3 (&qdisc_rx_lock){+.-.}, at: spin_lock_bh include/linux/spinlock.h:334 [inline] 00000000c4f28ef3 (&qdisc_rx_lock){+.-.}, at: sch_tree_lock include/net/sch_generic.h:477 [inline] 00000000c4f28ef3 (&qdisc_rx_lock){+.-.}, at: red_change+0x379/0x1080 net/sched/sch_red.c:230 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&qdisc_rx_lock){+.-.}: spin_lock include/linux/spinlock.h:329 [inline] red_adaptative_timer+0x92/0x5c0 net/sched/sch_red.c:265 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x215/0x260 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:544 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 arch_local_irq_enable arch/x86/include/asm/paravirt.h:799 [inline] preempt_schedule_irq+0xa6/0x140 kernel/sched/core.c:3743 retint_kernel+0x1b/0x2d arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline] dump_stack+0x2da/0x2fe lib/dump_stack.c:123 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0xa/0x14 lib/fault-inject.c:149 __should_failslab+0x115/0x180 mm/failslab.c:32 should_failslab+0x5/0xf mm/slab_common.c:1588 slab_pre_alloc_hook mm/slab.h:424 [inline] slab_alloc mm/slab.c:3383 [inline] kmem_cache_alloc+0x277/0x370 mm/slab.c:3557 integrity_inode_get+0x47/0x260 security/integrity/iint.c:108 process_measurement+0x297/0x1440 security/integrity/ima/ima_main.c:208 ima_file_check+0xb9/0x100 security/integrity/ima/ima_main.c:391 do_last fs/namei.c:3425 [inline] path_openat+0x7e4/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 ((&q->adapt_timer)){+.-.}: del_timer_sync+0xab/0x270 kernel/time/timer.c:1295 red_destroy+0x15/0x60 net/sched/sch_red.c:182 qdisc_destroy+0x180/0x790 net/sched/sch_generic.c:983 red_change+0x514/0x1080 net/sched/sch_red.c:236 qdisc_change net/sched/sch_api.c:1239 [inline] tc_modify_qdisc+0xf6a/0x1a80 net/sched/sch_api.c:1542 rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4778 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:632 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115 __sys_sendmsg net/socket.c:2153 [inline] __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&qdisc_rx_lock); lock((&q->adapt_timer)); lock(&qdisc_rx_lock); lock((&q->adapt_timer)); *** DEADLOCK *** 2 locks held by syz-executor.1/15669: #0: 00000000df70012f (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000df70012f (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4775 #1: 00000000c4f28ef3 (&qdisc_rx_lock){+.-.}, at: spin_lock_bh include/linux/spinlock.h:334 [inline] #1: 00000000c4f28ef3 (&qdisc_rx_lock){+.-.}, at: sch_tree_lock include/net/sch_generic.h:477 [inline] #1: 00000000c4f28ef3 (&qdisc_rx_lock){+.-.}, at: red_change+0x379/0x1080 net/sched/sch_red.c:230 stack backtrace: CPU: 1 PID: 15669 Comm: syz-executor.1 Not tainted 4.19.163-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2fe lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1221 check_prev_add kernel/locking/lockdep.c:1865 [inline] check_prevs_add kernel/locking/lockdep.c:1978 [inline] validate_chain kernel/locking/lockdep.c:2419 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3415 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3907 del_timer_sync+0xab/0x270 kernel/time/timer.c:1295 red_destroy+0x15/0x60 net/sched/sch_red.c:182 qdisc_destroy+0x180/0x790 net/sched/sch_generic.c:983 red_change+0x514/0x1080 net/sched/sch_red.c:236 qdisc_change net/sched/sch_api.c:1239 [inline] tc_modify_qdisc+0xf6a/0x1a80 net/sched/sch_api.c:1542 rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4778 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:632 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115 __sys_sendmsg net/socket.c:2153 [inline] __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45e159 Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fcb3ad25c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045e159 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000007 RBP: 000000000119bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffe74cb6c6f R14: 00007fcb3ad269c0 R15: 000000000119bf8c netlink: 148 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 148 bytes leftover after parsing attributes in process `syz-executor.1'. x_tables: duplicate underflow at hook 1 netlink: 84 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 84 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 84 bytes leftover after parsing attributes in process `syz-executor.3'. audit: type=1804 audit(1608095170.008:172): pid=16215 uid=0 auid=0 ses=4 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir123163571/syzkaller.gy0rZZ/1138/file0" dev="sda1" ino=17927 res=1 netlink: 84 bytes leftover after parsing attributes in process `syz-executor.3'. IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready netlink: 20 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 20 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 20 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 20 bytes leftover after parsing attributes in process `syz-executor.1'.