BUG: sleeping function called from invalid context at mm/slab.h:422 in_atomic(): 1, irqs_disabled(): 1, pid: 16401, name: syz-executor.0 3 locks held by syz-executor.0/16401: #0: 00000000c4eee7d9 (&ep->mtx){+.+.}, at: __do_sys_epoll_ctl fs/eventpoll.c:2075 [inline] #0: 00000000c4eee7d9 (&ep->mtx){+.+.}, at: __se_sys_epoll_ctl+0x5d2/0x2b90 fs/eventpoll.c:1997 #1: 000000006a176754 (&dev->dev_mutex){+.+.}, at: v4l2_m2m_fop_poll+0x91/0x110 drivers/media/v4l2-core/v4l2-mem2mem.c:1056 #2: 0000000020c0d13a (&(&q->done_lock)->rlock){....}, at: v4l2_m2m_poll+0x140/0x720 drivers/media/v4l2-core/v4l2-mem2mem.c:623 irq event stamp: 1760 hardirqs last enabled at (1759): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] hardirqs last enabled at (1759): [] _raw_spin_unlock_irqrestore+0x79/0xe0 kernel/locking/spinlock.c:184 hardirqs last disabled at (1760): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (1760): [] _raw_spin_lock_irqsave+0x66/0xc0 kernel/locking/spinlock.c:152 softirqs last enabled at (1580): [] __do_softirq+0x678/0x980 kernel/softirq.c:318 softirqs last disabled at (1541): [] invoke_softirq kernel/softirq.c:372 [inline] softirqs last disabled at (1541): [] irq_exit+0x215/0x260 kernel/softirq.c:412 Preemption disabled at: [<0000000000000000>] (null) CPU: 0 PID: 16401 Comm: syz-executor.0 Not tainted 4.19.211-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/0x2ef lib/dump_stack.c:118 ___might_sleep.cold+0x235/0x250 kernel/sched/core.c:6192 slab_pre_alloc_hook mm/slab.h:422 [inline] slab_alloc mm/slab.c:3383 [inline] kmem_cache_alloc+0x26d/0x370 mm/slab.c:3557 ep_ptable_queue_proc+0xaf/0x390 fs/eventpoll.c:1242 poll_wait include/linux/poll.h:51 [inline] v4l2_m2m_poll+0x633/0x720 drivers/media/v4l2-core/v4l2-mem2mem.c:625 v4l2_m2m_fop_poll+0xa4/0x110 drivers/media/v4l2-core/v4l2-mem2mem.c:1058 v4l2_poll+0x146/0x1f0 drivers/media/v4l2-core/v4l2-dev.c:350 vfs_poll include/linux/poll.h:90 [inline] ep_item_poll+0x14a/0x3e0 fs/eventpoll.c:890 ep_insert fs/eventpoll.c:1479 [inline] __do_sys_epoll_ctl fs/eventpoll.c:2112 [inline] __se_sys_epoll_ctl+0x1b04/0x2b90 fs/eventpoll.c:1997 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f6cc1d23e99 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6cc0699168 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9 RAX: ffffffffffffffda RBX: 00007f6cc1e36f60 RCX: 00007f6cc1d23e99 RDX: 0000000000000003 RSI: 0000000000000001 RDI: 0000000000000004 RBP: 00007f6cc1d7dff1 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000200000c0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff19bff60f R14: 00007f6cc0699300 R15: 0000000000022000 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 netlink: 'syz-executor.3': attribute type 3 has an invalid length. EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue overlayfs: missing 'lowerdir' overlayfs: missing 'lowerdir' EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue xt_CT: No such helper "snmp_trap" nla_parse: 29 callbacks suppressed netlink: 14 bytes leftover after parsing attributes in process `syz-executor.5'. netlink: 14 bytes leftover after parsing attributes in process `syz-executor.4'. EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue netlink: 8 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 14 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 14 bytes leftover after parsing attributes in process `syz-executor.5'. netlink: 14 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 'syz-executor.3': attribute type 1 has an invalid length. netlink: 14 bytes leftover after parsing attributes in process `syz-executor.5'. xt_CT: No such helper "snmp_trap" netlink: 8 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 14 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 14 bytes leftover after parsing attributes in process `syz-executor.5'. xt_CT: No such helper "snmp_trap" xt_CT: No such helper "snmp_trap" platform regulatory.0: Direct firmware load for regulatory.db failed with error -2 kvm: vcpu 0: requested 128 ns lapic timer period limited to 200000 ns platform regulatory.0: Direct firmware load for regulatory.db failed with error -2 kvm: vcpu 0: requested 128 ns lapic timer period limited to 200000 ns sp0: Synchronizing with TNC [U] è` xt_CT: No such helper "snmp_trap" kvm: vcpu 0: requested 128 ns lapic timer period limited to 200000 ns sp0: Synchronizing with TNC [U] è` xt_CT: No such helper "snmp_trap" xt_CT: No such helper "snmp_trap" xt_CT: No such helper "snmp_trap" xt_CT: No such helper "snmp_trap" netlink: 'syz-executor.3': attribute type 7 has an invalid length. xt_CT: No such helper "snmp_trap" audit: type=1804 audit(1641527321.939:630): pid=17368 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.2" name="/root/syzkaller-testdir042384234/syzkaller.HHlpwb/123/bus" dev="sda1" ino=14417 res=1 netlink: 'syz-executor.3': attribute type 7 has an invalid length. audit: type=1800 audit(1641527321.979:631): pid=17368 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="bus" dev="sda1" ino=14417 res=0 xt_CT: No such helper "snmp_trap" audit: type=1804 audit(1641527322.029:632): pid=17372 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.2" name="/root/syzkaller-testdir042384234/syzkaller.HHlpwb/123/bus" dev="sda1" ino=14417 res=1 netlink: 'syz-executor.3': attribute type 7 has an invalid length.