BUG: sleeping function called from invalid context at mm/slab.h:422 in_atomic(): 1, irqs_disabled(): 1, pid: 10045, name: syz-executor.4 3 locks held by syz-executor.4/10045: #0: 00000000f129e6e0 (&ep->mtx){+.+.}, at: __do_sys_epoll_ctl fs/eventpoll.c:2075 [inline] #0: 00000000f129e6e0 (&ep->mtx){+.+.}, at: __se_sys_epoll_ctl+0x5d2/0x2b90 fs/eventpoll.c:1997 #1: 000000003cb9ffb8 (&dev->dev_mutex){+.+.}, at: v4l2_m2m_fop_poll+0x91/0x110 drivers/media/v4l2-core/v4l2-mem2mem.c:1056 #2: 000000004ae29e00 (&(&q->done_lock)->rlock){....}, at: v4l2_m2m_poll+0x140/0x720 drivers/media/v4l2-core/v4l2-mem2mem.c:623 irq event stamp: 374 hardirqs last enabled at (373): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] hardirqs last enabled at (373): [] _raw_spin_unlock_irqrestore+0x79/0xe0 kernel/locking/spinlock.c:184 hardirqs last disabled at (374): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (374): [] _raw_spin_lock_irqsave+0x66/0xc0 kernel/locking/spinlock.c:152 softirqs last enabled at (0): [] copy_process.part.0+0x15b9/0x8260 kernel/fork.c:1856 softirqs last disabled at (0): [<0000000000000000>] (null) Preemption disabled at: [<0000000000000000>] (null) CPU: 1 PID: 10045 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 audit: type=1804 audit(1640417130.423:3): pid=10050 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir715518154/syzkaller.oF0uuQ/5/bus" dev="sda1" ino=13946 res=1 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: 0033:0x7fecb2dfde99 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:00007fecb1773168 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9 RAX: ffffffffffffffda RBX: 00007fecb2f10f60 RCX: 00007fecb2dfde99 RDX: 0000000000000003 RSI: 0000000000000001 RDI: 0000000000000005 RBP: 00007fecb2e57ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000200000c0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffe864a2ef R14: 00007fecb1773300 R15: 0000000000022000 UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2020/09/19 18:44 (1000) netlink: 28 bytes leftover after parsing attributes in process `syz-executor.3'. UBIFS error (pid: 10078): cannot open "/dev/loop2", error -22 UBIFS error (pid: 10093): cannot open "/dev/loop2", error -22 netlink: 28 bytes leftover after parsing attributes in process `syz-executor.3'. UBIFS error (pid: 10128): cannot open "/dev/loop2", error -22 netlink: 28 bytes leftover after parsing attributes in process `syz-executor.3'. SQUASHFS error: squashfs_read_data failed to read block 0x0 device wlan1 entered promiscuous mode squashfs: SQUASHFS error: unable to read squashfs_super_block FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) batman_adv: batadv0: Interface deactivated: batadv_slave_0 batman_adv: batadv0: Removing interface: batadv_slave_0 batman_adv: batadv0: Interface deactivated: batadv_slave_1 batman_adv: batadv0: Removing interface: batadv_slave_1 device bridge_slave_1 left promiscuous mode bridge0: port 2(bridge_slave_1) entered disabled state device bridge_slave_0 left promiscuous mode bridge0: port 1(bridge_slave_0) entered disabled state device veth1_macvtap left promiscuous mode device veth0_macvtap left promiscuous mode device veth1_vlan left promiscuous mode device veth0_vlan left promiscuous mode ieee802154 phy0 wpan0: encryption failed: -22 ieee802154 phy1 wpan1: encryption failed: -22