BUG: sleeping function called from invalid context at arch/x86/mm/fault.c:1355 in_atomic(): 0, irqs_disabled(): 0, pid: 6692, name: syz-executor.4 3 locks held by syz-executor.4/6692: #0: 0000000015ce71fc (&table[i].mutex){+.+.}, at: nfnl_lock net/netfilter/nfnetlink.c:62 [inline] #0: 0000000015ce71fc (&table[i].mutex){+.+.}, at: nfnetlink_rcv_msg+0x98d/0xf60 net/netfilter/nfnetlink.c:223 #1: 000000006f21dfd9 (rcu_read_lock){....}, at: ctnetlink_create_conntrack+0x199/0x12c0 net/netfilter/nf_conntrack_netlink.c:1929 #2: 000000001790223a (&mm->mmap_sem){++++}, at: __do_page_fault+0x3e2/0xde0 arch/x86/mm/fault.c:1341 Preemption disabled at: [] rcu_lockdep_current_cpu_online kernel/rcu/tree.c:1076 [inline] [] rcu_lockdep_current_cpu_online+0x32/0x1b0 kernel/rcu/tree.c:1068 CPU: 1 PID: 6692 Comm: syz-executor.4 Not tainted 4.19.140-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 ___might_sleep.cold+0x235/0x250 kernel/sched/core.c:6196 __do_page_fault+0x40d/0xde0 arch/x86/mm/fault.c:1355 overlayfs: unrecognized mount option "nfs_ex" or missing value page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1205 RIP: 0010:0x40 Code: Bad RIP value. RSP: 0018:ffff8882151e7190 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000e611000 RDX: 1ffff11042cbdb3f RSI: ffff8882151e7210 RDI: ffff8882151e7260 RBP: ffff8880913cde00 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000005 R11: 00000000f002e702 R12: 0000000000000000 R13: 0000000000000001 R14: ffff8882165ed9c0 R15: ffff8882151e7210 BUG: unable to handle kernel NULL pointer dereference at 0000000000000040 PGD 21b3ca067 P4D 21b3ca067 PUD 213a68067 PMD 0 overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection. Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 1 PID: 6692 Comm: syz-executor.4 Tainted: G W 4.19.140-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:0x40 Code: Bad RIP value. RSP: 0018:ffff8882151e7190 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000e611000 RDX: 1ffff11042cbdb3f RSI: ffff8882151e7210 RDI: ffff8882151e7260 RBP: ffff8880913cde00 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000005 R11: 00000000f002e702 R12: 0000000000000000 R13: 0000000000000001 R14: ffff8882165ed9c0 R15: ffff8882151e7210 FS: 00007f004ba97700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000016 CR3: 000000021516b000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: Modules linked in: CR2: 0000000000000040 ---[ end trace 53901dac9e12fbd1 ]--- RIP: 0010:0x40 Code: Bad RIP value. RSP: 0018:ffff8882151e7190 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000e611000 RDX: 1ffff11042cbdb3f RSI: ffff8882151e7210 RDI: ffff8882151e7260 RBP: ffff8880913cde00 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000005 R11: 00000000f002e702 R12: 0000000000000000 R13: 0000000000000001 R14: ffff8882165ed9c0 R15: ffff8882151e7210 FS: 00007f004ba97700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1dc9af1db8 CR3: 000000021516b000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400