ip_tables: iptables: counters copy to user failed while replacing table Set syz1 is full, maxelem 0 reached Set syz1 is full, maxelem 0 reached Set syz1 is full, maxelem 0 reached ====================================================== WARNING: possible circular locking dependency detected 4.14.215-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/21989 is trying to acquire lock: (&table[i].mutex){+.+.}, at: [] ip_set_nfnl_put+0x11a/0x310 net/netfilter/ipset/ip_set_core.c:732 but task is already holding lock: (&xt[i].mutex){+.+.}, at: [] xt_find_table_lock+0x38/0x3d0 net/netfilter/x_tables.c:1092 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&xt[i].mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 xt_find_revision+0x88/0x200 net/netfilter/x_tables.c:373 nfnl_compat_get+0x1f7/0x870 net/netfilter/nft_compat.c:678 nfnetlink_rcv_msg+0x9bb/0xc00 net/netfilter/nfnetlink.c:214 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2433 nfnetlink_rcv+0x1ab/0x1da0 net/netfilter/nfnetlink.c:515 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x62e/0xb80 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062 __sys_sendmsg+0xa3/0x120 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0x27/0x40 net/socket.c:2103 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #0 (&table[i].mutex){+.+.}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 ip_set_nfnl_put+0x11a/0x310 net/netfilter/ipset/ip_set_core.c:732 set_target_v1_destroy+0xd7/0x150 net/netfilter/xt_set.c:392 cleanup_entry+0x1fd/0x2d0 net/ipv4/netfilter/ip_tables.c:666 __do_replace+0x38d/0x570 net/ipv4/netfilter/ip_tables.c:1086 do_replace net/ipv4/netfilter/ip_tables.c:1142 [inline] do_ipt_set_ctl+0x256/0x39e net/ipv4/netfilter/ip_tables.c:1674 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x5f/0xb0 net/netfilter/nf_sockopt.c:115 ip_setsockopt net/ipv4/ip_sockglue.c:1255 [inline] ip_setsockopt+0x94/0xb0 net/ipv4/ip_sockglue.c:1240 raw_setsockopt+0xac/0xd0 net/ipv4/raw.c:857 SYSC_setsockopt net/socket.c:1865 [inline] SyS_setsockopt+0x110/0x1e0 net/socket.c:1844 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&xt[i].mutex); lock(&table[i].mutex); lock(&xt[i].mutex); lock(&table[i].mutex); *** DEADLOCK *** 1 lock held by syz-executor.2/21989: #0: (&xt[i].mutex){+.+.}, at: [] xt_find_table_lock+0x38/0x3d0 net/netfilter/x_tables.c:1092 stack backtrace: CPU: 1 PID: 21989 Comm: syz-executor.2 Not tainted 4.14.215-syzkaller #0 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+0x1b2/0x283 lib/dump_stack.c:58 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1905 [inline] check_prevs_add kernel/locking/lockdep.c:2022 [inline] validate_chain kernel/locking/lockdep.c:2464 [inline] __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 ip_set_nfnl_put+0x11a/0x310 net/netfilter/ipset/ip_set_core.c:732 set_target_v1_destroy+0xd7/0x150 net/netfilter/xt_set.c:392 cleanup_entry+0x1fd/0x2d0 net/ipv4/netfilter/ip_tables.c:666 __do_replace+0x38d/0x570 net/ipv4/netfilter/ip_tables.c:1086 do_replace net/ipv4/netfilter/ip_tables.c:1142 [inline] do_ipt_set_ctl+0x256/0x39e net/ipv4/netfilter/ip_tables.c:1674 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x5f/0xb0 net/netfilter/nf_sockopt.c:115 ip_setsockopt net/ipv4/ip_sockglue.c:1255 [inline] ip_setsockopt+0x94/0xb0 net/ipv4/ip_sockglue.c:1240 raw_setsockopt+0xac/0xd0 net/ipv4/raw.c:857 SYSC_setsockopt net/socket.c:1865 [inline] SyS_setsockopt+0x110/0x1e0 net/socket.c:1844 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45e219 RSP: 002b:00007f34dc382c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e219 RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000119c078 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000020000800 R11: 0000000000000246 R12: 000000000119c034 R13: 00007ffea0823cff R14: 00007f34dc3839c0 R15: 000000000119c034 xt_conntrack: cannot load conntrack support for proto=2 xt_conntrack: cannot load conntrack support for proto=2 ptrace attach of "/root/syz-executor.0"[22108] was attempted by "/root/syz-executor.0"[22111] ptrace attach of "/root/syz-executor.2"[22155] was attempted by "/root/syz-executor.2"[22161] ptrace attach of "/root/syz-executor.5"[22188] was attempted by "/root/syz-executor.5"[22190] tmpfs: Bad value 'prefer=static:' for mount option 'mpol' tmpfs: Bad value 'prefer=static:' for mount option 'mpol' netlink: 2 bytes leftover after parsing attributes in process `syz-executor.2'. netlink: 4 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'. FAT-fs (loop0): bogus number of reserved sectors audit: type=1800 audit(1610721407.006:20): pid=22409 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.2" name="ppp" dev="sda1" ino=16401 res=0 FAT-fs (loop0): Can't find a valid FAT filesystem audit: type=1800 audit(1610721407.046:21): pid=22409 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.2" name="ppp" dev="sda1" ino=16401 res=0 FAT-fs (loop0): bogus number of reserved sectors FAT-fs (loop0): Can't find a valid FAT filesystem FAT-fs (loop3): bogus number of reserved sectors FAT-fs (loop3): Can't find a valid FAT filesystem FAT-fs (loop3): bogus number of reserved sectors FAT-fs (loop3): Can't find a valid FAT filesystem netlink: 12 bytes leftover after parsing attributes in process `syz-executor.5'. netlink: 2 bytes leftover after parsing attributes in process `syz-executor.2'. netlink: 2 bytes leftover after parsing attributes in process `syz-executor.2'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'. xt_CT: netfilter: NOTRACK target is deprecated, use CT instead or upgrade iptables netlink: 12 bytes leftover after parsing attributes in process `syz-executor.2'. tmpfs: Bad value 'prefer=static:' for mount option 'mpol' tmpfs: Bad value 'prefer=static:' for mount option 'mpol'