KMemLeak: from mptcp_sk_clone_init() #583
Description
Our CI just reported this potential leak:
unreferenced object 0xffff888119d90c80 (size 3032):
comm "packetdrill", pid 31258, jiffies 4299819414
hex dump (first 32 bytes):
7f 00 00 06 7f 00 00 06 00 00 00 00 ad 97 90 1f ................
0a 00 07 41 00 00 00 00 00 00 00 00 00 00 00 00 ...A............
backtrace (crc 890e4443):
kmem_cache_alloc_noprof (mm/slub.c:4190 (discriminator 1))
sk_prot_alloc.isra.0 (net/core/sock.c:2233 (discriminator 2))
sk_clone_lock (net/core/sock.c:2467)
mptcp_sk_clone_init (net/mptcp/protocol.c:3269)
subflow_syn_recv_sock (net/mptcp/subflow.c:880 (discriminator 1))
tcp_check_req (net/ipv4/tcp_minisocks.c:873)
tcp_v6_rcv (net/ipv6/tcp_ipv6.c:1840)
ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:440)
ip6_input_finish (net/ipv6/ip6_input.c:492)
ip6_input (include/linux/rcupdate.h:869)
ipv6_rcv (include/net/dst.h:474 (discriminator 3))
__netif_receive_skb_one_core (net/core/dev.c:6033)
netif_receive_skb_internal (net/core/dev.c:6239)
netif_receive_skb (net/core/dev.c:6298)
tun_rx_batched.isra.0 (include/linux/bottom_half.h:33 (discriminator 1))
tun_get_user (drivers/net/tun.c:1950)
Similar issues have been seen on NIPA:
- https://netdev-3.bots.linux.dev/vmksft-mptcp-dbg/results/279881/1-mptcp-join-sh/stdout
- https://netdev-3.bots.linux.dev/vmksft-mptcp-dbg/results/280062/1-mptcp-join-sh/stdout
@cpaasch did you manage to reproduce it? A false positive?