On Tue, 27 Oct 2020 20:48:46 +0900 Masahiro Fujiwara wrote:
*_pdp_find() from gtp_encap_recv() would trigger a crash when a peer sends GTP packets while creating new GTP device.
RIP: 0010:gtp1_pdp_find.isra.0+0x68/0x90 [gtp]
<SNIP> Call Trace: <IRQ> gtp_encap_recv+0xc2/0x2e0 [gtp] ? gtp1_pdp_find.isra.0+0x90/0x90 [gtp] udp_queue_rcv_one_skb+0x1fe/0x530 udp_queue_rcv_skb+0x40/0x1b0 udp_unicast_rcv_skb.isra.0+0x78/0x90 __udp4_lib_rcv+0x5af/0xc70 udp_rcv+0x1a/0x20 ip_protocol_deliver_rcu+0xc5/0x1b0 ip_local_deliver_finish+0x48/0x50 ip_local_deliver+0xe5/0xf0 ? ip_protocol_deliver_rcu+0x1b0/0x1b0
gtp_encap_enable() should be called after gtp_hastable_new() otherwise *_pdp_find() will access the uninitialized hash table.
Fixes: 1e3a3abd8b28 ("gtp: make GTP sockets in gtp_newlink optional") Signed-off-by: Masahiro Fujiwara fujiwara.masahiro@gmail.com
Applied, thank you!