John Fastabend 3c0bd2b066 bpf: sockmap, fix proto update hook to avoid dup calls ... [ Upstream commit 16b2f26498 ] When sockets are added to a sockmap or sockhash we allocate and init a psock. Then update the proto ops with sock_map_init_proto the flow is sock_hash_update_common sock_map_link psock = sock_map_psock_get_checked() <-returns existing psock sock_map_init_proto(sk, psock) <- updates sk_proto If the socket is already in a map this results in the sock_map_init_proto being called multiple times on the same socket. We do this because when a socket is added to multiple maps this might result in a new set of BPF programs being attached to the socket requiring an updated ops struct. This creates a rule where it must be safe to call psock_update_sk_prot multiple times. When we added a fix for UAF through unix sockets in patch 4dd9a38a753fc we broke this rule by adding a sock_hold in that path to ensure the sock is not released. The result is if a af_unix stream sock is placed in multiple maps it results in a memory leak because we call sock_hold multiple times with only a single sock_put on it. Fixes: 8866730aed ("bpf, sockmap: af_unix stream sockets need to hold ref for pair sock") Reported-by: Xingwei Lee <xrivendell7@gmail.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/r/20231221232327.43678-2-john.fastabend@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>		2024-01-25 15:27:30 -08:00
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af_unix.c	bpf, sockmap: af_unix stream sockets need to hold ref for pair sock	2024-01-10 17:10:32 +01:00
diag.c	af_unix: Get user_ns from in_skb in unix_diag_get_exact().	2022-12-01 10:32:20 +01:00
garbage.c	io_uring/af_unix: defer registered files gc to io_uring release	2022-10-12 16:30:34 -06:00
Kconfig	af_unix: Add OOB support	2021-08-04 09:55:52 +01:00
Makefile	af_unix: Implement ->psock_update_sk_prot()	2021-07-15 18:17:50 -07:00
scm.c	af_unix: Fix data-races around user->unix_inflight.	2023-09-19 12:28:02 +02:00
scm.h	net: split out functions related to registering inflight socket files	2019-02-28 08:24:23 -07:00
sysctl_net_unix.c	af_unix: fix unix_sysctl_register() error path	2022-07-09 12:27:33 +01:00
unix_bpf.c	bpf: sockmap, fix proto update hook to avoid dup calls	2024-01-25 15:27:30 -08:00