6.18-stable review patch. If anyone has any objections, please let me know.
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From: Kuniyuki Iwashima kuniyu@google.com
[ Upstream commit 622e8838a29845316668ec2e7648428878df7f9a ]
SCTP_DBG_OBJCNT_INC() is called only when sctp_init_sock() returns 0 after successfully allocating sctp_sk(sk)->ep.
OTOH, SCTP_DBG_OBJCNT_DEC() is called in sctp_close().
The code seems to expect that the socket is always exposed to userspace once SCTP_DBG_OBJCNT_INC() is incremented, but there is a path where the assumption is not true.
In sctp_accept(), sctp_sock_migrate() could fail after sctp_init_sock().
Then, sk_common_release() does not call inet_release() nor sctp_close(). Instead, it calls sk->sk_prot->destroy().
Let's move SCTP_DBG_OBJCNT_DEC() from sctp_close() to sctp_destroy_sock().
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima kuniyu@google.com Acked-by: Xin Long lucien.xin@gmail.com Link: https://patch.msgid.link/20251023231751.4168390-2-kuniyu@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/sctp/socket.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/net/sctp/socket.c b/net/sctp/socket.c index ed8293a342402..d190e75e46454 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1553,8 +1553,6 @@ static void sctp_close(struct sock *sk, long timeout) spin_unlock_bh(&net->sctp.addr_wq_lock);
sock_put(sk); - - SCTP_DBG_OBJCNT_DEC(sock); }
/* Handle EPIPE error. */ @@ -5109,9 +5107,12 @@ static void sctp_destroy_sock(struct sock *sk) sp->do_auto_asconf = 0; list_del(&sp->auto_asconf_list); } + sctp_endpoint_free(sp->ep); + sk_sockets_allocated_dec(sk); sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); + SCTP_DBG_OBJCNT_DEC(sock); }
static void sctp_destruct_sock(struct sock *sk)