From 98f706de445b464f25220360210a4bcb9cc6c41a Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Thu, 20 Jun 2024 13:56:16 -0700 Subject: af_unix: Define locking order for U_LOCK_SECOND in unix_stream_connect(). While a SOCK_(STREAM|SEQPACKET) socket connect()s to another, we hold two locks of them by unix_state_lock() and unix_state_lock_nested() in unix_stream_connect(). Before unix_state_lock_nested(), the following is guaranteed by checking sk->sk_state: 1. The first socket is TCP_LISTEN 2. The second socket is not the first one 3. Simultaneous connect() must fail So, the client state can be TCP_CLOSE or TCP_LISTEN or TCP_ESTABLISHED. Let's define the expected states as unix_state_lock_cmp_fn() instead of using unix_state_lock_nested(). Note that 2. is detected by debug_spin_lock_before() and 3. cannot be expressed as lock_cmp_fn. Signed-off-by: Kuniyuki Iwashima Signed-off-by: Paolo Abeni --- include/net/af_unix.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/net') diff --git a/include/net/af_unix.h b/include/net/af_unix.h index b6eedf7650da..fd813ad73ab8 100644 --- a/include/net/af_unix.h +++ b/include/net/af_unix.h @@ -98,7 +98,6 @@ struct unix_sock { #define unix_state_unlock(s) spin_unlock(&unix_sk(s)->lock) enum unix_socket_lock_class { U_LOCK_NORMAL, - U_LOCK_SECOND, /* for double locking, see unix_state_double_lock(). */ U_LOCK_DIAG, /* used while dumping icons, see sk_diag_dump_icons(). */ U_LOCK_GC_LISTENER, /* used for listening socket while determining gc * candidates to close a small race window. -- cgit v1.2.3