git: 2b25a0ebb48d - stable/15 - socket: remove tautological condition in so_unsplice()

The branch stable/15 has been updated by kevans:

URL: https://cgit.FreeBSD.org/src/commit/?id=2b25a0ebb48dc2340e1e15d1a05b89d7df036b38

commit 2b25a0ebb48dc2340e1e15d1a05b89d7df036b38
Author:     Kyle Evans <[email protected]>
AuthorDate: 2026-06-19 04:03:30 +0000
Commit:     Kyle Evans <[email protected]>
CommitDate: 2026-08-06 23:34:46 +0000

    socket: remove tautological condition in so_unsplice()
    
    so2rele was introduced in 1000cc4a0d3 and it was necessary there, but
    the cleanup in a837d1fe49e0255 rendered it redundant if our own KASSERT
    is to be believed: we've asserted that `so2->so_splice_back == sp` and
    `sp` has been dereferenced above, so there's no condition left where
    we shouldn't release the socket reference at the end.  Indeed, the
    change in so_splice() to NULL out sp->dst removes that possible state of
    a partially constructed splice: if sp->dst is set, it has been ref'd.
    
    Reviewed by:    gallatin, markj
    
    (cherry picked from commit 8a3d28375450946e4b0de239c9239df54c22d298)
---
 sys/kern/uipc_socket.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
index d2ad4e147da5..11d7e794da00 100644
--- a/sys/kern/uipc_socket.c
+++ b/sys/kern/uipc_socket.c
@@ -1773,7 +1773,7 @@ so_unsplice(struct socket *so, bool timeout)
 {
 	struct socket *so2;
 	struct so_splice *sp;
-	bool drain, so2rele;
+	bool drain;
 
 	/*
 	 * First unset SB_SPLICED and hide the splice structure so that
@@ -1818,7 +1818,6 @@ so_unsplice(struct socket *so, bool timeout)
 		KASSERT(so2->so_splice_back == sp,
 		    ("%s: so_splice_back != sp", __func__));
 		so2->so_snd.sb_flags &= ~SB_SPLICED;
-		so2rele = so2->so_splice_back != NULL;
 		so2->so_splice_back = NULL;
 		SOCK_SENDBUF_UNLOCK(so2);
 		SOCK_UNLOCK(so2);
@@ -1864,8 +1863,7 @@ so_unsplice(struct socket *so, bool timeout)
 	sorele(so);
 	if (so2 != NULL) {
 		sowwakeup(so2);
-		if (so2rele)
-			sorele(so2);
+		sorele(so2);
 	}
 	CURVNET_RESTORE();
 	so_splice_free(sp);