[PATCH 1/2] Cygwin: lockf: Fix adding a new lock over multiple locks

[Takashi Yano]

Previously, adding a new lock by lockf() over multiple existing locks
failed. This is due to a bug that lf_setlock() tries to create a lock
that has already been created. This patch fixes the issue.

Addresses: https://cygwin.com/pipermail/cygwin/2024-October/256528.html
Fixes: a998dd705576 ("* flock.cc: Implement all advisory file locking here.")
Reported-by: Christian Franke <Christian.Franke@t-online.de>
Reviewed-by:
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
---
 winsup/cygwin/flock.cc | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/winsup/cygwin/flock.cc b/winsup/cygwin/flock.cc
index 0f1efa01d..5550b3a5b 100644
--- a/winsup/cygwin/flock.cc
+++ b/winsup/cygwin/flock.cc
@@ -1454,13 +1454,14 @@ lf_setlock (lockf_t *lock, inode_t *node, lockf_t **clean, HANDLE fhdl)
 	  /*
 	   * Add the new lock before overlap.
 	   */
-	  if (needtolink) {
+	  if (needtolink)
+	    {
 	      *prev = lock;
 	      lock->lf_next = overlap;
-	  }
+	      lock->create_lock_obj ();
+	    }
 	  overlap->lf_start = lock->lf_end + 1;
 	  lf_wakelock (overlap, fhdl);
-	  lock->create_lock_obj ();
 	  overlap->create_lock_obj ();
 	  break;
 	}
-- 
2.45.1