commit b2c3ee3724900975deaf5eae57640bb0c2d7315e
Author: Andreas Schwab <schwab@suse.de>
Date:   Tue Jun 4 11:01:11 2024 +0200

    Remove memory leak in fdopen (bug 31840)
    
    Deallocate the memory for the FILE structure when seeking to the end fails
    in append mode.
    
    Fixes: ea33158c96 ("Fix offset caching for streams and use it for ftell (BZ #16680)")

diff --git a/libio/iofdopen.c b/libio/iofdopen.c
index 498791b2872f4b93..e3596fa4c91644b7 100644
--- a/libio/iofdopen.c
+++ b/libio/iofdopen.c
@@ -156,7 +156,11 @@ _IO_new_fdopen (int fd, const char *mode)
     {
       off64_t new_pos = _IO_SYSSEEK (&new_f->fp.file, 0, _IO_seek_end);
       if (new_pos == _IO_pos_BAD && errno != ESPIPE)
-	return NULL;
+	{
+	  _IO_un_link (&new_f->fp);
+	  free (new_f);
+	  return NULL;
+	}
     }
   return &new_f->fp.file;
 }