41789: Don't save fd if -1.

We try to move an fd which isn't opend but it will feel.
This needs handling specially in the new code for marking
saved fd's.

2 files changed, 16 insertions, 8 deletions

diff --git a/ChangeLog b/ChangeLog
index 959f7d000..9b1567d23 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2017-09-29  Peter Stephenson  <p.stephenson@samsung.com>
+
+	* 41789: Src/exec.c: Don't try to mark an FD as saved if it
+	couldn't be moved.
+
 2017-09-28  Oliver Kiddle  <opk@zsh.org>
 
 	* 41772: Src/Zle/computil.c, Test/Y03arguments.ztst: fix bug
diff --git a/Src/exec.c b/Src/exec.c
index 0d2dc4ebb..780998b1a 100644
--- a/Src/exec.c
+++ b/Src/exec.c
@@ -2325,16 +2325,19 @@ addfd(int forked, int *save, struct multio **mfds, int fd1, int fd2, int rflag,
 		     * fd1 may already be closed here, so
 		     * ignore bad file descriptor error
 		     */
-		    if (fdN < 0 && errno != EBADF) {
-			zerr("cannot duplicate fd %d: %e", fd1, errno);
-			mfds[fd1] = NULL;
-			closemnodes(mfds);
-			return;
+		    if (fdN < 0) {
+			if (errno != EBADF) {
+			    zerr("cannot duplicate fd %d: %e", fd1, errno);
+			    mfds[fd1] = NULL;
+			    closemnodes(mfds);
+			    return;
+			}
+		    } else {
+			DPUTS(fdtable[fdN] != FDT_INTERNAL,
+			      "Saved file descriptor not marked as internal");
+			fdtable[fdN] |= FDT_SAVED_MASK;
 		    }
 		    save[fd1] = fdN;
-		    DPUTS(fdtable[fdN] != FDT_INTERNAL,
-			  "Saved file descriptor not marked as internal");
-		    fdtable[fdN] |= FDT_SAVED_MASK;
 		}
 	    }
 	}