From c4a8762e529dc3f8af89dde5dbcbb82f2a4088a3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= <ludo@gnu.org>
Date: Tue, 17 Jan 2023 11:22:36 +0100
Subject: [PATCH] debug-link: Protect against dangling symlinks.
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Fixes <https://issues.guix.gnu.org/60584>.
Reported by Greg Hogan <code@greghogan.com>
and Sébastien Rey-Coyrehourcq <sebastien.rey-coyrehourcq@univ-rouen.fr>.

* guix/build/debug-link.scm (find-elf-files): Wrap 'elf-file?' call in 'catch'.
---
 guix/build/debug-link.scm | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/guix/build/debug-link.scm b/guix/build/debug-link.scm
index f3284f74c4..80941df2fc 100644
--- a/guix/build/debug-link.scm
+++ b/guix/build/debug-link.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2018 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2018, 2023 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -175,7 +175,15 @@ directories."
                 outputs))
 
   (append-map (lambda (directory)
-                (filter elf-file?
+                (filter (lambda (file)
+                          (catch 'system-error
+                            (lambda ()
+                              (elf-file? file))
+                            (lambda args
+                              ;; FILE might be a dangling symlink.
+                              (if (= ENOENT (system-error-errno args))
+                                  #f
+                                  (apply throw args)))))
                         (with-error-to-port (%make-void-port "w")
                           (lambda ()
                             (find-files directory)))))