1 files changed, 19 insertions, 13 deletions

diff --git a/src/firejail/fs_trace.c b/src/firejail/fs_trace.c
index dd9abe253..17a7b3d23 100644
--- a/src/firejail/fs_trace.c
+++ b/src/firejail/fs_trace.c
@@ -20,25 +20,31 @@
 #include "firejail.h"
 #include <sys/mount.h>
 #include <sys/stat.h>
-#include <linux/limits.h>
 #include <glob.h>
 #include <dirent.h>
 #include <fcntl.h>
 #include <pwd.h>
 
-void fs_trace_preload(void) {
+// create an empty /etc/ld.so.preload
+void fs_trace_touch_preload(void) {
+        create_empty_file_as_root("/etc/ld.so.preload", S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
+}
+
+void fs_trace_touch_or_store_preload(void) {
         struct stat s;
 
-        // create an empty /etc/ld.so.preload
-        if (stat("/etc/ld.so.preload", &s)) {
-                if (arg_debug)
-                        printf("Creating an empty /etc/ld.so.preload file\n");
-                FILE *fp = fopen("/etc/ld.so.preload", "wxe");
-                if (!fp)
-                        errExit("fopen");
-                SET_PERMS_STREAM(fp, 0, 0, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
-                fclose(fp);
-                fs_logger("touch /etc/ld.so.preload");
+        if (stat("/etc/ld.so.preload", &s) != 0) {
+                fs_trace_touch_preload();
+                return;
+        }
+
+        if (s.st_size == 0)
+                return;
+
+        // create a copy of /etc/ld.so.preload
+        if (copy_file("/etc/ld.so.preload", RUN_LDPRELOAD_FILE, 0, 0, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)) {
+                fprintf(stderr, "Error: cannot copy /etc/ld.so.preload file\n");
+                exit(1);
         }
 }
 
@@ -83,7 +89,7 @@ void fs_trace(void) {
         if (arg_debug)
                 printf("Create the new ld.so.preload file\n");
 
-        FILE *fp = fopen(RUN_LDPRELOAD_FILE, "we");
+        FILE *fp = fopen(RUN_LDPRELOAD_FILE, "ae");
         if (!fp)
                 errExit("fopen");
         const char *prefix = RUN_FIREJAIL_LIB_DIR;