private home: don't create unused temporary files

1 files changed, 32 insertions, 21 deletions

diff --git a/src/firejail/fs_home.c b/src/firejail/fs_home.c
index 86e6b0949..010999d7a 100644
--- a/src/firejail/fs_home.c
+++ b/src/firejail/fs_home.c
@@ -111,16 +111,8 @@ static void skel(const char *homedir, uid_t u, gid_t g) {
 
 static int store_xauthority(void) {
         // put a copy of .Xauthority in XAUTHORITY_FILE
-        char *src;
         char *dest = RUN_XAUTHORITY_FILE;
-        // create an empty file as root, and change ownership to user
-        FILE *fp = fopen(dest, "w");
-        if (fp) {
-                fprintf(fp, "\n");
-                SET_PERMS_STREAM(fp, getuid(), getgid(), 0600);
-                fclose(fp);
-        }
-
+        char *src;
         if (asprintf(&src, "%s/.Xauthority", cfg.homedir) == -1)
                 errExit("asprintf");
 
@@ -128,29 +120,34 @@ static int store_xauthority(void) {
         if (stat(src, &s) == 0) {
                 if (is_link(src)) {
                         fwarning("invalid .Xauthority file\n");
+                        free(src);
                         return 0;
                 }
 
+                // create an empty file as root, and change ownership to user
+                FILE *fp = fopen(dest, "w");
+                if (fp) {
+                        fprintf(fp, "\n");
+                        SET_PERMS_STREAM(fp, getuid(), getgid(), 0600);
+                        fclose(fp);
+                }
+                else
+                        errExit("fopen");
+
                 copy_file_as_user(src, dest, getuid(), getgid(), 0600); // regular user
                 fs_logger2("clone", dest);
+                free(src);
                 return 1; // file copied
         }
 
+        free(src);
         return 0;
 }
 
 static int store_asoundrc(void) {
-        // put a copy of .Xauthority in XAUTHORITY_FILE
-        char *src;
+        // put a copy of .asoundrc in ASOUNDRC_FILE
         char *dest = RUN_ASOUNDRC_FILE;
-        // create an empty file as root, and change ownership to user
-        FILE *fp = fopen(dest, "w");
-        if (fp) {
-                fprintf(fp, "\n");
-                SET_PERMS_STREAM(fp, getuid(), getgid(), 0644);
-                fclose(fp);
-        }
-
+        char *src;
         if (asprintf(&src, "%s/.asoundrc", cfg.homedir) == -1)
                 errExit("asprintf");
 
@@ -164,18 +161,30 @@ static int store_asoundrc(void) {
                                 fprintf(stderr, "Error: Cannot access %s\n", src);
                                 exit(1);
                         }
-                        if (strncmp(rp, cfg.homedir, strlen(cfg.homedir)) != 0) {
+                        if (strncmp(rp, cfg.homedir, strlen(cfg.homedir)) != 0 || rp[strlen(cfg.homedir)] != '/') {
                                 fprintf(stderr, "Error: .asoundrc is a symbolic link pointing to a file outside home directory\n");
                                 exit(1);
                         }
                         free(rp);
                 }
 
+                // create an empty file as root, and change ownership to user
+                FILE *fp = fopen(dest, "w");
+                if (fp) {
+                        fprintf(fp, "\n");
+                        SET_PERMS_STREAM(fp, getuid(), getgid(), 0644);
+                        fclose(fp);
+                }
+                else
+                        errExit("fopen");
+
                 copy_file_as_user(src, dest, getuid(), getgid(), 0644); // regular user
                 fs_logger2("clone", dest);
+                free(src);
                 return 1; // file copied
         }
 
+        free(src);
         return 0;
 }
 
@@ -194,13 +203,14 @@ static void copy_xauthority(void) {
 
         copy_file_as_user(src, dest, getuid(), getgid(), S_IRUSR | S_IWUSR); // regular user
         fs_logger2("clone", dest);
+        free(dest);
 
         // delete the temporary file
         unlink(src);
 }
 
 static void copy_asoundrc(void) {
-        // copy XAUTHORITY_FILE in the new home directory
+        // copy ASOUNDRC_FILE in the new home directory
         char *src = RUN_ASOUNDRC_FILE ;
         char *dest;
         if (asprintf(&dest, "%s/.asoundrc", cfg.homedir) == -1)
@@ -214,6 +224,7 @@ static void copy_asoundrc(void) {
 
         copy_file_as_user(src, dest, getuid(), getgid(), S_IRUSR | S_IWUSR); // regular user
         fs_logger2("clone", dest);
+        free(dest);
 
         // delete the temporary file
         unlink(src);