1 files changed, 110 insertions, 60 deletions

diff --git a/src/firejail/pulseaudio.c b/src/firejail/pulseaudio.c
index ce1692ba2..4ddaba7ed 100644
--- a/src/firejail/pulseaudio.c
+++ b/src/firejail/pulseaudio.c
@@ -102,74 +102,124 @@ void pulseaudio_init(void) {
         if (set_perms(RUN_PULSE_DIR, getuid(), getgid(), 0700))
                 errExit("set_perms");
 
-        // create ~/.config directory if necessary
-        char *homeusercfg;
-        if (asprintf(&homeusercfg, "%s/.config", cfg.homedir) == -1)
+        // create ~/.config/pulse directory if not present
+        char *dir1;
+        if (asprintf(&dir1, "%s/.config", cfg.homedir) == -1)
                 errExit("asprintf");
-        create_empty_dir_as_user(homeusercfg, 0700);
-        // set environment variable if creating ~/.config wasn't successful or if it is not a directory owned by the user
-        if (lstat(homeusercfg, &s) != 0 || !S_ISDIR(s.st_mode) || s.st_uid != getuid()) {
-                if (arg_debug)
-                        printf("Setting PULSE_CLIENTCONFIG environment variable\n");
-                if (setenv("PULSE_CLIENTCONFIG", pulsecfg, 1) < 0)
-                        errExit("setenv");
-                free(homeusercfg);
-                free(pulsecfg);
-                return;
+        if (lstat(dir1, &s) == -1) {
+                pid_t child = fork();
+                if (child < 0)
+                        errExit("fork");
+                if (child == 0) {
+                        // drop privileges
+                        drop_privs(0);
+
+                        int rv = mkdir(dir1, 0755);
+                        if (rv == 0) {
+                                if (chmod(dir1, 0755))
+                                        {;} // do nothing
+                        }
+#ifdef HAVE_GCOV
+                        __gcov_flush();
+#endif
+                        _exit(0);
+                }
+                // wait for the child to finish
+                waitpid(child, NULL, 0);
+                fs_logger2("create", dir1);
         }
-        free(homeusercfg);
+        else {
+                // we expect a user owned directory
+                if (!S_ISDIR(s.st_mode) || s.st_uid != getuid()) {
+                        if (S_ISLNK(s.st_mode))
+                                fprintf(stderr, "Error: user .config is a symbolic link\n");
+                        else
+                                fprintf(stderr, "Error: user .config is not a directory owned by the current user\n");
+                        exit(1);
+                }
+        }
+        free(dir1);
+
+        if (asprintf(&dir1, "%s/.config/pulse", cfg.homedir) == -1)
+                errExit("asprintf");
+        if (lstat(dir1, &s) == -1) {
+                pid_t child = fork();
+                if (child < 0)
+                        errExit("fork");
+                if (child == 0) {
+                        // drop privileges
+                        drop_privs(0);
+
+                        int rv = mkdir(dir1, 0700);
+                        if (rv == 0) {
+                                if (chmod(dir1, 0700))
+                                        {;} // do nothing
+                        }
+#ifdef HAVE_GCOV
+                        __gcov_flush();
+#endif
+                        _exit(0);
+                }
+                // wait for the child to finish
+                waitpid(child, NULL, 0);
+                fs_logger2("create", dir1);
+        }
+        else {
+                // we expect a user owned directory
+                if (!S_ISDIR(s.st_mode) || s.st_uid != getuid()) {
+                        if (S_ISLNK(s.st_mode))
+                                fprintf(stderr, "Error: user .config/pulse is a symbolic link\n");
+                        else
+                                fprintf(stderr, "Error: user .config/pulse is not a directory owned by the current user\n");
+                        exit(1);
+                }
+        }
+        free(dir1);
 
-        // create ~/.config/pulse directory if necessary
+        // if we have ~/.config/pulse mount the new directory, else set environment variable.
+        char *homeusercfg;
         if (asprintf(&homeusercfg, "%s/.config/pulse", cfg.homedir) == -1)
                 errExit("asprintf");
-        create_empty_dir_as_user(homeusercfg, 0700);
-        // set environment variable if creating ~/.config/pulse wasn't successful or if it is not a directory owned by the user
-        if (lstat(homeusercfg, &s) != 0 || !S_ISDIR(s.st_mode) || s.st_uid != getuid()) {
-                if (arg_debug)
-                        printf("Setting PULSE_CLIENTCONFIG environment variable\n");
-                if (setenv("PULSE_CLIENTCONFIG", pulsecfg, 1) < 0)
-                        errExit("setenv");
-                free(homeusercfg);
-                free(pulsecfg);
-                return;
+        if (stat(homeusercfg, &s) == 0) {
+                // get a file descriptor for ~/.config/pulse, fails if there is any symlink
+                int fd = safe_fd(homeusercfg, O_PATH|O_DIRECTORY|O_NOFOLLOW|O_CLOEXEC);
+                if (fd == -1)
+                        errExit("safe_fd");
+                // confirm the actual mount destination is owned by the user
+                if (fstat(fd, &s) == -1 || s.st_uid != getuid())
+                        errExit("fstat");
+                // preserve a read-only mount
+                struct statvfs vfs;
+                if (fstatvfs(fd, &vfs) == -1)
+                        errExit("fstatvfs");
+                if ((vfs.f_flag & MS_RDONLY) == MS_RDONLY)
+                        fs_rdonly(RUN_PULSE_DIR);
+                // mount via the link in /proc/self/fd
+                char *proc;
+                if (asprintf(&proc, "/proc/self/fd/%d", fd) == -1)
+                        errExit("asprintf");
+                if (mount(RUN_PULSE_DIR, proc, "none", MS_BIND, NULL) < 0)
+                        errExit("mount pulseaudio");
+                fs_logger2("tmpfs", homeusercfg);
+                free(proc);
+                close(fd);
+                // check /proc/self/mountinfo to confirm the mount is ok
+                MountData *mptr = get_last_mount();
+                if (strcmp(mptr->dir, homeusercfg) != 0 || strcmp(mptr->fstype, "tmpfs") != 0)
+                        errLogExit("invalid pulseaudio mount");
+
+                char *p;
+                if (asprintf(&p, "%s/client.conf", homeusercfg) == -1)
+                        errExit("asprintf");
+                fs_logger2("create", p);
+                free(p);
         }
 
-        // get a file descriptor for ~/.config/pulse, fails if there is any symlink
-        int fd = safe_fd(homeusercfg, O_PATH|O_DIRECTORY|O_NOFOLLOW|O_CLOEXEC);
-        if (fd == -1)
-                errExit("safe_fd");
-        // confirm again the actual mount destination is owned by the user
-        if (fstat(fd, &s) == -1)
-                errExit("fstat");
-        if (s.st_uid != getuid()) {
-                fprintf(stderr, "Error: %s is not owned by the current user\n", homeusercfg);
-                exit(1);
+        else {
+                // set environment
+                if (setenv("PULSE_CLIENTCONFIG", pulsecfg, 1) < 0)
+                        errExit("setenv");
         }
-        // preserve a read-only mount
-        struct statvfs vfs;
-        if (fstatvfs(fd, &vfs) == -1)
-                errExit("fstatvfs");
-        if ((vfs.f_flag & MS_RDONLY) == MS_RDONLY)
-                fs_rdonly(RUN_PULSE_DIR);
-        // mount via the link in /proc/self/fd
-        char *proc;
-        if (asprintf(&proc, "/proc/self/fd/%d", fd) == -1)
-                errExit("asprintf");
-        if (mount(RUN_PULSE_DIR, proc, "none", MS_BIND, NULL) < 0)
-                errExit("mount pulseaudio");
-        free(proc);
-        close(fd);
-        // check /proc/self/mountinfo to confirm the mount is ok
-        MountData *mptr = get_last_mount();
-        if (strcmp(mptr->dir, homeusercfg) != 0 || strcmp(mptr->fstype, "tmpfs") != 0)
-                errLogExit("invalid pulseaudio mount");
-        fs_logger2("tmpfs", homeusercfg);
-
-        char *p;
-        if (asprintf(&p, "%s/client.conf", homeusercfg) == -1)
-                errExit("asprintf");
-        fs_logger2("create", p);
-        free(p);
 
         free(pulsecfg);
         free(homeusercfg);