lslogins: remove possible memory leaks [coverity scan]

The column can be specified more than once. In this case, the code
will gather the column data multiple times, resulting in a memory
leak.

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/login-utils/lslogins.c b/login-utils/lslogins.c
index a7152737a4c3735313d3fe6add6496f4cfd103a7..54f668af69748217bb24ce42e23e537e7c31ea4d 100644 (file)
--- a/login-utils/lslogins.c
+++ b/login-utils/lslogins.c
@@ -838,13 +838,15 @@ static struct lslogins_user *get_user_info(struct lslogins_control *ctl, const c
        while (n < ncolumns) {
                switch (columns[n++]) {
                case COL_USER:
-                       user->login = xstrdup(pwd->pw_name);
+                       if (!user->login)
+                               user->login = xstrdup(pwd->pw_name);
                        break;
                case COL_UID:
                        user->uid = pwd->pw_uid;
                        break;
                case COL_GROUP:
-                       user->group = xstrdup(grp->gr_name);
+                       if (!grp->gr_name)
+                               user->group = xstrdup(grp->gr_name);
                        break;
                case COL_GID:
                        user->gid = pwd->pw_gid;
@@ -856,15 +858,20 @@ static struct lslogins_user *get_user_info(struct lslogins_control *ctl, const c
                                err(EXIT_FAILURE, _("failed to get supplementary groups"));
                        break;
                case COL_HOME:
-                       user->homedir = xstrdup(pwd->pw_dir);
+                       if (!user->homedir)
+                               user->homedir = xstrdup(pwd->pw_dir);
                        break;
                case COL_SHELL:
-                       user->shell = xstrdup(pwd->pw_shell);
+                       if (!user->shell)
+                               user->shell = xstrdup(pwd->pw_shell);
                        break;
                case COL_GECOS:
-                       user->gecos = xstrdup(pwd->pw_gecos);
+                       if (!user->gecos)
+                               user->gecos = xstrdup(pwd->pw_gecos);
                        break;
                case COL_LAST_LOGIN:
+                       if (user->last_login)
+                               break;
                        if (user_wtmp) {
                                time = user_wtmp->ut_tv.tv_sec;
                                user->last_login = make_time(ctl->time_mode, time);
@@ -876,6 +883,8 @@ static struct lslogins_user *get_user_info(struct lslogins_control *ctl, const c
                        }
                        break;
                case COL_LAST_TTY:
+                       if (user->last_tty)
+                               break;
                        user->last_tty = xcalloc(1, sizeof(user_wtmp->ut_line) + 1);
                        if (user_wtmp) {
                                mem2strcpy(user->last_tty, user_wtmp->ut_line,
@@ -885,6 +894,8 @@ static struct lslogins_user *get_user_info(struct lslogins_control *ctl, const c
                                get_lastlog(ctl, user->uid, user->login, user->last_tty, LASTLOG_LINE);
                        break;
                case COL_LAST_HOSTNAME:
+                       if (user->last_hostname)
+                               break;
                        user->last_hostname = xcalloc(1, sizeof(user_wtmp->ut_host) + 1);
                        if (user_wtmp) {
                                mem2strcpy(user->last_hostname, user_wtmp->ut_host,
@@ -894,13 +905,13 @@ static struct lslogins_user *get_user_info(struct lslogins_control *ctl, const c
                                get_lastlog(ctl, user->uid, user->login, user->last_hostname, LASTLOG_HOST);
                        break;
                case COL_FAILED_LOGIN:
-                       if (user_btmp) {
+                       if (!user->failed_login && user_btmp) {
                                time = user_btmp->ut_tv.tv_sec;
                                user->failed_login = make_time(ctl->time_mode, time);
                        }
                        break;
                case COL_FAILED_TTY:
-                       if (user_btmp) {
+                       if (!user->failed_tty && user_btmp) {
                                user->failed_tty = xmalloc(sizeof(user_btmp->ut_line) + 1);
                                mem2strcpy(user->failed_tty, user_btmp->ut_line,
                                                sizeof(user_btmp->ut_line),
@@ -972,11 +983,11 @@ static struct lslogins_user *get_user_info(struct lslogins_control *ctl, const c
                                                access(_PATH_VAR_NOLOGIN, F_OK) == 0;
                        break;
                case COL_PWD_WARN:
-                       if (shadow && shadow->sp_warn >= 0)
+                       if (!user->pwd_warn && shadow && shadow->sp_warn >= 0)
                                xasprintf(&user->pwd_warn, "%ld", shadow->sp_warn);
                        break;
                case COL_PWD_EXPIR:
-                       if (shadow && shadow->sp_expire >= 0)
+                       if (!user->pwd_expire && shadow && shadow->sp_expire >= 0)
                                user->pwd_expire = make_time(ctl->time_mode == TIME_ISO ?
                                                TIME_ISO_SHORT : ctl->time_mode,
                                                shadow->sp_expire * 86400);
@@ -985,17 +996,17 @@ static struct lslogins_user *get_user_info(struct lslogins_control *ctl, const c
                        /* sp_lstchg is specified in days, showing hours
                         * (especially in non-GMT timezones) would only serve
                         * to confuse */
-                       if (shadow)
+                       if (!user->pwd_ctime && shadow)
                                user->pwd_ctime = make_time(ctl->time_mode == TIME_ISO ?
                                                TIME_ISO_SHORT : ctl->time_mode,
                                                shadow->sp_lstchg * 86400);
                        break;
                case COL_PWD_CTIME_MIN:
-                       if (shadow && shadow->sp_min > 0)
+                       if (user->pwd_ctime_min && shadow && shadow->sp_min > 0)
                                xasprintf(&user->pwd_ctime_min, "%ld", shadow->sp_min);
                        break;
                case COL_PWD_CTIME_MAX:
-                       if (shadow && shadow->sp_max > 0)
+                       if (!user->pwd_ctime_max && shadow && shadow->sp_max > 0)
                                xasprintf(&user->pwd_ctime_max, "%ld", shadow->sp_max);
                        break;
                case COL_SELINUX:
@@ -1006,8 +1017,8 @@ static struct lslogins_user *get_user_info(struct lslogins_control *ctl, const c
                        break;
                case COL_NPROCS:
 #ifdef __linux__
-
-                       xasprintf(&user->nprocs, "%d", get_nprocs(pwd->pw_uid));
+                       if (!user->nprocs)
+                               xasprintf(&user->nprocs, "%d", get_nprocs(pwd->pw_uid));
 #endif
                        break;
                default: