X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Flibelogind%2Fsd-bus%2Fbus-creds.c;h=3cb996171ec78d529a286e44edcd57a565fb69cc;hb=ec82d020534270d1979da2d0b27f84e1846b2851;hp=ab48aafccc8653adb4aa7091e5265f27fd0519d8;hpb=c16e820c0af4ce234a53c72789248c3dc8c4d69d;p=elogind.git

diff --git a/src/libelogind/sd-bus/bus-creds.c b/src/libelogind/sd-bus/bus-creds.c
index ab48aafcc..3cb996171 100644
--- a/src/libelogind/sd-bus/bus-creds.c
+++ b/src/libelogind/sd-bus/bus-creds.c
@@ -1,5 +1,3 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
 /***
   This file is part of systemd.
 
@@ -19,20 +17,28 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <stdlib.h>
 #include <linux/capability.h>
+#include <stdlib.h>
 
-#include "util.h"
-#include "formats-util.h"
-#include "capability.h"
-#include "cgroup-util.h"
-#include "fileio.h"
-#include "audit.h"
+#include "alloc-util.h"
+#include "audit-util.h"
+#include "bus-creds.h"
+#include "bus-label.h"
 #include "bus-message.h"
 #include "bus-util.h"
+#include "capability-util.h"
+#include "cgroup-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "format-util.h"
+#include "hexdecoct.h"
+#include "parse-util.h"
+#include "process-util.h"
+#include "string-util.h"
 #include "strv.h"
-#include "bus-creds.h"
-#include "bus-label.h"
+#include "terminal-util.h"
+#include "user-util.h"
+#include "util.h"
 
 enum {
         CAP_OFFSET_INHERITABLE = 0,
@@ -51,8 +57,10 @@ void bus_creds_done(sd_bus_creds *c) {
         free(c->unit);
         free(c->user_unit);
         free(c->slice);
+        free(c->user_slice);
         free(c->unescaped_description);
         free(c->supplementary_gids);
+        free(c->tty);
 
         free(c->well_known_names); /* note that this is an strv, but
                                     * we only free the array, not the
@@ -65,7 +73,9 @@ void bus_creds_done(sd_bus_creds *c) {
 }
 
 _public_ sd_bus_creds *sd_bus_creds_ref(sd_bus_creds *c) {
-        assert_return(c, NULL);
+
+        if (!c)
+                return NULL;
 
         if (c->allocated) {
                 assert(c->n_ref > 0);
@@ -103,11 +113,9 @@ _public_ sd_bus_creds *sd_bus_creds_unref(sd_bus_creds *c) {
                         free(c->cgroup_root);
                         free(c->description);
 
-                        free(c->supplementary_gids);
-                        c->supplementary_gids = NULL;
+                        c->supplementary_gids = mfree(c->supplementary_gids);
 
-                        strv_free(c->well_known_names);
-                        c->well_known_names = NULL;
+                        c->well_known_names = strv_free(c->well_known_names);
 
                         bus_creds_done(c);
 
@@ -124,11 +132,13 @@ _public_ sd_bus_creds *sd_bus_creds_unref(sd_bus_creds *c) {
         return NULL;
 }
 
+#if 0 /// UNNEEDED by elogind
 _public_ uint64_t sd_bus_creds_get_mask(const sd_bus_creds *c) {
         assert_return(c, 0);
 
         return c->mask;
 }
+#endif // 0
 
 _public_ uint64_t sd_bus_creds_get_augmented_mask(const sd_bus_creds *c) {
         assert_return(c, 0);
@@ -148,6 +158,7 @@ sd_bus_creds* bus_creds_new(void) {
         return c;
 }
 
+#if 0 /// UNNEEDED by elogind
 _public_ int sd_bus_creds_new_from_pid(sd_bus_creds **ret, pid_t pid, uint64_t mask) {
         sd_bus_creds *c;
         int r;
@@ -179,6 +190,7 @@ _public_ int sd_bus_creds_new_from_pid(sd_bus_creds **ret, pid_t pid, uint64_t m
         *ret = c;
         return 0;
 }
+#endif // 0
 
 _public_ int sd_bus_creds_get_uid(sd_bus_creds *c, uid_t *uid) {
         assert_return(c, -EINVAL);
@@ -202,6 +214,7 @@ _public_ int sd_bus_creds_get_euid(sd_bus_creds *c, uid_t *euid) {
         return 0;
 }
 
+#if 0 /// UNNEEDED by elogind
 _public_ int sd_bus_creds_get_suid(sd_bus_creds *c, uid_t *suid) {
         assert_return(c, -EINVAL);
         assert_return(suid, -EINVAL);
@@ -235,6 +248,7 @@ _public_ int sd_bus_creds_get_gid(sd_bus_creds *c, gid_t *gid) {
         *gid = c->gid;
         return 0;
 }
+#endif // 0
 
 _public_ int sd_bus_creds_get_egid(sd_bus_creds *c, gid_t *egid) {
         assert_return(c, -EINVAL);
@@ -247,6 +261,7 @@ _public_ int sd_bus_creds_get_egid(sd_bus_creds *c, gid_t *egid) {
         return 0;
 }
 
+#if 0 /// UNNEEDED by elogind
 _public_ int sd_bus_creds_get_sgid(sd_bus_creds *c, gid_t *sgid) {
         assert_return(c, -EINVAL);
         assert_return(sgid, -EINVAL);
@@ -279,6 +294,7 @@ _public_ int sd_bus_creds_get_supplementary_gids(sd_bus_creds *c, const gid_t **
         *gids = c->supplementary_gids;
         return (int) c->n_supplementary_gids;
 }
+#endif // 0
 
 _public_ int sd_bus_creds_get_pid(sd_bus_creds *c, pid_t *pid) {
         assert_return(c, -EINVAL);
@@ -292,6 +308,7 @@ _public_ int sd_bus_creds_get_pid(sd_bus_creds *c, pid_t *pid) {
         return 0;
 }
 
+#if 0 /// UNNEEDED by elogind
 _public_ int sd_bus_creds_get_ppid(sd_bus_creds *c, pid_t *ppid) {
         assert_return(c, -EINVAL);
         assert_return(ppid, -EINVAL);
@@ -299,9 +316,16 @@ _public_ int sd_bus_creds_get_ppid(sd_bus_creds *c, pid_t *ppid) {
         if (!(c->mask & SD_BUS_CREDS_PPID))
                 return -ENODATA;
 
+        /* PID 1 has no parent process. Let's distinguish the case of
+         * not knowing and not having a parent process by the returned
+         * error code. */
+        if (c->ppid == 0)
+                return -ENXIO;
+
         *ppid = c->ppid;
         return 0;
 }
+#endif // 0
 
 _public_ int sd_bus_creds_get_tid(sd_bus_creds *c, pid_t *tid) {
         assert_return(c, -EINVAL);
@@ -326,6 +350,7 @@ _public_ int sd_bus_creds_get_selinux_context(sd_bus_creds *c, const char **ret)
         return 0;
 }
 
+#if 0 /// UNNEEDED by elogind
 _public_ int sd_bus_creds_get_comm(sd_bus_creds *c, const char **ret) {
         assert_return(c, -EINVAL);
         assert_return(ret, -EINVAL);
@@ -357,7 +382,9 @@ _public_ int sd_bus_creds_get_exe(sd_bus_creds *c, const char **ret) {
         if (!(c->mask & SD_BUS_CREDS_EXE))
                 return -ENODATA;
 
-        assert(c->exe);
+        if (!c->exe)
+                return -ENXIO;
+
         *ret = c->exe;
         return 0;
 }
@@ -375,6 +402,8 @@ _public_ int sd_bus_creds_get_cgroup(sd_bus_creds *c, const char **ret) {
 }
 
 _public_ int sd_bus_creds_get_unit(sd_bus_creds *c, const char **ret) {
+        int r;
+
         assert_return(c, -EINVAL);
         assert_return(ret, -EINVAL);
 
@@ -383,14 +412,25 @@ _public_ int sd_bus_creds_get_unit(sd_bus_creds *c, const char **ret) {
 
         assert(c->cgroup);
 
-        if (!c->unit)
-                return -ESRCH;
+        if (!c->unit) {
+                const char *shifted;
+
+                r = cg_shift_path(c->cgroup, c->cgroup_root, &shifted);
+                if (r < 0)
+                        return r;
+
+                r = cg_path_get_unit(shifted, (char**) &c->unit);
+                if (r < 0)
+                        return r;
+        }
 
         *ret = c->unit;
         return 0;
 }
 
 _public_ int sd_bus_creds_get_user_unit(sd_bus_creds *c, const char **ret) {
+        int r;
+
         assert_return(c, -EINVAL);
         assert_return(ret, -EINVAL);
 
@@ -399,14 +439,25 @@ _public_ int sd_bus_creds_get_user_unit(sd_bus_creds *c, const char **ret) {
 
         assert(c->cgroup);
 
-        if (!c->user_unit)
-                return -ESRCH;
+        if (!c->user_unit) {
+                const char *shifted;
+
+                r = cg_shift_path(c->cgroup, c->cgroup_root, &shifted);
+                if (r < 0)
+                        return r;
+
+                r = cg_path_get_user_unit(shifted, (char**) &c->user_unit);
+                if (r < 0)
+                        return r;
+        }
 
         *ret = c->user_unit;
         return 0;
 }
 
 _public_ int sd_bus_creds_get_slice(sd_bus_creds *c, const char **ret) {
+        int r;
+
         assert_return(c, -EINVAL);
         assert_return(ret, -EINVAL);
 
@@ -415,13 +466,50 @@ _public_ int sd_bus_creds_get_slice(sd_bus_creds *c, const char **ret) {
 
         assert(c->cgroup);
 
-        if (!c->slice)
-                return -ESRCH;
+        if (!c->slice) {
+                const char *shifted;
+
+                r = cg_shift_path(c->cgroup, c->cgroup_root, &shifted);
+                if (r < 0)
+                        return r;
+
+                r = cg_path_get_slice(shifted, (char**) &c->slice);
+                if (r < 0)
+                        return r;
+        }
 
         *ret = c->slice;
         return 0;
 }
 
+_public_ int sd_bus_creds_get_user_slice(sd_bus_creds *c, const char **ret) {
+        int r;
+
+        assert_return(c, -EINVAL);
+        assert_return(ret, -EINVAL);
+
+        if (!(c->mask & SD_BUS_CREDS_USER_SLICE))
+                return -ENODATA;
+
+        assert(c->cgroup);
+
+        if (!c->user_slice) {
+                const char *shifted;
+
+                r = cg_shift_path(c->cgroup, c->cgroup_root, &shifted);
+                if (r < 0)
+                        return r;
+
+                r = cg_path_get_user_slice(shifted, (char**) &c->user_slice);
+                if (r < 0)
+                        return r;
+        }
+
+        *ret = c->user_slice;
+        return 0;
+}
+#endif // 0
+
 _public_ int sd_bus_creds_get_session(sd_bus_creds *c, const char **ret) {
         int r;
 
@@ -436,10 +524,13 @@ _public_ int sd_bus_creds_get_session(sd_bus_creds *c, const char **ret) {
         if (!c->session) {
                 const char *shifted;
 
+                log_debug_elogind("Shifting cgroup \"%s\", root \"%s\"",
+                                  c->cgroup, c->cgroup_root ? c->cgroup_root : "NULL");
                 r = cg_shift_path(c->cgroup, c->cgroup_root, &shifted);
                 if (r < 0)
                         return r;
 
+                log_debug_elogind("Shifted: \"%s\"", shifted);
                 r = cg_path_get_session(shifted, (char**) &c->session);
                 if (r < 0)
                         return r;
@@ -465,7 +556,12 @@ _public_ int sd_bus_creds_get_owner_uid(sd_bus_creds *c, uid_t *uid) {
         if (r < 0)
                 return r;
 
-        return -ESRCH;
+#if 0 /// elogind does not support systemd slices
+        return cg_path_get_owner_uid(shifted, uid);
+#else
+        *uid = c->uid;
+        return 0;
+#endif // 0
 }
 
 _public_ int sd_bus_creds_get_cmdline(sd_bus_creds *c, char ***cmdline) {
@@ -474,8 +570,8 @@ _public_ int sd_bus_creds_get_cmdline(sd_bus_creds *c, char ***cmdline) {
         if (!(c->mask & SD_BUS_CREDS_CMDLINE))
                 return -ENODATA;
 
-        assert_return(c->cmdline, -ESRCH);
-        assert(c->cmdline);
+        if (!c->cmdline)
+                return -ENXIO;
 
         if (!c->cmdline_array) {
                 c->cmdline_array = strv_parse_nulstr(c->cmdline, c->cmdline_size);
@@ -494,6 +590,9 @@ _public_ int sd_bus_creds_get_audit_session_id(sd_bus_creds *c, uint32_t *sessio
         if (!(c->mask & SD_BUS_CREDS_AUDIT_SESSION_ID))
                 return -ENODATA;
 
+        if (c->audit_session_id == AUDIT_SESSION_INVALID)
+                return -ENXIO;
+
         *sessionid = c->audit_session_id;
         return 0;
 }
@@ -505,10 +604,28 @@ _public_ int sd_bus_creds_get_audit_login_uid(sd_bus_creds *c, uid_t *uid) {
         if (!(c->mask & SD_BUS_CREDS_AUDIT_LOGIN_UID))
                 return -ENODATA;
 
+        if (c->audit_login_uid == UID_INVALID)
+                return -ENXIO;
+
         *uid = c->audit_login_uid;
         return 0;
 }
 
+_public_ int sd_bus_creds_get_tty(sd_bus_creds *c, const char **ret) {
+        assert_return(c, -EINVAL);
+        assert_return(ret, -EINVAL);
+
+        if (!(c->mask & SD_BUS_CREDS_TTY))
+                return -ENODATA;
+
+        if (!c->tty)
+                return -ENXIO;
+
+        *ret = c->tty;
+        return 0;
+}
+
+#if 0 /// UNNEEDED by elogind
 _public_ int sd_bus_creds_get_unique_name(sd_bus_creds *c, const char **unique_name) {
         assert_return(c, -EINVAL);
         assert_return(unique_name, -EINVAL);
@@ -571,6 +688,7 @@ _public_ int sd_bus_creds_get_description(sd_bus_creds *c, const char **ret) {
         *ret = c->unescaped_description;
         return 0;
 }
+#endif // 0
 
 static int has_cap(sd_bus_creds *c, unsigned offset, int capability) {
         size_t sz;
@@ -597,6 +715,7 @@ _public_ int sd_bus_creds_has_effective_cap(sd_bus_creds *c, int capability) {
         return has_cap(c, CAP_OFFSET_EFFECTIVE, capability);
 }
 
+#if 0 /// UNNEEDED by elogind
 _public_ int sd_bus_creds_has_permitted_cap(sd_bus_creds *c, int capability) {
         assert_return(c, -EINVAL);
         assert_return(capability >= 0, -EINVAL);
@@ -626,6 +745,7 @@ _public_ int sd_bus_creds_has_bounding_cap(sd_bus_creds *c, int capability) {
 
         return has_cap(c, CAP_OFFSET_BOUNDING, capability);
 }
+#endif // 0
 
 static int parse_caps(sd_bus_creds *c, unsigned offset, const char *p) {
         size_t sz, max;
@@ -681,11 +801,13 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
                 return 0;
 
         /* Try to retrieve PID from creds if it wasn't passed to us */
-        if (pid <= 0 && (c->mask & SD_BUS_CREDS_PID))
+        if (pid > 0) {
+                c->pid = pid;
+                c->mask |= SD_BUS_CREDS_PID;
+        } else if (c->mask & SD_BUS_CREDS_PID)
                 pid = c->pid;
-
-        /* Without pid we cannot do much... */
-        if (pid <= 0)
+        else
+                /* Without pid we cannot do much... */
                 return 0;
 
         /* Try to retrieve TID from creds if it wasn't passed to us */
@@ -697,9 +819,6 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
         if (missing == 0)
                 return 0;
 
-        c->pid = pid;
-        c->mask |= SD_BUS_CREDS_PID;
-
         if (tid > 0) {
                 c->tid = tid;
                 c->mask |= SD_BUS_CREDS_TID;
@@ -734,9 +853,14 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
                                         if (p) {
                                                 p += strspn(p, WHITESPACE);
 
-                                                r = parse_pid(p, &c->ppid);
-                                                if (r < 0)
-                                                        return r;
+                                                /* Explicitly check for PPID 0 (which is the case for PID 1) */
+                                                if (!streq(p, "0")) {
+                                                        r = parse_pid(p, &c->ppid);
+                                                        if (r < 0)
+                                                                return r;
+
+                                                } else
+                                                        c->ppid = 0;
 
                                                 c->mask |= SD_BUS_CREDS_PPID;
                                                 continue;
@@ -891,7 +1015,17 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
 
         if (missing & SD_BUS_CREDS_EXE) {
                 r = get_process_exe(pid, &c->exe);
-                if (r < 0) {
+                if (r == -ESRCH) {
+                        /* Unfortunately we cannot really distinguish
+                         * the case here where the process does not
+                         * exist, and /proc/$PID/exe being unreadable
+                         * because $PID is a kernel thread. Hence,
+                         * assume it is a kernel thread, and rely on
+                         * that this case is caught with a later
+                         * call. */
+                        c->exe = NULL;
+                        c->mask |= SD_BUS_CREDS_EXE;
+                } else if (r < 0) {
                         if (r != -EPERM && r != -EACCES)
                                 return r;
                 } else
@@ -903,17 +1037,16 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
 
                 p = procfs_file_alloca(pid, "cmdline");
                 r = read_full_file(p, &c->cmdline, &c->cmdline_size);
+                if (r == -ENOENT)
+                        return -ESRCH;
                 if (r < 0) {
-                        if (r == -ENOENT)
-                                return -ESRCH;
                         if (r != -EPERM && r != -EACCES)
                                 return r;
                 } else {
-                        if (c->cmdline_size == 0) {
-                                free(c->cmdline);
-                                c->cmdline = NULL;
-                        } else
-                                c->mask |= SD_BUS_CREDS_CMDLINE;
+                        if (c->cmdline_size == 0)
+                                c->cmdline = mfree(c->cmdline);
+
+                        c->mask |= SD_BUS_CREDS_CMDLINE;
                 }
         }
 
@@ -924,16 +1057,16 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
                         return -ENOMEM;
 
                 r = read_one_line_file(p, &c->tid_comm);
+                if (r == -ENOENT)
+                        return -ESRCH;
                 if (r < 0) {
-                        if (r == -ENOENT)
-                                return -ESRCH;
                         if (r != -EPERM && r != -EACCES)
                                 return r;
                 } else
                         c->mask |= SD_BUS_CREDS_TID_COMM;
         }
 
-        if (missing & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_OWNER_UID)) {
+        if (missing & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_USER_SLICE|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_OWNER_UID)) {
 
                 if (!c->cgroup) {
                         r = cg_pid_get_path(NULL, pid, &c->cgroup);
@@ -950,13 +1083,17 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
                 }
 
                 if (c->cgroup)
-                        c->mask |= missing & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_OWNER_UID);
+                        c->mask |= missing & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_USER_SLICE|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_OWNER_UID);
         }
 
         if (missing & SD_BUS_CREDS_AUDIT_SESSION_ID) {
                 r = audit_session_from_pid(pid, &c->audit_session_id);
-                if (r < 0) {
-                        if (r != -EOPNOTSUPP && r != -ENXIO && r != -ENOENT && r != -EPERM && r != -EACCES)
+                if (r == -ENODATA) {
+                        /* ENODATA means: no audit session id assigned */
+                        c->audit_session_id = AUDIT_SESSION_INVALID;
+                        c->mask |= SD_BUS_CREDS_AUDIT_SESSION_ID;
+                } else if (r < 0) {
+                        if (r != -EOPNOTSUPP && r != -ENOENT && r != -EPERM && r != -EACCES)
                                 return r;
                 } else
                         c->mask |= SD_BUS_CREDS_AUDIT_SESSION_ID;
@@ -964,20 +1101,48 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
 
         if (missing & SD_BUS_CREDS_AUDIT_LOGIN_UID) {
                 r = audit_loginuid_from_pid(pid, &c->audit_login_uid);
-                if (r < 0) {
-                        if (r != -EOPNOTSUPP && r != -ENXIO && r != -ENOENT && r != -EPERM && r != -EACCES)
+                if (r == -ENODATA) {
+                        /* ENODATA means: no audit login uid assigned */
+                        c->audit_login_uid = UID_INVALID;
+                        c->mask |= SD_BUS_CREDS_AUDIT_LOGIN_UID;
+                } else if (r < 0) {
+                        if (r != -EOPNOTSUPP && r != -ENOENT && r != -EPERM && r != -EACCES)
                                 return r;
                 } else
                         c->mask |= SD_BUS_CREDS_AUDIT_LOGIN_UID;
         }
 
+        if (missing & SD_BUS_CREDS_TTY) {
+                r = get_ctty(pid, NULL, &c->tty);
+                if (r == -ENXIO) {
+                        /* ENXIO means: process has no controlling TTY */
+                        c->tty = NULL;
+                        c->mask |= SD_BUS_CREDS_TTY;
+                } else if (r < 0) {
+                        if (r != -EPERM && r != -EACCES && r != -ENOENT)
+                                return r;
+                } else
+                        c->mask |= SD_BUS_CREDS_TTY;
+        }
+
+        /* In case only the exe path was to be read we cannot
+         * distinguish the case where the exe path was unreadable
+         * because the process was a kernel thread, or when the
+         * process didn't exist at all. Hence, let's do a final check,
+         * to be sure. */
+        if (!pid_is_alive(pid))
+                return -ESRCH;
+
+        if (tid > 0 && tid != pid && !pid_is_unwaited(tid))
+                return -ESRCH;
+
         c->augmented = missing & c->mask;
 
         return 0;
 }
 
 int bus_creds_extend_by_pid(sd_bus_creds *c, uint64_t mask, sd_bus_creds **ret) {
-        _cleanup_bus_creds_unref_ sd_bus_creds *n = NULL;
+        _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *n = NULL;
         int r;
 
         assert(c);
@@ -1053,14 +1218,22 @@ int bus_creds_extend_by_pid(sd_bus_creds *c, uint64_t mask, sd_bus_creds **ret)
         }
 
         if (c->mask & mask & SD_BUS_CREDS_SUPPLEMENTARY_GIDS) {
-                n->supplementary_gids = newdup(gid_t, c->supplementary_gids, c->n_supplementary_gids);
-                if (!n->supplementary_gids)
-                        return -ENOMEM;
-                n->n_supplementary_gids = c->n_supplementary_gids;
+                if (c->supplementary_gids) {
+                        n->supplementary_gids = newdup(gid_t, c->supplementary_gids, c->n_supplementary_gids);
+                        if (!n->supplementary_gids)
+                                return -ENOMEM;
+                        n->n_supplementary_gids = c->n_supplementary_gids;
+                } else {
+                        n->supplementary_gids = NULL;
+                        n->n_supplementary_gids = 0;
+                }
+
                 n->mask |= SD_BUS_CREDS_SUPPLEMENTARY_GIDS;
         }
 
         if (c->mask & mask & SD_BUS_CREDS_COMM) {
+                assert(c->comm);
+
                 n->comm = strdup(c->comm);
                 if (!n->comm)
                         return -ENOMEM;
@@ -1069,6 +1242,8 @@ int bus_creds_extend_by_pid(sd_bus_creds *c, uint64_t mask, sd_bus_creds **ret)
         }
 
         if (c->mask & mask & SD_BUS_CREDS_TID_COMM) {
+                assert(c->tid_comm);
+
                 n->tid_comm = strdup(c->tid_comm);
                 if (!n->tid_comm)
                         return -ENOMEM;
@@ -1077,23 +1252,34 @@ int bus_creds_extend_by_pid(sd_bus_creds *c, uint64_t mask, sd_bus_creds **ret)
         }
 
         if (c->mask & mask & SD_BUS_CREDS_EXE) {
-                n->exe = strdup(c->exe);
-                if (!n->exe)
-                        return -ENOMEM;
+                if (c->exe) {
+                        n->exe = strdup(c->exe);
+                        if (!n->exe)
+                                return -ENOMEM;
+                } else
+                        n->exe = NULL;
 
                 n->mask |= SD_BUS_CREDS_EXE;
         }
 
         if (c->mask & mask & SD_BUS_CREDS_CMDLINE) {
-                n->cmdline = memdup(c->cmdline, c->cmdline_size);
-                if (!n->cmdline)
-                        return -ENOMEM;
+                if (c->cmdline) {
+                        n->cmdline = memdup(c->cmdline, c->cmdline_size);
+                        if (!n->cmdline)
+                                return -ENOMEM;
+
+                        n->cmdline_size = c->cmdline_size;
+                } else {
+                        n->cmdline = NULL;
+                        n->cmdline_size = 0;
+                }
 
-                n->cmdline_size = c->cmdline_size;
                 n->mask |= SD_BUS_CREDS_CMDLINE;
         }
 
-        if (c->mask & mask & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_OWNER_UID)) {
+        if (c->mask & mask & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_USER_SLICE|SD_BUS_CREDS_OWNER_UID)) {
+                assert(c->cgroup);
+
                 n->cgroup = strdup(c->cgroup);
                 if (!n->cgroup)
                         return -ENOMEM;
@@ -1102,10 +1288,12 @@ int bus_creds_extend_by_pid(sd_bus_creds *c, uint64_t mask, sd_bus_creds **ret)
                 if (!n->cgroup_root)
                         return -ENOMEM;
 
-                n->mask |= mask & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_OWNER_UID);
+                n->mask |= mask & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_USER_SLICE|SD_BUS_CREDS_OWNER_UID);
         }
 
         if (c->mask & mask & (SD_BUS_CREDS_EFFECTIVE_CAPS|SD_BUS_CREDS_PERMITTED_CAPS|SD_BUS_CREDS_INHERITABLE_CAPS|SD_BUS_CREDS_BOUNDING_CAPS)) {
+                assert(c->capability);
+
                 n->capability = memdup(c->capability, DIV_ROUND_UP(cap_last_cap(), 32U) * 4 * 4);
                 if (!n->capability)
                         return -ENOMEM;
@@ -1114,6 +1302,8 @@ int bus_creds_extend_by_pid(sd_bus_creds *c, uint64_t mask, sd_bus_creds **ret)
         }
 
         if (c->mask & mask & SD_BUS_CREDS_SELINUX_CONTEXT) {
+                assert(c->label);
+
                 n->label = strdup(c->label);
                 if (!n->label)
                         return -ENOMEM;
@@ -1129,7 +1319,19 @@ int bus_creds_extend_by_pid(sd_bus_creds *c, uint64_t mask, sd_bus_creds **ret)
                 n->mask |= SD_BUS_CREDS_AUDIT_LOGIN_UID;
         }
 
+        if (c->mask & mask & SD_BUS_CREDS_TTY) {
+                if (c->tty) {
+                        n->tty = strdup(c->tty);
+                        if (!n->tty)
+                                return -ENOMEM;
+                } else
+                        n->tty = NULL;
+                n->mask |= SD_BUS_CREDS_TTY;
+        }
+
         if (c->mask & mask & SD_BUS_CREDS_UNIQUE_NAME) {
+                assert(c->unique_name);
+
                 n->unique_name = strdup(c->unique_name);
                 if (!n->unique_name)
                         return -ENOMEM;
@@ -1137,15 +1339,20 @@ int bus_creds_extend_by_pid(sd_bus_creds *c, uint64_t mask, sd_bus_creds **ret)
         }
 
         if (c->mask & mask & SD_BUS_CREDS_WELL_KNOWN_NAMES) {
-                n->well_known_names = strv_copy(c->well_known_names);
-                if (!n->well_known_names)
-                        return -ENOMEM;
+                if (strv_isempty(c->well_known_names))
+                        n->well_known_names = NULL;
+                else {
+                        n->well_known_names = strv_copy(c->well_known_names);
+                        if (!n->well_known_names)
+                                return -ENOMEM;
+                }
                 n->well_known_names_driver = c->well_known_names_driver;
                 n->well_known_names_local = c->well_known_names_local;
                 n->mask |= SD_BUS_CREDS_WELL_KNOWN_NAMES;
         }
 
         if (c->mask & mask & SD_BUS_CREDS_DESCRIPTION) {
+                assert(c->description);
                 n->description = strdup(c->description);
                 if (!n->description)
                         return -ENOMEM;