sd-bus: don't blindly take incomplete ucred bits from AF_UNIX when constructing message

[elogind.git] / src / libsystemd / sd-bus / bus-message.c

diff --git a/src/libsystemd/sd-bus/bus-message.c b/src/libsystemd/sd-bus/bus-message.c
index 1362a60f0869cb49a6f0fa16166a12b792f73571..6889754a965f15da17261c94667fc296150c5da2 100644 (file)
--- a/src/libsystemd/sd-bus/bus-message.c
+++ b/src/libsystemd/sd-bus/bus-message.c
@@ -28,7 +28,7 @@
 #include "strv.h"
 #include "time-util.h"
 #include "cgroup-util.h"
-#include "memfd.h"
+#include "memfd-util.h"
 
 #include "sd-bus.h"
 #include "bus-message.h"
@@ -148,6 +148,11 @@ static void message_free(sd_bus_message *m) {
         if (m->iovec != m->iovec_fixed)
                 free(m->iovec);
 
+        if (m->destination_ptr) {
+                free(m->destination_ptr);
+                m->destination_ptr = NULL;
+        }
+
         message_reset_containers(m);
         free(m->root_container.signature);
         free(m->root_container.offsets);
@@ -415,10 +420,20 @@ int bus_message_from_header(
         m->n_fds = n_fds;
 
         if (ucred) {
-                m->creds.uid = ucred->uid;
                 m->creds.pid = ucred->pid;
+                m->creds.uid = ucred->uid;
                 m->creds.gid = ucred->gid;
-                m->creds.mask |= SD_BUS_CREDS_UID | SD_BUS_CREDS_PID | SD_BUS_CREDS_GID;
+
+                /* Due to namespace translations some data might be
+                 * missing from this ucred record. */
+                if (m->creds.pid > 0)
+                        m->creds.mask |= SD_BUS_CREDS_PID;
+
+                if (m->creds.uid != (uid_t) -1)
+                        m->creds.mask |= SD_BUS_CREDS_UID;
+
+                if (m->creds.gid != (gid_t) -1)
+                        m->creds.mask |= SD_BUS_CREDS_GID;
         }
 
         if (label) {
@@ -1097,10 +1112,10 @@ static int part_make_space(
                         uint64_t new_allocated;
 
                         new_allocated = PAGE_ALIGN(sz > 0 ? 2 * sz : 1);
-                        r = ftruncate(part->memfd, new_allocated);
+                        r = memfd_set_size(part->memfd, new_allocated);
                         if (r < 0) {
                                 m->poisoned = true;
-                                return -errno;
+                                return r;
                         }
 
                         part->allocated = new_allocated;
@@ -2820,11 +2835,12 @@ int bus_message_seal(sd_bus_message *m, uint64_t cookie, usec_t timeout) {
 
                                 /* Then, sync up real memfd size */
                                 sz = part->size;
-                                if (ftruncate(part->memfd, sz) < 0)
-                                        return -errno;
+                                r = memfd_set_size(part->memfd, sz);
+                                if (r < 0)
+                                        return r;
 
                                 /* Finally, try to seal */
-                                if (fcntl(part->memfd, F_ADD_SEALS, F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_WRITE) >= 0)
+                                if (memfd_set_sealed(part->memfd) >= 0)
                                         part->sealed = true;
                         }
         }
@@ -5374,6 +5390,12 @@ _public_ const char* sd_bus_message_get_signature(sd_bus_message *m, int complet
         return strempty(c->signature);
 }
 
+_public_ int sd_bus_message_is_empty(sd_bus_message *m) {
+        assert_return(m, -EINVAL);
+
+        return isempty(m->root_container.signature);
+}
+
 _public_ int sd_bus_message_copy(sd_bus_message *m, sd_bus_message *source, int all) {
         bool done_something = false;
         int r;