diff options
author | Lennart Poettering <lennart@poettering.net> | 2016-08-19 00:35:05 +0200 |
---|---|---|
committer | Lennart Poettering <lennart@poettering.net> | 2016-08-19 00:52:00 +0200 |
commit | 6e32c03ed87e5dfd3857013e909e48b5e61564c1 (patch) | |
tree | 1721440ab440942ec23ea100e0002a85ecb9b591 | |
parent | fd63e712b2025d235ce4bfbb512fada10e2690b5 (diff) |
nss-mymachines: avoid connecting to dbus from inside dbus-daemon
Inspired from the new logic in nss-systemd let's make sure we don't end up
deadlocking in nss-mymachines either in case dbus-daemon tries to a look up a
name and we want to connect to the bus.
This case is much simpler though, as there's no point in resolving virtual
machine UIDs by dbus-daemon as those should never be able to connect to the
host's busses.
-rw-r--r-- | src/nss-mymachines/nss-mymachines.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/src/nss-mymachines/nss-mymachines.c b/src/nss-mymachines/nss-mymachines.c index 8d57b26cbc..895f61c462 100644 --- a/src/nss-mymachines/nss-mymachines.c +++ b/src/nss-mymachines/nss-mymachines.c @@ -25,6 +25,7 @@ #include "alloc-util.h" #include "bus-common-errors.h" +#include "env-util.h" #include "hostname-util.h" #include "in-addr-util.h" #include "macro.h" @@ -434,6 +435,12 @@ enum nss_status _nss_mymachines_getpwnam_r( if (!machine_name_is_valid(machine)) goto not_found; + if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0) + /* Make sure we can't deadlock if we are invoked by dbus-daemon. This way, it won't be able to resolve + * these UIDs, but that should be unproblematic as containers should never be able to connect to a bus + * running on the host. */ + goto not_found; + r = sd_bus_open_system(&bus); if (r < 0) goto fail; @@ -514,6 +521,9 @@ enum nss_status _nss_mymachines_getpwuid_r( if (uid < HOST_UID_LIMIT) goto not_found; + if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0) + goto not_found; + r = sd_bus_open_system(&bus); if (r < 0) goto fail; @@ -605,6 +615,9 @@ enum nss_status _nss_mymachines_getgrnam_r( if (!machine_name_is_valid(machine)) goto not_found; + if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0) + goto not_found; + r = sd_bus_open_system(&bus); if (r < 0) goto fail; @@ -682,6 +695,9 @@ enum nss_status _nss_mymachines_getgrgid_r( if (gid < HOST_GID_LIMIT) goto not_found; + if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0) + goto not_found; + r = sd_bus_open_system(&bus); if (r < 0) goto fail; |