nss: block various signals while running NSS lookups

Let's make sure our poll() calls don't get interrupted where they shouldn't (SIGALRM, ...), but allow them to be
interrupted where they should (SIGINT, ...).

Fixes #1965

1 files changed, 7 insertions, 0 deletions

diff --git a/src/nss-myhostname/nss-myhostname.c b/src/nss-myhostname/nss-myhostname.c
index ee10b105ea..e438625814 100644
--- a/src/nss-myhostname/nss-myhostname.c
+++ b/src/nss-myhostname/nss-myhostname.c
@@ -31,6 +31,7 @@
 #include "local-addresses.h"
 #include "macro.h"
 #include "nss-util.h"
+#include "signal-util.h"
 #include "string-util.h"
 #include "util.h"
 
@@ -63,6 +64,8 @@ enum nss_status _nss_myhostname_gethostbyname4_r(
         char *r_name;
         unsigned n;
 
+        BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
+
         assert(name);
         assert(pat);
         assert(buffer);
@@ -327,6 +330,8 @@ enum nss_status _nss_myhostname_gethostbyname3_r(
         uint32_t local_address_ipv4 = 0;
         int n_addresses = 0;
 
+        BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
+
         assert(name);
         assert(host);
         assert(buffer);
@@ -409,6 +414,8 @@ enum nss_status _nss_myhostname_gethostbyaddr2_r(
         bool additional_from_hostname = false;
         unsigned n;
 
+        BLOCK_SIGNALS(NSS_SIGNALS_BLOCK);
+
         assert(addr);
         assert(host);
         assert(buffer);