dhcp: fix creation of req_opts array

GREEDY_REALLOC needs to have two size variables: one for the
allocated size, and a second one for the used size. Using
the allocated size only lead to leaving some elements unitialized
and assigning some more than once.

diff --git a/src/libsystemd-dhcp/dhcp-client.c b/src/libsystemd-dhcp/dhcp-client.c
index 9f7a826211d2a3b79fa54f3a4690f77e0b7ffd15..b9492a5a680d349781f2c3e4b03b2dfd850e6830 100644 (file)
--- a/src/libsystemd-dhcp/dhcp-client.c
+++ b/src/libsystemd-dhcp/dhcp-client.c
@@ -54,6 +54,7 @@ struct sd_dhcp_client {
         union sockaddr_union link;
         sd_event_source *receive_message;
         uint8_t *req_opts;
+        size_t req_opts_allocated;
         size_t req_opts_size;
         be32_t last_addr;
         struct ether_addr mac_addr;
@@ -115,11 +116,11 @@ int sd_dhcp_client_set_request_option(sd_dhcp_client *client, uint8_t option)
                 if (client->req_opts[i] == option)
                         return -EEXIST;
 
-        if (!GREEDY_REALLOC(client->req_opts, client->req_opts_size,
+        if (!GREEDY_REALLOC(client->req_opts, client->req_opts_allocated,
                             client->req_opts_size + 1))
                 return -ENOMEM;
 
-        client->req_opts[client->req_opts_size - 1] = option;
+        client->req_opts[client->req_opts_size++] = option;
 
         return 0;
 }

diff --git a/src/libsystemd-dhcp/test-dhcp-client.c b/src/libsystemd-dhcp/test-dhcp-client.c
index 617236b5df6c38ff23c86dd21ad7f1827775845d..929b869ec331dd853ffd1530c77595d1ef4db7df 100644 (file)
--- a/src/libsystemd-dhcp/test-dhcp-client.c
+++ b/src/libsystemd-dhcp/test-dhcp-client.c
@@ -85,6 +85,7 @@ static void test_request_basic(sd_event *e)
         assert(sd_dhcp_client_set_request_option(client, 33) == 0);
         assert(sd_dhcp_client_set_request_option(client, 33) == -EEXIST);
         assert(sd_dhcp_client_set_request_option(client, 44) == 0);
+        assert(sd_dhcp_client_set_request_option(client, 33) == -EEXIST);
 }
 
 static uint16_t client_checksum(void *buf, int len)