From: Daniel P. Berrangé <berrange@redhat.com> Although the network XML parser should already be rejecting hostnames with forbidden characters, add sanity checking before writing the dnsmasq hostsfile / addhosts files that no unexpected whitespace is present. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> --- src/util/virdnsmasq.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/src/util/virdnsmasq.c b/src/util/virdnsmasq.c index 0e12e9ab38..a66577fd67 100644 --- a/src/util/virdnsmasq.c +++ b/src/util/virdnsmasq.c @@ -198,6 +198,19 @@ addnhostsWrite(int fd, static int addnhostsSave(dnsmasqAddnHostsfile *addnhostsfile) { + size_t i, j; + for (i = 0; i < addnhostsfile->nhosts; i++) { + for (j = 0; j < addnhostsfile->hosts[i].nhostnames; j++) { + if (strcspn(addnhostsfile->hosts[i].hostnames[j], "\t\n\r ") != + strlen(addnhostsfile->hosts[i].hostnames[j])) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("dnsmasq hostname '%1$s' contains forbidden whitespace"), + addnhostsfile->hosts[i].hostnames[j]); + return -1; + } + } + } + return virFileRewrite(addnhostsfile->path, 0600, -1, -1, addnhostsWrite, @@ -341,6 +354,17 @@ hostsfileWrite(int fd, static int hostsfileSave(dnsmasqHostsfile *hostsfile) { + size_t i; + for (i = 0; i < hostsfile->nhosts; i++) { + if (strcspn(hostsfile->hosts[i].host, "\t\n\r ") != + strlen(hostsfile->hosts[i].host)) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("dnsmasq hostname '%1$s' contains forbidden whitespace"), + hostsfile->hosts[i].host); + return -1; + } + } + return virFileRewrite(hostsfile->path, 0600, -1, -1, hostsfileWrite, -- 2.56.0