On Wed, Sep 20, 2017 at 12:08:59PM +0100, Daniel P. Berrange wrote:
The commandhelper binary is a helper for commandtest that validates what file handles were inherited. For this to work reliably we must not have any libraries that leak file descriptors into commandhelper. Unfortunately some versions of gnutls will intentionally open file handles at library load time via a constructor function.
We previously hacked around this in
commit 4cbc15d037e1cd8abf5c4aa6acc30d83ae13e34d Author: Martin Kletzander <mkletzan@redhat.com> Date: Fri May 2 09:55:52 2014 +0200
tests: don't fail with newer gnutls
gnutls-3.3.0 and newer leaves 2 FDs open in order to be backwards compatible when it comes to chrooted binaries [1]. Linking commandhelper with gnutls then leaves these two FDs open and commandtest fails thanks to that. This patch does not link commandhelper with libvirt.la, but rather only the utilities making the test pass.
Based on suggestion from Daniel [2].
[1] http://lists.gnutls.org/pipermail/gnutls-help/2014-April/003429.html [2] https://www.redhat.com/archives/libvir-list/2014-April/msg01119.html
That fix relied on fact that while libvirt.so linked with gnutls, libvirt_util.la did not link to it. With the introduction of the util/vircrypto.c file that assumption is no longer valid. We must not link to libvirt_util.la at all - only gnulib and libc can (hopefully) be relied on not to open random file descriptors in constructors.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com> ---
BTW, technically a build breaker fix for the CI problems that are fallout from my previous CI build breaker fix. Leaving this for review before pushing since it is a somewhat larger fix.
cfg.mk | 8 ++++---- tests/Makefile.am | 6 ++++-- tests/commandhelper.c | 29 +++++++++++++---------------- 3 files changed, 21 insertions(+), 22 deletions(-)
diff --git a/cfg.mk b/cfg.mk index 56cb14b..f2a053f 100644 --- a/cfg.mk +++ b/cfg.mk @@ -1111,7 +1111,7 @@ $(srcdir)/src/admin/admin_client.h: $(srcdir)/src/admin/admin_protocol.x exclude_file_name_regexp--sc_avoid_strcase = ^tools/vsh\.h$$
_src1=libvirt-stream|qemu/qemu_monitor|util/vir(command|file|fdstream)|xen/xend_internal|rpc/virnetsocket|lxc/lxc_controller|locking/lock_daemon|logging/log_daemon -_test1=shunloadtest|virnettlscontexttest|virnettlssessiontest|vircgroupmock +_test1=shunloadtest|virnettlscontexttest|virnettlssessiontest|vircgroupmock|commandhelper exclude_file_name_regexp--sc_avoid_write = \ ^(src/($(_src1))|daemon/libvirtd|tools/virsh-console|tests/($(_test1)))\.c$$
@@ -1146,10 +1146,10 @@ exclude_file_name_regexp--sc_prohibit_asprintf = \ ^(cfg\.mk|bootstrap.conf$$|examples/|src/util/virstring\.[ch]$$|tests/vircgroupmock\.c$$)
exclude_file_name_regexp--sc_prohibit_strdup = \ - ^(docs/|examples/|src/util/virstring\.c|tests/vir(netserverclient|cgroup)mock.c$$) + ^(docs/|examples/|src/util/virstring\.c|tests/vir(netserverclient|cgroup)mock.c|tests/commandhelper\.c$$)
exclude_file_name_regexp--sc_prohibit_close = \ - (\.p[yl]$$|\.spec\.in$$|^docs/|^(src/util/virfile\.c|src/libvirt-stream\.c|tests/vir.+mock\.c)$$) + (\.p[yl]$$|\.spec\.in$$|^docs/|^(src/util/virfile\.c|src/libvirt-stream\.c|tests/vir.+mock\.c|tests/commandhelper\.c)$$)
exclude_file_name_regexp--sc_prohibit_empty_lines_at_EOF = \ (^tests/(qemuhelp|virhostcpu|virpcitest)data/|docs/js/.*\.js|docs/fonts/.*\.woff|\.diff|tests/virconfdata/no-newline\.conf$$) @@ -1173,7 +1173,7 @@ exclude_file_name_regexp--sc_prohibit_select = \ ^cfg\.mk$$
exclude_file_name_regexp--sc_prohibit_raw_allocation = \ - ^(docs/hacking\.html\.in|src/util/viralloc\.[ch]|examples/.*|tests/(securityselinuxhelper|(vircgroup|nss)mock)\.c|tools/wireshark/src/packet-libvirt\.c)$$ + ^(docs/hacking\.html\.in|src/util/viralloc\.[ch]|examples/.*|tests/(securityselinuxhelper|(vircgroup|nss)mock|commandhelper)\.c|tools/wireshark/src/packet-libvirt\.c)$$
exclude_file_name_regexp--sc_prohibit_readlink = \ ^src/(util/virutil|lxc/lxc_container)\.c$$ diff --git a/tests/Makefile.am b/tests/Makefile.am index 8138885..0b2305d 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -946,12 +946,14 @@ commandtest_SOURCES = \ commandtest.c testutils.h testutils.c commandtest_LDADD = $(LDADDS)
+# Must not link to any libvirt modules - libc / gnulib only +# otherwise external libraries might unexpectedly leak +# file descriptors into commandhelper invalidating the +# test logic assumptions commandhelper_SOURCES = \ commandhelper.c commandhelper_LDADD = \ $(NO_INDIRECT_LDFLAGS) \ - $(PROBES_O) \ - ../src/libvirt_util.la \ $(GNULIB_LIBS)
commandhelper_LDFLAGS = -static diff --git a/tests/commandhelper.c b/tests/commandhelper.c index 015efda..e9e6353 100644 --- a/tests/commandhelper.c +++ b/tests/commandhelper.c @@ -28,11 +28,6 @@ #include <sys/stat.h>
#include "internal.h" -#include "virutil.h" -#include "viralloc.h" -#include "virfile.h" -#include "testutils.h" -#include "virstring.h"
#ifndef WIN32
@@ -50,11 +45,13 @@ static int envsort(const void *a, const void *b) char *bkey; int ret;
- ignore_value(VIR_STRNDUP_QUIET(akey, astr, aeq - astr)); - ignore_value(VIR_STRNDUP_QUIET(bkey, bstr, beq - bstr)); + if (!(akey = strndup(astr, aeq - astr))) + abort(); + if (!(bkey = strndup(bstr, beq - bstr))) + abort(); ret = strcmp(akey, bkey); - VIR_FREE(akey); - VIR_FREE(bkey); + free(akey); + free(bkey); return ret; }
@@ -80,8 +77,8 @@ int main(int argc, char **argv) { origenv++; }
- if (VIR_ALLOC_N_QUIET(newenv, n) < 0) - goto cleanup; + if (!(newenv = malloc(sizeof(*newenv) * n))) + abort();
origenv = environ; n = i = 0; @@ -120,7 +117,7 @@ int main(int argc, char **argv) { STREQ(cwd + strlen(cwd) - strlen("/commanddata"), "/commanddata")) strcpy(cwd, ".../commanddata"); fprintf(log, "CWD:%s\n", cwd); - VIR_FREE(cwd); + free(cwd);
fprintf(log, "UMASK:%04o\n", umask(0));
@@ -144,9 +141,9 @@ int main(int argc, char **argv) { goto cleanup; if (got == 0) break; - if (safewrite(STDOUT_FILENO, buf, got) != got) + if (write(STDOUT_FILENO, buf, got) != got) goto cleanup; - if (safewrite(STDERR_FILENO, buf, got) != got) + if (write(STDERR_FILENO, buf, got) != got) goto cleanup; }
@@ -158,8 +155,8 @@ int main(int argc, char **argv) { ret = EXIT_SUCCESS;
cleanup: - VIR_FORCE_FCLOSE(log); - VIR_FREE(newenv); + fclose(log); + free(newenv); return ret; }
-- 2.5.5
Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|