Re: [libvirt] [PATCH] virNetClientSetTLSSession: Restore original signal mask

Currently, we use pthread_sigmask(SIG_BLOCK, ...) prior to calling poll(). This is okay, as we don't want poll() to be interrupted. However, then - immediately as we fall out from the poll() - we try to restore the original sigmask - again using SIG_BLOCK. But as the man page says, SIG_BLOCK adds signals to the signal mask: SIG_BLOCK The set of blocked signals is the union of the current set and the set argument. Therefore, when restoring the original mask, we need to completely overwrite the one we set earlier and hence we should be using: SIG_SETMASK The set of blocked signals is set to the argument set. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- Notes: This is a very old bug. It's worth backporting onto all maint branches we have. src/rpc/virnetclient.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/rpc/virnetclient.c b/src/rpc/virnetclient.c index b288b74..255997b 100644 --- a/src/rpc/virnetclient.c +++ b/src/rpc/virnetclient.c @@ -792,7 +792,7 @@ int virNetClientSetTLSSession(virNetClientPtr client, if (ret < 0 && (errno == EAGAIN || errno == EINTR)) goto repoll; - ignore_value(pthread_sigmask(SIG_BLOCK, &oldmask, NULL)); + ignore_value(pthread_sigmask(SIG_SETMASK, &oldmask, NULL)); } ret = virNetTLSContextCheckCertificate(tls, client->tls); @@ -816,7 +816,7 @@ int virNetClientSetTLSSession(virNetClientPtr client, if (ret < 0 && (errno == EAGAIN || errno == EINTR)) goto repoll2; - ignore_value(pthread_sigmask(SIG_BLOCK, &oldmask, NULL)); + ignore_value(pthread_sigmask(SIG_SETMASK, &oldmask, NULL)); len = virNetTLSSessionRead(client->tls, buf, 1); if (len < 0 && errno != ENOMSG) {