On Sun, Aug 02, 2009 at 12:15:47PM +0200, Chris Lalancette wrote: > Daniel P. Berrange wrote: > > On Fri, Jul 31, 2009 at 03:20:09PM +0200, Chris Lalancette wrote: > >> Fix a possible latent bug in qemudOpenMonitorUnix(). If the pathname > >> to the monitor is very long (i.e. >= UNIX_MAX_PATH), then strncpy will > >> *not* place a final \0 on the string (see "man strncpy"). > >> NULL terminate the buffer to ensure we don't run off the end. > >> > >> Signed-off-by: Chris Lalancette <clalance@xxxxxxxxxx> > >> --- > >> src/qemu_driver.c | 1 + > >> 1 files changed, 1 insertions(+), 0 deletions(-) > >> > >> diff --git a/src/qemu_driver.c b/src/qemu_driver.c > >> index 9fcc07a..4f173b7 100644 > >> --- a/src/qemu_driver.c > >> +++ b/src/qemu_driver.c > >> @@ -910,6 +910,7 @@ qemudOpenMonitorUnix(virConnectPtr conn, > >> memset(&addr, 0, sizeof(addr)); > >> addr.sun_family = AF_UNIX; > >> strncpy(addr.sun_path, monitor, sizeof(addr.sun_path)); > >> + NUL_TERMINATE(addr.sun_path); > >> > >> do { > >> ret = connect(monfd, (struct sockaddr *) &addr, sizeof(addr)); > > > > ACK, but this mistake is made in pretty much every use of unix > > domain sockets :-( Could you fix the others here too. > > > > > > Clearly strncpy() is just unfit for purpose, and we should plan to banish > > it in favour of a virStrncpy impl that guarnetees to add the trailing \0. > > Yeah, true. Despite the ACKs from you and markmc, I decided not to commit this > yet. It's quite a theoretical bug (you'd have to have > /var/very/long/non-standard/paths/to/libvirt), so I don't think it's absolutely > critical right now. I'll convert the rest of the users, and possible come up > with a make syntax-check rule to prevent against future use. Agreed, thanks ! Let's see with Dan if we can cook up a really clean solution, thanks ! Daniel -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ daniel@xxxxxxxxxxxx | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/ -- Libvir-list mailing list Libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list