Re: [libvirt] [PATCH 1/5] util: simplify virSetUIDGIDWithCaps

On 03/25/2013 08:25 AM, Paolo Bonzini wrote: > The need_prctl variable is not really needed. If it is false, > capng_apply will be called twice with the same set, causing > a little extra work but no problem. This keeps the code a bit > simpler. > > It is also clearer to invoke capng_apply(CAPNG_SELECT_BOUNDS) > separately, to make sure it is done while we have CAP_SETPCAP. > > Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com&gt; > --- > src/util/virutil.c | 18 +++++++++++------- > 1 file changed, 11 insertions(+), 7 deletions(-) > /* Change to the temp capabilities */ > - if ((capng_ret = capng_apply(CAPNG_SELECT_BOTH)) < 0) { > + if ((capng_ret = capng_apply(CAPNG_SELECT_CAPS)) < 0) { Beforehand, we limited both caps and bounding set, with an overlarge set, now you are limiting just caps... > virReportError(VIR_ERR_INTERNAL_ERROR, > _("cannot apply process capabilities %d"), capng_ret); > goto cleanup; > @@ -3063,12 +3061,18 @@ virSetUIDGIDWithCaps(uid_t uid, gid_t gid, unsigned long long capBits, > goto cleanup; > > /* Tell it we are done keeping capabilities */ > - if (need_prctl && prctl(PR_SET_KEEPCAPS, 0, 0, 0, 0)) { > + if (prctl(PR_SET_KEEPCAPS, 0, 0, 0, 0)) { > virReportSystemError(errno, "%s", > _("prctl failed to reset KEEPCAPS")); > goto cleanup; > } > > + /* Set bounding set while we have CAP_SETPCAP. Unfortunately we cannot > + * do this if we failed to get the capability above, so ignore the > + * return value. > + */ > + capng_apply(CAPNG_SELECT_BOUNDS); ...and then separately limiting bounds, but still while having an overlarge set. > + > /* Drop the caps that allow setuid/gid (unless they were requested) */ > if (need_setgid) > capng_update(CAPNG_DROP, CAPNG_EFFECTIVE|CAPNG_PERMITTED, CAP_SETGID); > @@ -3078,7 +3082,7 @@ virSetUIDGIDWithCaps(uid_t uid, gid_t gid, unsigned long long capBits, > if (need_setpcap) > capng_update(CAPNG_DROP, CAPNG_EFFECTIVE|CAPNG_PERMITTED, CAP_SETPCAP); Here, the set is now pruned to size... > > - if (need_prctl && ((capng_ret = capng_apply(CAPNG_SELECT_BOTH)) < 0)) { > + if (((capng_ret = capng_apply(CAPNG_SELECT_CAPS)) < 0)) { ...but you are now only limiting caps, not the bounding set. Is that correct?

Does this need to be considered for 1.0.4, or can we delay it to post-release?