diff options
Diffstat (limited to 'iterator/iter_utils.c')
| -rw-r--r-- | iterator/iter_utils.c | 62 |
1 files changed, 51 insertions, 11 deletions
diff --git a/iterator/iter_utils.c b/iterator/iter_utils.c index 10a8ec3eb08f..f291178d2319 100644 --- a/iterator/iter_utils.c +++ b/iterator/iter_utils.c @@ -1284,8 +1284,17 @@ iter_get_next_root(struct iter_hints* hints, struct iter_forwards* fwd, uint16_t* c) { uint16_t c1 = *c, c2 = *c; - int r1 = hints_next_root(hints, &c1); - int r2 = forwards_next_root(fwd, &c2); + int r1, r2; + int nolock = 1; + + /* prelock both forwards and hints for atomic read. */ + lock_rw_rdlock(&fwd->lock); + lock_rw_rdlock(&hints->lock); + r1 = hints_next_root(hints, &c1, nolock); + r2 = forwards_next_root(fwd, &c2, nolock); + lock_rw_unlock(&fwd->lock); + lock_rw_unlock(&hints->lock); + if(!r1 && !r2) /* got none, end of list */ return 0; else if(!r1) /* got one, return that */ @@ -1450,15 +1459,21 @@ int iter_dp_cangodown(struct query_info* qinfo, struct delegpt* dp) int iter_stub_fwd_no_cache(struct module_qstate *qstate, struct query_info *qinf, - uint8_t** retdpname, size_t* retdpnamelen) + uint8_t** retdpname, size_t* retdpnamelen, uint8_t* dpname_storage, + size_t dpname_storage_len) { struct iter_hints_stub *stub; struct delegpt *dp; + int nolock = 1; /* Check for stub. */ + /* Lock both forwards and hints for atomic read. */ + lock_rw_rdlock(&qstate->env->fwds->lock); + lock_rw_rdlock(&qstate->env->hints->lock); stub = hints_lookup_stub(qstate->env->hints, qinf->qname, - qinf->qclass, NULL); - dp = forwards_lookup(qstate->env->fwds, qinf->qname, qinf->qclass); + qinf->qclass, NULL, nolock); + dp = forwards_lookup(qstate->env->fwds, qinf->qname, qinf->qclass, + nolock); /* see if forward or stub is more pertinent */ if(stub && stub->dp && dp) { @@ -1472,7 +1487,9 @@ iter_stub_fwd_no_cache(struct module_qstate *qstate, struct query_info *qinf, /* check stub */ if (stub != NULL && stub->dp != NULL) { - if(stub->dp->no_cache) { + int stub_no_cache = stub->dp->no_cache; + lock_rw_unlock(&qstate->env->fwds->lock); + if(stub_no_cache) { char qname[255+1]; char dpname[255+1]; dname_str(qinf->qname, qname); @@ -1480,15 +1497,27 @@ iter_stub_fwd_no_cache(struct module_qstate *qstate, struct query_info *qinf, verbose(VERB_ALGO, "stub for %s %s has no_cache", qname, dpname); } if(retdpname) { - *retdpname = stub->dp->name; + if(stub->dp->namelen > dpname_storage_len) { + verbose(VERB_ALGO, "no cache stub dpname too long"); + lock_rw_unlock(&qstate->env->hints->lock); + *retdpname = NULL; + *retdpnamelen = 0; + return stub_no_cache; + } + memmove(dpname_storage, stub->dp->name, + stub->dp->namelen); + *retdpname = dpname_storage; *retdpnamelen = stub->dp->namelen; } - return (stub->dp->no_cache); + lock_rw_unlock(&qstate->env->hints->lock); + return stub_no_cache; } /* Check for forward. */ if (dp) { - if(dp->no_cache) { + int dp_no_cache = dp->no_cache; + lock_rw_unlock(&qstate->env->hints->lock); + if(dp_no_cache) { char qname[255+1]; char dpname[255+1]; dname_str(qinf->qname, qname); @@ -1496,11 +1525,22 @@ iter_stub_fwd_no_cache(struct module_qstate *qstate, struct query_info *qinf, verbose(VERB_ALGO, "forward for %s %s has no_cache", qname, dpname); } if(retdpname) { - *retdpname = dp->name; + if(dp->namelen > dpname_storage_len) { + verbose(VERB_ALGO, "no cache dpname too long"); + lock_rw_unlock(&qstate->env->fwds->lock); + *retdpname = NULL; + *retdpnamelen = 0; + return dp_no_cache; + } + memmove(dpname_storage, dp->name, dp->namelen); + *retdpname = dpname_storage; *retdpnamelen = dp->namelen; } - return (dp->no_cache); + lock_rw_unlock(&qstate->env->fwds->lock); + return dp_no_cache; } + lock_rw_unlock(&qstate->env->fwds->lock); + lock_rw_unlock(&qstate->env->hints->lock); if(retdpname) { *retdpname = NULL; *retdpnamelen = 0; |