commit a1b0a0b9cd313535f954d8033ea6672ddd5ccc2a Author: Nick Mathewson nickm@torproject.org Date: Thu Nov 30 11:44:15 2017 -0500

Avoid use-after-free error in 20020 fix

CID 1424328; found by coverity; bugfix on 93dbce4ddd98ca9a4ff2f; bug not in any released Tor. --- src/or/routerlist.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/or/routerlist.c b/src/or/routerlist.c index 24c0a4e07..ef1538279 100644 --- a/src/or/routerlist.c +++ b/src/or/routerlist.c @@ -5197,6 +5197,10 @@ update_consensus_router_descriptor_downloads(time_t now, int is_vote, log_warn(LD_BUG, "Failed to re-parse a router."); continue; } + /* need to compute this now, since add_to_routerlist may free. */ + char time_cert_expires[ISO_TIME_LEN+1]; + format_iso_time(time_cert_expires, ri->cert_expiration_time); + r = router_add_to_routerlist(ri, &msg, 1, 0); if (WRA_WAS_OUTDATED(r)) { log_warn(LD_DIR, "Couldn't add re-parsed router: %s. This isn't " @@ -5205,12 +5209,10 @@ update_consensus_router_descriptor_downloads(time_t now, int is_vote, msg?msg:"???"); if (r == ROUTER_CERTS_EXPIRED) { char time_cons[ISO_TIME_LEN+1]; - char time_cert[ISO_TIME_LEN+1]; format_iso_time(time_cons, consensus->valid_after); - format_iso_time(time_cert, ri->cert_expiration_time); log_warn(LD_DIR, " (I'm looking at a consensus from %s; This " "router's certificates began expiring at %s.)", - time_cons, time_cert); + time_cons, time_cert_expires); } } } SMARTLIST_FOREACH_END(sd);