commit d8e24684b6607baa95dd4950a14ea671edcef1dc Author: rl1987 <rl1987@sdf.lonestar.org> Date: Wed Apr 8 18:33:18 2020 +0300 Check for possible failures of tor_inet_ntop/tor_inet_ntoa in fmt_addr32 and tor_dup_ip --- src/lib/net/address.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) diff --git a/src/lib/net/address.c b/src/lib/net/address.c index b8f5f3774..b24fe6c91 100644 --- a/src/lib/net/address.c +++ b/src/lib/net/address.c @@ -1196,14 +1196,24 @@ fmt_addrport(const tor_addr_t *addr, uint16_t port) /** Like fmt_addr(), but takes <b>addr</b> as a host-order IPv4 * addresses. Also not thread-safe, also clobbers its return buffer on - * repeated calls. */ + * repeated calls. Clean internal buffer and return empty string on failure. */ const char * fmt_addr32(uint32_t addr) { static char buf[INET_NTOA_BUF_LEN]; struct in_addr in; + int success; + in.s_addr = htonl(addr); - tor_inet_ntoa(&in, buf, sizeof(buf)); + + success = tor_inet_ntoa(&in, buf, sizeof(buf)); + tor_assertf_nonfatal(success > 0, + "Failed to convert IP %04X to string", addr); + + if (success <= 0) { + memset(buf, 0, INET_NTOA_BUF_LEN); + } + return buf; } @@ -1995,17 +2005,24 @@ parse_port_range(const char *port, uint16_t *port_min_out, } /** Given a host-order <b>addr</b>, call tor_inet_ntop() on it - * and return a strdup of the resulting address. + * and return a strdup of the resulting address. Return NULL if + * tor_inet_ntop() fails. */ char * tor_dup_ip(uint32_t addr) { + const char *ip_str; char buf[TOR_ADDR_BUF_LEN]; struct in_addr in; in.s_addr = htonl(addr); - tor_inet_ntop(AF_INET, &in, buf, sizeof(buf)); - return tor_strdup(buf); + ip_str = tor_inet_ntop(AF_INET, &in, buf, sizeof(buf)); + + tor_assertf_nonfatal(ip_str, "Failed to duplicate IP %04X", addr); + if (ip_str) + return tor_strdup(buf); + + return NULL; } /**