From eabddd8ca003af2788832208e9ab666f7d3e9378 Mon Sep 17 00:00:00 2001 From: Nick Mathewson Date: Wed, 5 Jan 2011 16:36:48 -0500 Subject: [PATCH] Handle a NULL return from addressmap_get_virtual_address Fix for bug 2328; bugfix on 0.1.2.1-alpha; bug found by doorss. --- changes/bug2328 | 6 +++++- src/or/connection_edge.c | 24 ++++++++++++++++++++---- 2 files changed, 25 insertions(+), 5 deletions(-) diff --git a/changes/bug2328 b/changes/bug2328 index e5ce492a82..f1a4fa89c5 100644 --- a/changes/bug2328 +++ b/changes/bug2328 @@ -1,4 +1,8 @@ o Minor bugfixes - Fix a bug where we would declare that we had run out of virtual addresses when the address space was only half-exhausted. Bugfix - on 0.1.1.19-rc. + on 0.1.2.1-alpha. + - Correctly handle the case where AutomapHostsOnResolve is set but no + virtual addresses are available. Fixes bug2328, bugfix on + 0.1.2.1-alpha. Bug found by doorss. + diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index 6c23775315..a01a6e38a1 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -1142,6 +1142,8 @@ address_is_in_virtual_range(const char *address) /** Return a newly allocated string holding an address of type * (one of RESOLVED_TYPE_{IPV4|HOSTNAME}) that has not yet been mapped, * and that is very unlikely to be the address of any real host. + * + * May return NULL if we have run out of virtual addresses. */ static char * addressmap_get_virtual_address(int type) @@ -1199,14 +1201,15 @@ addressmap_get_virtual_address(int type) * allocated string. If another address of the same type is already * mapped to new_address, try to return a copy of that address. * - * The string in new_address may be freed, or inserted into a map - * as appropriate. + * The string in new_address may be freed or inserted into a map + * as appropriate. May return NULL if are out of virtual addresses. **/ const char * addressmap_register_virtual_address(int type, char *new_address) { char **addrp; virtaddress_entry_t *vent; + int vent_needs_to_be_added = 0; tor_assert(new_address); tor_assert(addressmap); @@ -1215,7 +1218,7 @@ addressmap_register_virtual_address(int type, char *new_address) vent = strmap_get(virtaddress_reversemap, new_address); if (!vent) { vent = tor_malloc_zero(sizeof(virtaddress_entry_t)); - strmap_set(virtaddress_reversemap, new_address, vent); + vent_needs_to_be_added = 1; } addrp = (type == RESOLVED_TYPE_IPV4) ? @@ -1225,6 +1228,7 @@ addressmap_register_virtual_address(int type, char *new_address) if (ent && ent->new_address && !strcasecmp(new_address, ent->new_address)) { tor_free(new_address); + tor_assert(!vent_needs_to_be_added); return tor_strdup(*addrp); } else log_warn(LD_BUG, @@ -1236,7 +1240,14 @@ addressmap_register_virtual_address(int type, char *new_address) tor_free(*addrp); *addrp = addressmap_get_virtual_address(type); + if (!*addrp) { + tor_free(vent); + tor_free(new_address); + return NULL; + } log_info(LD_APP, "Registering map from %s to %s", *addrp, new_address); + if (vent_needs_to_be_added) + strmap_set(virtaddress_reversemap, new_address, vent); addressmap_register(*addrp, new_address, 2, ADDRMAPSRC_CONTROLLER); #if 0 @@ -1415,7 +1426,12 @@ connection_ap_handshake_rewrite_and_attach(edge_connection_t *conn, const char *new_addr; new_addr = addressmap_register_virtual_address( RESOLVED_TYPE_IPV4, tor_strdup(socks->address)); - tor_assert(new_addr); + if (! new_addr) { + log_warn(LD_APP, "Unable to automap address %s", + escaped_safe_str(socks->address)); + connection_mark_unattached_ap(conn, END_STREAM_REASON_INTERNAL); + return -1; + } log_info(LD_APP, "Automapping %s to %s", escaped_safe_str(socks->address), safe_str(new_addr)); strlcpy(socks->address, new_addr, sizeof(socks->address));