From 31dfab9e1775a673b18858af13794c50477ac76a Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Thu, 17 Apr 2003 01:08:57 +0000 Subject: Update. * sysdeps/unix/sysv/linux/ifaddrs.c (getifaddrs): Check lengths before copying. This might leave holes in the list. Adjust pointers if necessary. (netlink_receive): Allocate only one block. (free_netlink_handle): Adjust appropriately. (getifaddrs): Lots of cleanups. --- ChangeLog | 7 ++ sysdeps/unix/sysv/linux/ifaddrs.c | 175 ++++++++++++++++++++++++-------------- 2 files changed, 118 insertions(+), 64 deletions(-) diff --git a/ChangeLog b/ChangeLog index 81dfa78503..f211511ee2 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,12 @@ 2003-04-16 Ulrich Drepper + * sysdeps/unix/sysv/linux/ifaddrs.c (getifaddrs): Check lengths + before copying. This might leave holes in the list. Adjust + pointers if necessary. + (netlink_receive): Allocate only one block. + (free_netlink_handle): Adjust appropriately. + (getifaddrs): Lots of cleanups. + * string/test-strncpy.c (do_one_test): Mark start and stop as possibly unused. diff --git a/sysdeps/unix/sysv/linux/ifaddrs.c b/sysdeps/unix/sysv/linux/ifaddrs.c index 23a61c5662..b310043b6a 100644 --- a/sysdeps/unix/sysv/linux/ifaddrs.c +++ b/sysdeps/unix/sysv/linux/ifaddrs.c @@ -252,7 +252,8 @@ netlink_open (struct netlink_handle *h) Since we get at first all RTM_NEWLINK entries, it can never happen that a RTM_NEWADDR index is not known to this map. */ static int -map_newlink (int index, int *map, int max) +internal_function +map_newlink (int index, struct ifaddrs_storage *ifas, int *map, int max) { int i; @@ -261,6 +262,8 @@ map_newlink (int index, int *map, int max) if (map[i] == -1) { map[i] = index; + if (i > 0) + ifas[i - 1].ifa.ifa_next = &ifas[i].ifa; return i; } else if (map[i] == index) @@ -389,9 +392,6 @@ getifaddrs (struct ifaddrs **ifap) if ((newlink + newaddr) == 0) goto exit_free; - /* Table for mapping kernel index to entry in our list. */ - map_newlink_data = alloca (newlink * sizeof (int)); - /* Allocate memory for all entries we have and initialize next pointer. */ ifas = (struct ifaddrs_storage *) calloc (1, @@ -404,11 +404,10 @@ getifaddrs (struct ifaddrs **ifap) goto exit_free; } - for (i = 0; i < newlink + newaddr - 1; i++) - { - ifas[i].ifa.ifa_next = &ifas[i + 1].ifa; - map_newlink_data[i] = -1; - } + /* Table for mapping kernel index to entry in our list. */ + map_newlink_data = alloca (newlink * sizeof (int)); + memset (map_newlink_data, '\xff', newlink * sizeof (int)); + ifa_data_ptr = (char *) &ifas[newlink + newaddr]; newaddr_idx = 0; /* Counter for newaddr index. */ @@ -447,7 +446,7 @@ getifaddrs (struct ifaddrs **ifap) /* Interfaces are stored in the first "newlink" entries of our list, starting in the order as we got from the kernel. */ - ifa_index = map_newlink (ifim->ifi_index - 1, + ifa_index = map_newlink (ifim->ifi_index - 1, ifas, map_newlink_data, newlink); ifas[ifa_index].ifa.ifa_flags = ifim->ifi_flags; @@ -459,36 +458,44 @@ getifaddrs (struct ifaddrs **ifap) switch (rta->rta_type) { case IFLA_ADDRESS: - ifas[ifa_index].addr.sl.sll_family = AF_PACKET; - memcpy (ifas[ifa_index].addr.sl.sll_addr, - (char *) rta_data, rta_payload); - ifas[ifa_index].addr.sl.sll_halen = rta_payload; - ifas[ifa_index].addr.sl.sll_ifindex = ifim->ifi_index; - ifas[ifa_index].addr.sl.sll_hatype = ifim->ifi_type; - - ifas[ifa_index].ifa.ifa_addr = &ifas[ifa_index].addr.sa; + if (rta_payload <= sizeof (ifas[ifa_index].addr)) + { + ifas[ifa_index].addr.sl.sll_family = AF_PACKET; + memcpy (ifas[ifa_index].addr.sl.sll_addr, + (char *) rta_data, rta_payload); + ifas[ifa_index].addr.sl.sll_halen = rta_payload; + ifas[ifa_index].addr.sl.sll_ifindex + = ifim->ifi_index; + ifas[ifa_index].addr.sl.sll_hatype = ifim->ifi_type; + + ifas[ifa_index].ifa.ifa_addr + = &ifas[ifa_index].addr.sa; + } break; case IFLA_BROADCAST: - ifas[ifa_index].broadaddr.sl.sll_family = AF_PACKET; - memcpy (ifas[ifa_index].broadaddr.sl.sll_addr, - (char *) rta_data, rta_payload); - ifas[ifa_index].broadaddr.sl.sll_halen = rta_payload; - ifas[ifa_index].broadaddr.sl.sll_ifindex - = ifim->ifi_index; - ifas[ifa_index].broadaddr.sl.sll_hatype = ifim->ifi_type; + if (rta_payload <= sizeof (ifas[ifa_index].broadaddr)) + { + ifas[ifa_index].broadaddr.sl.sll_family = AF_PACKET; + memcpy (ifas[ifa_index].broadaddr.sl.sll_addr, + (char *) rta_data, rta_payload); + ifas[ifa_index].broadaddr.sl.sll_halen = rta_payload; + ifas[ifa_index].broadaddr.sl.sll_ifindex + = ifim->ifi_index; + ifas[ifa_index].broadaddr.sl.sll_hatype + = ifim->ifi_type; - ifas[ifa_index].ifa.ifa_broadaddr - = &ifas[ifa_index].broadaddr.sa; + ifas[ifa_index].ifa.ifa_broadaddr + = &ifas[ifa_index].broadaddr.sa; + } break; case IFLA_IFNAME: /* Name of Interface */ if ((rta_payload + 1) <= sizeof (ifas[ifa_index].name)) { ifas[ifa_index].ifa.ifa_name = ifas[ifa_index].name; - strncpy (ifas[ifa_index].name, rta_data, - rta_payload); - ifas[ifa_index].name[rta_payload] = '\0'; + *(char *) __mempcpy (ifas[ifa_index].name, rta_data, + rta_payload) = '\0'; } break; @@ -521,13 +528,15 @@ getifaddrs (struct ifaddrs **ifap) size_t rtasize = IFA_PAYLOAD (nlh); /* New Addresses are stored in the order we got them from - the kernel after interfaces. Theoretically it is possible + the kernel after the interfaces. Theoretically it is possible that we have holes in the interface part of the list, but we always have already the interface for this address. */ ifa_index = newlink + newaddr_idx; ifas[ifa_index].ifa.ifa_flags - = ifas[map_newlink (ifam->ifa_index - 1, + = ifas[map_newlink (ifam->ifa_index - 1, ifas, map_newlink_data, newlink)].ifa.ifa_flags; + if (ifa_index > 0) + ifas[ifa_index - 1].ifa.ifa_next = &ifas[ifa_index].ifa; ++newaddr_idx; while (RTA_OK (rta, rtasize)) @@ -565,21 +574,28 @@ getifaddrs (struct ifaddrs **ifap) switch (ifam->ifa_family) { case AF_INET: - memcpy (&((struct sockaddr_in *) sa)->sin_addr, - rta_data, rta_payload); + /* Size must match that of an address for IPv4. */ + if (rta_payload == 4) + memcpy (&((struct sockaddr_in *) sa)->sin_addr, + rta_data, rta_payload); break; case AF_INET6: - memcpy (&((struct sockaddr_in6 *) sa)->sin6_addr, - rta_data, rta_payload); - if (IN6_IS_ADDR_LINKLOCAL (rta_data) || - IN6_IS_ADDR_MC_LINKLOCAL (rta_data)) - ((struct sockaddr_in6 *) sa)->sin6_scope_id = - ifam->ifa_scope; + /* Size must match that of an address for IPv6. */ + if (rta_payload == 16) + { + memcpy (&((struct sockaddr_in6 *) sa)->sin6_addr, + rta_data, rta_payload); + if (IN6_IS_ADDR_LINKLOCAL (rta_data) + || IN6_IS_ADDR_MC_LINKLOCAL (rta_data)) + ((struct sockaddr_in6 *) sa)->sin6_scope_id + = ifam->ifa_scope; + } break; default: - memcpy (sa->sa_data, rta_data, rta_payload); + if (rta_payload <= sizeof (ifas[ifa_index].addr)) + memcpy (sa->sa_data, rta_data, rta_payload); break; } } @@ -605,22 +621,29 @@ getifaddrs (struct ifaddrs **ifap) switch (ifam->ifa_family) { case AF_INET: - memcpy (&ifas[ifa_index].addr.s4.sin_addr, + /* Size must match that of an address for IPv4. */ + if (rta_payload == 4) + memcpy (&ifas[ifa_index].addr.s4.sin_addr, rta_data, rta_payload); break; case AF_INET6: - memcpy (&ifas[ifa_index].addr.s6.sin6_addr, - rta_data, rta_payload); - if (IN6_IS_ADDR_LINKLOCAL (rta_data) || - IN6_IS_ADDR_MC_LINKLOCAL (rta_data)) - ifas[ifa_index].addr.s6.sin6_scope_id = - ifam->ifa_scope; + /* Size must match that of an address for IPv6. */ + if (rta_payload == 16) + { + memcpy (&ifas[ifa_index].addr.s6.sin6_addr, + rta_data, rta_payload); + if (IN6_IS_ADDR_LINKLOCAL (rta_data) || + IN6_IS_ADDR_MC_LINKLOCAL (rta_data)) + ifas[ifa_index].addr.s6.sin6_scope_id = + ifam->ifa_scope; + } break; default: - memcpy (ifas[ifa_index].addr.sa.sa_data, - rta_data, rta_payload); + if (rta_payload <= sizeof (ifas[ifa_index].addr)) + memcpy (ifas[ifa_index].addr.sa.sa_data, + rta_data, rta_payload); break; } break; @@ -639,22 +662,29 @@ getifaddrs (struct ifaddrs **ifap) switch (ifam->ifa_family) { case AF_INET: - memcpy (&ifas[ifa_index].broadaddr.s4.sin_addr, - rta_data, rta_payload); + /* Size must match that of an address for IPv4. */ + if (rta_payload == 4) + memcpy (&ifas[ifa_index].broadaddr.s4.sin_addr, + rta_data, rta_payload); break; case AF_INET6: - memcpy (&ifas[ifa_index].broadaddr.s6.sin6_addr, - rta_data, rta_payload); - if (IN6_IS_ADDR_LINKLOCAL (rta_data) - || IN6_IS_ADDR_MC_LINKLOCAL (rta_data)) - ifas[ifa_index].broadaddr.s6.sin6_scope_id - = ifam->ifa_scope; + /* Size must match that of an address for IPv6. */ + if (rta_payload == 16) + { + memcpy (&ifas[ifa_index].broadaddr.s6.sin6_addr, + rta_data, rta_payload); + if (IN6_IS_ADDR_LINKLOCAL (rta_data) + || IN6_IS_ADDR_MC_LINKLOCAL (rta_data)) + ifas[ifa_index].broadaddr.s6.sin6_scope_id + = ifam->ifa_scope; + } break; default: - memcpy (&ifas[ifa_index].broadaddr.sa.sa_data, - rta_data, rta_payload); + if (rta_payload <= sizeof (ifas[ifa_index].addr)) + memcpy (&ifas[ifa_index].broadaddr.sa.sa_data, + rta_data, rta_payload); break; } break; @@ -663,9 +693,8 @@ getifaddrs (struct ifaddrs **ifap) if (rta_payload + 1 <= sizeof (ifas[ifa_index].name)) { ifas[ifa_index].ifa.ifa_name = ifas[ifa_index].name; - strncpy (ifas[ifa_index].name, rta_data, - rta_payload); - ifas[ifa_index].name[rta_payload] = '\0'; + *(char *) __mempcpy (ifas[ifa_index].name, rta_data, + rta_payload) = '\0'; } else abort (); @@ -686,7 +715,7 @@ getifaddrs (struct ifaddrs **ifap) address, use the name from the interface entry. */ if (ifas[ifa_index].ifa.ifa_name == NULL) ifas[ifa_index].ifa.ifa_name - = ifas[map_newlink (ifam->ifa_index - 1, + = ifas[map_newlink (ifam->ifa_index - 1, ifas, map_newlink_data, newlink)].ifa.ifa_name; /* Calculate the netmask. */ @@ -738,6 +767,24 @@ getifaddrs (struct ifaddrs **ifap) } } + assert (ifa_data_ptr <= (char *) &ifas[newlink + newaddr] + ifa_data_size); + + if (newaddr_idx > 0) + { + for (i = 0; i < newlink; ++i) + if (map_newlink_data[i] == -1) + { + /* We have fewer links then we anticipated. Adjust the + forward pointer to the first address entry. */ + ifas[i - 1].ifa.ifa_next = &ifas[newlink].ifa; + } + + if (i == 0 && newlink > 0) + /* No valid link, but we allocated memory. We have to + populate the first entry. */ + memmove (ifas, &ifas[newlink], sizeof (struct ifaddrs_storage)); + } + if (ifap != NULL) *ifap = &ifas[0].ifa; -- cgit 1.4.1