diff options
| -rw-r--r-- | libc/inet/ifaddrs.c | 53 |
1 files changed, 42 insertions, 11 deletions
diff --git a/libc/inet/ifaddrs.c b/libc/inet/ifaddrs.c index 0c9310651..72771d35a 100644 --- a/libc/inet/ifaddrs.c +++ b/libc/inet/ifaddrs.c @@ -339,17 +339,19 @@ map_newlink (int idx, struct ifaddrs_storage *ifas, int *map, int max) else if (map[i] == idx) return i; } - /* This should never be reached. If this will be reached, we have - a very big problem. */ - abort (); + + /* This means interfaces changed inbetween the reading of the + RTM_GETLINK and RTM_GETADDR information. We have to repeat + everything. */ + return -1; } /* Create a linked list of `struct ifaddrs' structures, one for each network interface on the host machine. If successful, store the list in *IFAP and return 0. On errors, return -1 and set `errno'. */ -int -getifaddrs (struct ifaddrs **ifap) +static int +getifaddrs_internal (struct ifaddrs **ifap) { struct netlink_handle nh = { 0, 0, 0, NULL, NULL }; struct netlink_res *nlp; @@ -496,6 +498,13 @@ getifaddrs (struct ifaddrs **ifap) kernel. */ ifa_index = map_newlink (ifim->ifi_index - 1, ifas, map_newlink_data, newlink); + if (__builtin_expect (ifa_index == -1, 0)) + { + try_again: + result = -EAGAIN; + free (ifas); + goto exit_free; + } ifas[ifa_index].ifa.ifa_flags = ifim->ifi_flags; while (RTA_OK (rta, rtasize)) @@ -580,9 +589,11 @@ getifaddrs (struct ifaddrs **ifap) 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_data, newlink)].ifa.ifa_flags; + int idx = map_newlink (ifam->ifa_index - 1, ifas, + map_newlink_data, newlink); + if (__builtin_expect (idx == -1, 0)) + goto try_again; + ifas[ifa_index].ifa.ifa_flags = ifas[idx].ifa.ifa_flags; if (ifa_index > 0) ifas[ifa_index - 1].ifa.ifa_next = &ifas[ifa_index].ifa; ++newaddr_idx; @@ -768,9 +779,13 @@ getifaddrs (struct ifaddrs **ifap) /* If we didn't get the interface name with the 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_data, newlink)].ifa.ifa_name; + { + int idx = map_newlink (ifam->ifa_index - 1, ifas, + map_newlink_data, newlink); + if (__builtin_expect (idx == -1, 0)) + goto try_again; + ifas[ifa_index].ifa.ifa_name = ifas[idx].ifa.ifa_name; + } /* Calculate the netmask. */ if (ifas[ifa_index].ifa.ifa_addr @@ -850,6 +865,22 @@ getifaddrs (struct ifaddrs **ifap) return result; } + + +/* Create a linked list of `struct ifaddrs' structures, one for each + network interface on the host machine. If successful, store the + list in *IFAP and return 0. On errors, return -1 and set `errno'. */ +int +getifaddrs (struct ifaddrs **ifap) +{ + int res; + + do + res = getifaddrs_internal (ifap); + while (res == -EAGAIN); + + return res; +} libc_hidden_def(getifaddrs) void |