Fix changes to interface list during getifaddrs calls.

This commit is contained in:
Ulrich Drepper 2010-04-03 20:36:59 -07:00
parent 3ed8e24122
commit b8b14c4cc3
2 changed files with 53 additions and 12 deletions

View File

@ -1,3 +1,13 @@
2010-04-03 Ulrich Drepper <drepper@redhat.com>
[BZ #11387]
* sysdeps/unix/sysv/linux/ifaddrs.c (map_newlin): Don't abort on
unknown interface, return -1.
(getifaddrs_internal): Rename from getifaddrs. Handle errors in
map_newlink be returning -EAGAIN.
(getifaddrs): If -EAGAIN is returned from getifaddrs_internal try
again.
2010-03-25 Ryan S. Arnold <rsa@us.ibm.com>
* sysdeps/unix/sysv/linux/getsysstats.c (next_line): Remove

View File

@ -1,5 +1,5 @@
/* getifaddrs -- get names and addresses of all network interfaces
Copyright (C) 2003-2008, 2009 Free Software Foundation, Inc.
Copyright (C) 2003-2008, 2009, 2010 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@ -315,17 +315,19 @@ map_newlink (int index, struct ifaddrs_storage *ifas, int *map, int max)
else if (map[i] == index)
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;
@ -481,6 +483,13 @@ 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))
@ -565,9 +574,11 @@ 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;
@ -747,9 +758,13 @@ 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
@ -826,6 +841,22 @@ 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)