summaryrefslogtreecommitdiff
path: root/net/sctp/protocol.c
diff options
context:
space:
mode:
authorJason Gunthorpe <jgunthorpe@obsidianresearch.com>2014-07-30 22:40:53 +0400
committerDavid S. Miller <davem@davemloft.net>2014-08-01 08:49:06 +0400
commit299ee123e19889d511092347f5fc14db0f10e3a6 (patch)
treef3ce40430141d39fbcc5aeaf54d3a6018fdd6842 /net/sctp/protocol.c
parent536721b1cb3fb50034bf6f6c7a7ea16166970e69 (diff)
downloadlinux-299ee123e19889d511092347f5fc14db0f10e3a6.tar.xz
sctp: Fixup v4mapped behaviour to comply with Sock API
The SCTP socket extensions API document describes the v4mapping option as follows: 8.1.15. Set/Clear IPv4 Mapped Addresses (SCTP_I_WANT_MAPPED_V4_ADDR) This socket option is a Boolean flag which turns on or off the mapping of IPv4 addresses. If this option is turned on, then IPv4 addresses will be mapped to V6 representation. If this option is turned off, then no mapping will be done of V4 addresses and a user will receive both PF_INET6 and PF_INET type addresses on the socket. See [RFC3542] for more details on mapped V6 addresses. This description isn't really in line with what the code does though. Introduce addr_to_user (renamed addr_v4map), which should be called before any sockaddr is passed back to user space. The new function places the sockaddr into the correct format depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. Audit all places that touched v4mapped and either sanely construct a v4 or v6 address then call addr_to_user, or drop the unnecessary v4mapped check entirely. Audit all places that call addr_to_user and verify they are on a sycall return path. Add a custom getname that formats the address properly. Several bugs are addressed: - SCTP_I_WANT_MAPPED_V4_ADDR=0 often returned garbage for addresses to user space - The addr_len returned from recvmsg was not correct when returning AF_INET on a v6 socket - flowlabel and scope_id were not zerod when promoting a v4 to v6 - Some syscalls like bind and connect behaved differently depending on v4mapped Tested bind, getpeername, getsockname, connect, and recvmsg for proper behaviour in v4mapped = 1 and 0 cases. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Tested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sctp/protocol.c')
-rw-r--r--net/sctp/protocol.c12
1 files changed, 6 insertions, 6 deletions
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index 6789d785e698..6240834f4b95 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -576,10 +576,10 @@ out:
return newsk;
}
-/* Map address, empty for v4 family */
-static void sctp_v4_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
+static int sctp_v4_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
{
- /* Empty */
+ /* No address mapping for V4 sockets */
+ return sizeof(struct sockaddr_in);
}
/* Dump the v4 addr to the seq file. */
@@ -976,7 +976,9 @@ static struct sctp_pf sctp_pf_inet = {
.send_verify = sctp_inet_send_verify,
.supported_addrs = sctp_inet_supported_addrs,
.create_accept_sk = sctp_v4_create_accept_sk,
- .addr_v4map = sctp_v4_addr_v4map,
+ .addr_to_user = sctp_v4_addr_to_user,
+ .to_sk_saddr = sctp_v4_to_sk_saddr,
+ .to_sk_daddr = sctp_v4_to_sk_daddr,
.af = &sctp_af_inet
};
@@ -1047,8 +1049,6 @@ static struct sctp_af sctp_af_inet = {
.copy_addrlist = sctp_v4_copy_addrlist,
.from_skb = sctp_v4_from_skb,
.from_sk = sctp_v4_from_sk,
- .to_sk_saddr = sctp_v4_to_sk_saddr,
- .to_sk_daddr = sctp_v4_to_sk_daddr,
.from_addr_param = sctp_v4_from_addr_param,
.to_addr_param = sctp_v4_to_addr_param,
.cmp_addr = sctp_v4_cmp_addr,