diff options
| author | Nicolas Dichtel <[email protected]> | 2017-10-11 16:24:48 +0200 |
|---|---|---|
| committer | David S. Miller <[email protected]> | 2017-10-16 20:52:43 +0100 |
| commit | 2459b4c635858094df78abb9ca87d99f89fe8ca5 (patch) | |
| tree | 8255b0b57d3acb2d5fe6099702dbfd9d87b09a82 | |
| parent | 2fd7c5abb8f35d6b701617f49aea9f0873284aee (diff) | |
net: enable interface alias removal via rtnl
IFLA_IFALIAS is defined as NLA_STRING. It means that the minimal length of
the attribute is 1 ("\0"). However, to remove an alias, the attribute
length must be 0 (see dev_set_alias()).
Let's define the type to NLA_BINARY to allow 0-length string, so that the
alias can be removed.
Example:
$ ip l s dummy0 alias foo
$ ip l l dev dummy0
5: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether ae:20:30:4f:a7:f3 brd ff:ff:ff:ff:ff:ff
alias foo
Before the patch:
$ ip l s dummy0 alias ""
RTNETLINK answers: Numerical result out of range
After the patch:
$ ip l s dummy0 alias ""
$ ip l l dev dummy0
5: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether ae:20:30:4f:a7:f3 brd ff:ff:ff:ff:ff:ff
CC: Oliver Hartkopp <[email protected]>
CC: Stephen Hemminger <[email protected]>
Fixes: 96ca4a2cc145 ("net: remove ifalias on empty given alias")
Reported-by: Julien FLoret <[email protected]>
Signed-off-by: Nicolas Dichtel <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
| -rw-r--r-- | net/core/rtnetlink.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index a6bcf86ce471..5ace48926b19 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1483,7 +1483,10 @@ static const struct nla_policy ifla_policy[IFLA_MAX+1] = { [IFLA_LINKINFO] = { .type = NLA_NESTED }, [IFLA_NET_NS_PID] = { .type = NLA_U32 }, [IFLA_NET_NS_FD] = { .type = NLA_U32 }, - [IFLA_IFALIAS] = { .type = NLA_STRING, .len = IFALIASZ-1 }, + /* IFLA_IFALIAS is a string, but policy is set to NLA_BINARY to + * allow 0-length string (needed to remove an alias). + */ + [IFLA_IFALIAS] = { .type = NLA_BINARY, .len = IFALIASZ - 1 }, [IFLA_VFINFO_LIST] = {. type = NLA_NESTED }, [IFLA_VF_PORTS] = { .type = NLA_NESTED }, [IFLA_PORT_SELF] = { .type = NLA_NESTED }, |