projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| 18a2513c GKH |
1 | From foo@baz Tue Nov 28 10:56:34 CET 2017 |
| 2 | From: David Ahern <dsa@cumulusnetworks.com> | |
| 3 | Date: Thu, 29 Dec 2016 15:39:37 -0800 | |
| 4 | Subject: net: Allow IP_MULTICAST_IF to set index to L3 slave | |
| 5 | ||
| 6 | From: David Ahern <dsa@cumulusnetworks.com> | |
| 7 | ||
| 8 | ||
| 9 | [ Upstream commit 7bb387c5ab12aeac3d5eea28686489ff46b53ca9 ] | |
| 10 | ||
| 11 | IP_MULTICAST_IF fails if sk_bound_dev_if is already set and the new index | |
| 12 | does not match it. e.g., | |
| 13 | ||
| 14 | ntpd[15381]: setsockopt IP_MULTICAST_IF 192.168.1.23 fails: Invalid argument | |
| 15 | ||
| 16 | Relax the check in setsockopt to allow setting mc_index to an L3 slave if | |
| 17 | sk_bound_dev_if points to an L3 master. | |
| 18 | ||
| 19 | Make a similar change for IPv6. In this case change the device lookup to | |
| 20 | take the rcu_read_lock avoiding a refcnt. The rcu lock is also needed for | |
| 21 | the lookup of a potential L3 master device. | |
| 22 | ||
| 23 | This really only silences a setsockopt failure since uses of mc_index are | |
| 24 | secondary to sk_bound_dev_if if it is set. In both cases, if either index | |
| 25 | is an L3 slave or master, lookups are directed to the same FIB table so | |
| 26 | relaxing the check at setsockopt time causes no harm. | |
| 27 | ||
| 28 | Patch is based on a suggested change by Darwin for a problem noted in | |
| 29 | their code base. | |
| 30 | ||
| 31 | Suggested-by: Darwin Dingel <darwin.dingel@alliedtelesis.co.nz> | |
| 32 | Signed-off-by: David Ahern <dsa@cumulusnetworks.com> | |
| 33 | Signed-off-by: David S. Miller <davem@davemloft.net> | |
| 34 | Signed-off-by: Sasha Levin <alexander.levin@verizon.com> | |
| 35 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 36 | --- | |
| 37 | net/ipv4/ip_sockglue.c | 7 ++++++- | |
| 38 | net/ipv6/ipv6_sockglue.c | 16 ++++++++++++---- | |
| 39 | 2 files changed, 18 insertions(+), 5 deletions(-) | |
| 40 | ||
| 41 | --- a/net/ipv4/ip_sockglue.c | |
| 42 | +++ b/net/ipv4/ip_sockglue.c | |
| 43 | @@ -808,6 +808,7 @@ static int do_ip_setsockopt(struct sock | |
| 44 | { | |
| 45 | struct ip_mreqn mreq; | |
| 46 | struct net_device *dev = NULL; | |
| 47 | + int midx; | |
| 48 | ||
| 49 | if (sk->sk_type == SOCK_STREAM) | |
| 50 | goto e_inval; | |
| 51 | @@ -852,11 +853,15 @@ static int do_ip_setsockopt(struct sock | |
| 52 | err = -EADDRNOTAVAIL; | |
| 53 | if (!dev) | |
| 54 | break; | |
| 55 | + | |
| 56 | + midx = l3mdev_master_ifindex(dev); | |
| 57 | + | |
| 58 | dev_put(dev); | |
| 59 | ||
| 60 | err = -EINVAL; | |
| 61 | if (sk->sk_bound_dev_if && | |
| 62 | - mreq.imr_ifindex != sk->sk_bound_dev_if) | |
| 63 | + mreq.imr_ifindex != sk->sk_bound_dev_if && | |
| 64 | + (!midx || midx != sk->sk_bound_dev_if)) | |
| 65 | break; | |
| 66 | ||
| 67 | inet->mc_index = mreq.imr_ifindex; | |
| 68 | --- a/net/ipv6/ipv6_sockglue.c | |
| 69 | +++ b/net/ipv6/ipv6_sockglue.c | |
| 70 | @@ -583,16 +583,24 @@ done: | |
| 71 | ||
| 72 | if (val) { | |
| 73 | struct net_device *dev; | |
| 74 | + int midx; | |
| 75 | ||
| 76 | - if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != val) | |
| 77 | - goto e_inval; | |
| 78 | + rcu_read_lock(); | |
| 79 | ||
| 80 | - dev = dev_get_by_index(net, val); | |
| 81 | + dev = dev_get_by_index_rcu(net, val); | |
| 82 | if (!dev) { | |
| 83 | + rcu_read_unlock(); | |
| 84 | retv = -ENODEV; | |
| 85 | break; | |
| 86 | } | |
| 87 | - dev_put(dev); | |
| 88 | + midx = l3mdev_master_ifindex_rcu(dev); | |
| 89 | + | |
| 90 | + rcu_read_unlock(); | |
| 91 | + | |
| 92 | + if (sk->sk_bound_dev_if && | |
| 93 | + sk->sk_bound_dev_if != val && | |
| 94 | + (!midx || midx != sk->sk_bound_dev_if)) | |
| 95 | + goto e_inval; | |
| 96 | } | |
| 97 | np->mcast_oif = val; | |
| 98 | retv = 0; |