| Message ID | 20140226135000.11521.30339.stgit@localhost.localdomain (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Applying, sorry for the delay.--b. On Wed, Feb 26, 2014 at 04:50:01PM +0300, Stanislav Kinsbursky wrote: > There could be a case, when NFSd file system is mounted in network, different > to socket's one, like below: > > "ip netns exec" creates new network and mount namespace, which duplicates NFSd > mount point, created in init_net context. And thus NFS server stop in nested > network context leads to RPCBIND client destruction in init_net. > Then, on NFSd start in nested network context, rpc.nfsd process creates socket > in nested net and passes it into "write_ports", which leads to RPCBIND sockets > creation in init_net context because of the same reason (NFSd monut point was > created in init_net context). An attempt to register passed socket in nested > net leads to panic, because no RPCBIND client present in nexted network > namespace. > > This patch add check that passed socket's net matches NFSd superblock's one. > And returns -EINVAL error to user psace otherwise. > > v2: Put socket on exit. > > Reported-by: Weng Meiling <wengmeiling.weng@huawei.com> > Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> > Cc: stable@vger.kernel.org > --- > fs/nfsd/nfsctl.c | 5 +++++ > include/linux/sunrpc/svcsock.h | 1 + > net/sunrpc/svcsock.c | 16 ++++++++++++++++ > 3 files changed, 22 insertions(+), 0 deletions(-) > > diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c > index 7f55517..f34d9de 100644 > --- a/fs/nfsd/nfsctl.c > +++ b/fs/nfsd/nfsctl.c > @@ -699,6 +699,11 @@ static ssize_t __write_ports_addfd(char *buf, struct net *net) > if (err != 0 || fd < 0) > return -EINVAL; > > + if (svc_alien_sock(net, fd)) { > + printk(KERN_ERR "%s: socket net is different to NFSd's one\n", __func__); > + return -EINVAL; > + } > + > err = nfsd_create_serv(net); > if (err != 0) > return err; > diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h > index 62fd1b7..947009e 100644 > --- a/include/linux/sunrpc/svcsock.h > +++ b/include/linux/sunrpc/svcsock.h > @@ -56,6 +56,7 @@ int svc_recv(struct svc_rqst *, long); > int svc_send(struct svc_rqst *); > void svc_drop(struct svc_rqst *); > void svc_sock_update_bufs(struct svc_serv *serv); > +bool svc_alien_sock(struct net *net, int fd); > int svc_addsock(struct svc_serv *serv, const int fd, > char *name_return, const size_t len); > void svc_init_xprt_sock(void); > diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c > index b6e59f0..d06cb87 100644 > --- a/net/sunrpc/svcsock.c > +++ b/net/sunrpc/svcsock.c > @@ -1397,6 +1397,22 @@ static struct svc_sock *svc_setup_socket(struct svc_serv *serv, > return svsk; > } > > +bool svc_alien_sock(struct net *net, int fd) > +{ > + int err; > + struct socket *sock = sockfd_lookup(fd, &err); > + bool ret = false; > + > + if (!sock) > + goto out; > + if (sock_net(sock->sk) != net) > + ret = true; > + sockfd_put(sock); > +out: > + return ret; > +} > +EXPORT_SYMBOL_GPL(svc_alien_sock); > + > /** > * svc_addsock - add a listener socket to an RPC service > * @serv: pointer to RPC service to which to add a new listener > -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index 7f55517..f34d9de 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -699,6 +699,11 @@ static ssize_t __write_ports_addfd(char *buf, struct net *net) if (err != 0 || fd < 0) return -EINVAL; + if (svc_alien_sock(net, fd)) { + printk(KERN_ERR "%s: socket net is different to NFSd's one\n", __func__); + return -EINVAL; + } + err = nfsd_create_serv(net); if (err != 0) return err; diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h index 62fd1b7..947009e 100644 --- a/include/linux/sunrpc/svcsock.h +++ b/include/linux/sunrpc/svcsock.h @@ -56,6 +56,7 @@ int svc_recv(struct svc_rqst *, long); int svc_send(struct svc_rqst *); void svc_drop(struct svc_rqst *); void svc_sock_update_bufs(struct svc_serv *serv); +bool svc_alien_sock(struct net *net, int fd); int svc_addsock(struct svc_serv *serv, const int fd, char *name_return, const size_t len); void svc_init_xprt_sock(void); diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index b6e59f0..d06cb87 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -1397,6 +1397,22 @@ static struct svc_sock *svc_setup_socket(struct svc_serv *serv, return svsk; } +bool svc_alien_sock(struct net *net, int fd) +{ + int err; + struct socket *sock = sockfd_lookup(fd, &err); + bool ret = false; + + if (!sock) + goto out; + if (sock_net(sock->sk) != net) + ret = true; + sockfd_put(sock); +out: + return ret; +} +EXPORT_SYMBOL_GPL(svc_alien_sock); + /** * svc_addsock - add a listener socket to an RPC service * @serv: pointer to RPC service to which to add a new listener
There could be a case, when NFSd file system is mounted in network, different to socket's one, like below: "ip netns exec" creates new network and mount namespace, which duplicates NFSd mount point, created in init_net context. And thus NFS server stop in nested network context leads to RPCBIND client destruction in init_net. Then, on NFSd start in nested network context, rpc.nfsd process creates socket in nested net and passes it into "write_ports", which leads to RPCBIND sockets creation in init_net context because of the same reason (NFSd monut point was created in init_net context). An attempt to register passed socket in nested net leads to panic, because no RPCBIND client present in nexted network namespace. This patch add check that passed socket's net matches NFSd superblock's one. And returns -EINVAL error to user psace otherwise. v2: Put socket on exit. Reported-by: Weng Meiling <wengmeiling.weng@huawei.com> Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Cc: stable@vger.kernel.org --- fs/nfsd/nfsctl.c | 5 +++++ include/linux/sunrpc/svcsock.h | 1 + net/sunrpc/svcsock.c | 16 ++++++++++++++++ 3 files changed, 22 insertions(+), 0 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html