9p: fix multiple NULL-pointer-dereferences

Added checks to prevent GPFs from raising.

Link: http://lkml.kernel.org/r/20180727110558.5479-1-tomasbortoli@gmail.com
Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com>
Reported-by: syzbot+1a262da37d3bead15c39@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>

diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c
index 9642602..e2ef3c7 100644 (file)
--- a/net/9p/trans_fd.c
+++ b/net/9p/trans_fd.c
@@ -945,7 +945,7 @@ p9_fd_create_tcp(struct p9_client *client, const char *addr, char *args)
        if (err < 0)
                return err;
 
-       if (valid_ipaddr4(addr) < 0)
+       if (addr == NULL || valid_ipaddr4(addr) < 0)
                return -EINVAL;
 
        csocket = NULL;
@@ -995,6 +995,9 @@ p9_fd_create_unix(struct p9_client *client, const char *addr, char *args)
 
        csocket = NULL;
 
+       if (addr == NULL)
+               return -EINVAL;
+
        if (strlen(addr) >= UNIX_PATH_MAX) {
                pr_err("%s (%d): address too long: %s\n",
                       __func__, task_pid_nr(current), addr);

diff --git a/net/9p/trans_rdma.c b/net/9p/trans_rdma.c
index 2649b2e..2ab4574 100644 (file)
--- a/net/9p/trans_rdma.c
+++ b/net/9p/trans_rdma.c
@@ -645,6 +645,9 @@ rdma_create_trans(struct p9_client *client, const char *addr, char *args)
        struct rdma_conn_param conn_param;
        struct ib_qp_init_attr qp_attr;
 
+       if (addr == NULL)
+               return -EINVAL;
+
        /* Parse the transport specific mount options */
        err = parse_opts(args, &opts);
        if (err < 0)

diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index 06dcd3c..8ca356e 100644 (file)
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -654,6 +654,9 @@ p9_virtio_create(struct p9_client *client, const char *devname, char *args)
        int ret = -ENOENT;
        int found = 0;
 
+       if (devname == NULL)
+               return -EINVAL;
+
        mutex_lock(&virtio_9p_lock);
        list_for_each_entry(chan, &virtio_chan_list, chan_list) {
                if (!strncmp(devname, chan->tag, chan->tag_len) &&

diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c
index 2e2b8bc..c2d54ac 100644 (file)
--- a/net/9p/trans_xen.c
+++ b/net/9p/trans_xen.c
@@ -94,6 +94,9 @@ static int p9_xen_create(struct p9_client *client, const char *addr, char *args)
 {
        struct xen_9pfs_front_priv *priv;
 
+       if (addr == NULL)
+               return -EINVAL;
+
        read_lock(&xen_9pfs_lock);
        list_for_each_entry(priv, &xen_9pfs_devs, list) {
                if (!strcmp(priv->tag, addr)) {