[Bluetooth] Fix compat ioctl for BNEP, CMTP and HIDP

There exists no attempt do deal with the fact that a structure with
a uint32_t followed by a pointer is going to be different for 32-bit
and 64-bit userspace. Any 32-bit process trying to use it will be
failing with -EFAULT if it's lucky; suffering from having data dumped
at a random address if it's not.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 78 insertions, 0 deletions

diff --git a/net/bluetooth/hidp/sock.c b/net/bluetooth/hidp/sock.c
index 099646e4e2ef..6242446aa270 100644
--- a/net/bluetooth/hidp/sock.c
+++ b/net/bluetooth/hidp/sock.c
@@ -35,6 +35,7 @@
 #include <linux/ioctl.h>
 #include <linux/file.h>
 #include <linux/init.h>
+#include <linux/compat.h>
 #include <net/sock.h>
 
 #include "hidp.h"
@@ -143,11 +144,88 @@ static int hidp_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long
         return -EINVAL;
 }
 
+#ifdef CONFIG_COMPAT
+struct compat_hidp_connadd_req {
+        int   ctrl_sock;        // Connected control socket
+        int   intr_sock;        // Connteted interrupt socket
+        __u16 parser;
+        __u16 rd_size;
+        compat_uptr_t rd_data;
+        __u8  country;
+        __u8  subclass;
+        __u16 vendor;
+        __u16 product;
+        __u16 version;
+        __u32 flags;
+        __u32 idle_to;
+        char  name[128];
+};
+
+static int hidp_sock_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+        if (cmd == HIDPGETCONNLIST) {
+                struct hidp_connlist_req cl;
+                uint32_t uci;
+                int err;
+
+                if (get_user(cl.cnum, (uint32_t __user *) arg) ||
+                                get_user(uci, (u32 __user *) (arg + 4)))
+                        return -EFAULT;
+
+                cl.ci = compat_ptr(uci);
+
+                if (cl.cnum <= 0)
+                        return -EINVAL;
+
+                err = hidp_get_connlist(&cl);
+
+                if (!err && put_user(cl.cnum, (uint32_t __user *) arg))
+                        err = -EFAULT;
+
+                return err;
+        } else if (cmd == HIDPCONNADD) {
+                struct compat_hidp_connadd_req ca;
+                struct hidp_connadd_req __user *uca;
+
+                uca = compat_alloc_user_space(sizeof(*uca));
+
+                if (copy_from_user(&ca, (void *) arg, sizeof(ca)))
+                        return -EFAULT;
+
+                if (put_user(ca.ctrl_sock, &uca->ctrl_sock) ||
+                                put_user(ca.intr_sock, &uca->intr_sock) ||
+                                put_user(ca.parser, &uca->parser) ||
+                                put_user(ca.rd_size, &uca->parser) ||
+                                put_user(compat_ptr(ca.rd_data), &uca->rd_data) ||
+                                put_user(ca.country, &uca->country) ||
+                                put_user(ca.subclass, &uca->subclass) ||
+                                put_user(ca.vendor, &uca->vendor) ||
+                                put_user(ca.product, &uca->product) ||
+                                put_user(ca.version, &uca->version) ||
+                                put_user(ca.flags, &uca->flags) ||
+                                put_user(ca.idle_to, &uca->idle_to) ||
+                                copy_to_user(&uca->name[0], &ca.name[0], 128))
+                        return -EFAULT;
+                
+                arg = (unsigned long) uca;
+
+                /* Fall through. We don't actually write back any _changes_
+                   to the structure anyway, so there's no need to copy back
+                   into the original compat version */
+        }
+
+        return hidp_sock_ioctl(sock, cmd, arg);
+}
+#endif
+
 static const struct proto_ops hidp_sock_ops = {
         .family         = PF_BLUETOOTH,
         .owner          = THIS_MODULE,
         .release        = hidp_sock_release,
         .ioctl          = hidp_sock_ioctl,
+#ifdef CONFIG_COMPAT
+        .compat_ioctl   = hidp_sock_compat_ioctl,
+#endif
         .bind           = sock_no_bind,
         .getname        = sock_no_getname,
         .sendmsg        = sock_no_sendmsg,