[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, 50 insertions, 17 deletions

diff --git a/net/bluetooth/bnep/sock.c b/net/bluetooth/bnep/sock.c
index 28c55835422a..5d9d6f14b310 100644
--- a/net/bluetooth/bnep/sock.c
+++ b/net/bluetooth/bnep/sock.c
@@ -43,6 +43,7 @@
 #include <linux/ioctl.h>
 #include <linux/file.h>
 #include <linux/init.h>
+#include <linux/compat.h>
 #include <net/sock.h>
 
 #include <asm/system.h>
@@ -146,24 +147,56 @@ static int bnep_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long
         return 0;
 }
 
+#ifdef CONFIG_COMPAT
+static int bnep_sock_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+        if (cmd == BNEPGETCONNLIST) {
+                struct bnep_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 = bnep_get_connlist(&cl);
+
+                if (!err && put_user(cl.cnum, (uint32_t __user *) arg))
+                        err = -EFAULT;
+
+                return err;
+        }
+
+        return bnep_sock_ioctl(sock, cmd, arg);
+}
+#endif
+
 static const struct proto_ops bnep_sock_ops = {
-        .family     = PF_BLUETOOTH,
-        .owner      = THIS_MODULE,
-        .release    = bnep_sock_release,
-        .ioctl      = bnep_sock_ioctl,
-        .bind       = sock_no_bind,
-        .getname    = sock_no_getname,
-        .sendmsg    = sock_no_sendmsg,
-        .recvmsg    = sock_no_recvmsg,
-        .poll       = sock_no_poll,
-        .listen     = sock_no_listen,
-        .shutdown   = sock_no_shutdown,
-        .setsockopt = sock_no_setsockopt,
-        .getsockopt = sock_no_getsockopt,
-        .connect    = sock_no_connect,
-        .socketpair = sock_no_socketpair,
-        .accept     = sock_no_accept,
-        .mmap       = sock_no_mmap
+        .family         = PF_BLUETOOTH,
+        .owner          = THIS_MODULE,
+        .release        = bnep_sock_release,
+        .ioctl          = bnep_sock_ioctl,
+#ifdef CONFIG_COMPAT
+        .compat_ioctl   = bnep_sock_compat_ioctl,
+#endif
+        .bind           = sock_no_bind,
+        .getname        = sock_no_getname,
+        .sendmsg        = sock_no_sendmsg,
+        .recvmsg        = sock_no_recvmsg,
+        .poll           = sock_no_poll,
+        .listen         = sock_no_listen,
+        .shutdown       = sock_no_shutdown,
+        .setsockopt     = sock_no_setsockopt,
+        .getsockopt     = sock_no_getsockopt,
+        .connect        = sock_no_connect,
+        .socketpair     = sock_no_socketpair,
+        .accept         = sock_no_accept,
+        .mmap           = sock_no_mmap
 };
 
 static struct proto bnep_proto = {