1 files changed, 14 insertions, 10 deletions

diff --git a/drivers/firewire/core-cdev.c b/drivers/firewire/core-cdev.c
index 8be720b278b7..14a34d99eea2 100644
--- a/drivers/firewire/core-cdev.c
+++ b/drivers/firewire/core-cdev.c
@@ -34,6 +34,7 @@
 #include <linux/mutex.h>
 #include <linux/poll.h>
 #include <linux/sched.h>
+#include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/string.h>
 #include <linux/time.h>
@@ -959,6 +960,8 @@ static int ioctl_queue_iso(struct client *client, union ioctl_arg *arg)
                 u.packet.header_length = GET_HEADER_LENGTH(control);
 
                 if (ctx->type == FW_ISO_CONTEXT_TRANSMIT) {
+                        if (u.packet.header_length % 4 != 0)
+                                return -EINVAL;
                         header_length = u.packet.header_length;
                 } else {
                         /*
@@ -968,7 +971,8 @@ static int ioctl_queue_iso(struct client *client, union ioctl_arg *arg)
                         if (ctx->header_size == 0) {
                                 if (u.packet.header_length > 0)
                                         return -EINVAL;
-                        } else if (u.packet.header_length % ctx->header_size != 0) {
+                        } else if (u.packet.header_length == 0 ||
+                                   u.packet.header_length % ctx->header_size != 0) {
                                 return -EINVAL;
                         }
                         header_length = 0;
@@ -1353,24 +1357,24 @@ static int dispatch_ioctl(struct client *client,
                 return -ENODEV;
 
         if (_IOC_TYPE(cmd) != '#' ||
-            _IOC_NR(cmd) >= ARRAY_SIZE(ioctl_handlers))
+            _IOC_NR(cmd) >= ARRAY_SIZE(ioctl_handlers) ||
+            _IOC_SIZE(cmd) > sizeof(buffer))
                 return -EINVAL;
 
-        if (_IOC_DIR(cmd) & _IOC_WRITE) {
-                if (_IOC_SIZE(cmd) > sizeof(buffer) ||
-                    copy_from_user(&buffer, arg, _IOC_SIZE(cmd)))
+        if (_IOC_DIR(cmd) == _IOC_READ)
+                memset(&buffer, 0, _IOC_SIZE(cmd));
+
+        if (_IOC_DIR(cmd) & _IOC_WRITE)
+                if (copy_from_user(&buffer, arg, _IOC_SIZE(cmd)))
                         return -EFAULT;
-        }
 
         ret = ioctl_handlers[_IOC_NR(cmd)](client, &buffer);
         if (ret < 0)
                 return ret;
 
-        if (_IOC_DIR(cmd) & _IOC_READ) {
-                if (_IOC_SIZE(cmd) > sizeof(buffer) ||
-                    copy_to_user(arg, &buffer, _IOC_SIZE(cmd)))
+        if (_IOC_DIR(cmd) & _IOC_READ)
+                if (copy_to_user(arg, &buffer, _IOC_SIZE(cmd)))
                         return -EFAULT;
-        }
 
         return ret;
 }