1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c
index 51cc585faab9..e32c381eca7d 100644
--- a/drivers/dma-buf/udmabuf.c
+++ b/drivers/dma-buf/udmabuf.c
@@ -12,6 +12,9 @@
 #include <linux/slab.h>
 #include <linux/udmabuf.h>
 
+static const u32    list_limit = 1024;  /* udmabuf_create_list->count limit */
+static const size_t size_limit_mb = 64; /* total dmabuf size, in megabytes  */
+
 struct udmabuf {
         pgoff_t pagecount;
         struct page **pages;
@@ -123,7 +126,7 @@ static long udmabuf_create(const struct udmabuf_create_list *head,
         struct file *memfd = NULL;
         struct udmabuf *ubuf;
         struct dma_buf *buf;
-        pgoff_t pgoff, pgcnt, pgidx, pgbuf;
+        pgoff_t pgoff, pgcnt, pgidx, pgbuf, pglimit;
         struct page *page;
         int seals, ret = -EINVAL;
         u32 i, flags;
@@ -132,12 +135,15 @@ static long udmabuf_create(const struct udmabuf_create_list *head,
         if (!ubuf)
                 return -ENOMEM;
 
+        pglimit = (size_limit_mb * 1024 * 1024) >> PAGE_SHIFT;
         for (i = 0; i < head->count; i++) {
                 if (!IS_ALIGNED(list[i].offset, PAGE_SIZE))
                         goto err_free_ubuf;
                 if (!IS_ALIGNED(list[i].size, PAGE_SIZE))
                         goto err_free_ubuf;
                 ubuf->pagecount += list[i].size >> PAGE_SHIFT;
+                if (ubuf->pagecount > pglimit)
+                        goto err_free_ubuf;
         }
         ubuf->pages = kmalloc_array(ubuf->pagecount, sizeof(struct page *),
                                     GFP_KERNEL);
@@ -227,7 +233,7 @@ static long udmabuf_ioctl_create_list(struct file *filp, unsigned long arg)
 
         if (copy_from_user(&head, (void __user *)arg, sizeof(head)))
                 return -EFAULT;
-        if (head.count > 1024)
+        if (head.count > list_limit)
                 return -EINVAL;
         lsize = sizeof(struct udmabuf_create_item) * head.count;
         list = memdup_user((void __user *)(arg + sizeof(head)), lsize);