Merge tag 'riscv-dt-for-v6.6-final' of https://git.kernel.org/pub/scm/linux/kernel...

[platform/kernel/linux-rpi.git] / io_uring / io_uring.c

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 783ed0f..d839a80 100644 (file)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -2686,7 +2686,7 @@ static void *__io_uaddr_map(struct page ***pages, unsigned short *npages,
 {
        struct page **page_array;
        unsigned int nr_pages;
-       int ret;
+       int ret, i;
 
        *npages = 0;
 
@@ -2716,6 +2716,20 @@ err:
         */
        if (page_array[0] != page_array[ret - 1])
                goto err;
+
+       /*
+        * Can't support mapping user allocated ring memory on 32-bit archs
+        * where it could potentially reside in highmem. Just fail those with
+        * -EINVAL, just like we did on kernels that didn't support this
+        * feature.
+        */
+       for (i = 0; i < nr_pages; i++) {
+               if (PageHighMem(page_array[i])) {
+                       ret = -EINVAL;
+                       goto err;
+               }
+       }
+
        *pages = page_array;
        *npages = nr_pages;
        return page_to_virt(page_array[0]);