mm/gup_benchmark.c: prevent integer overflow in ioctl

[linux-2.6-block.git] / mm / gup_benchmark.c

diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c
index 7405c9d89d65134c003a2d3984e1a993fd9c9907..5b42d3d4b60aa3a921002abf8f2872bc6e0764f8 100644 (file)
--- a/mm/gup_benchmark.c
+++ b/mm/gup_benchmark.c
@@ -6,13 +6,17 @@
 #include <linux/debugfs.h>
 
 #define GUP_FAST_BENCHMARK     _IOWR('g', 1, struct gup_benchmark)
+#define GUP_LONGTERM_BENCHMARK _IOWR('g', 2, struct gup_benchmark)
+#define GUP_BENCHMARK          _IOWR('g', 3, struct gup_benchmark)
 
 struct gup_benchmark {
-       __u64 delta_usec;
+       __u64 get_delta_usec;
+       __u64 put_delta_usec;
        __u64 addr;
        __u64 size;
        __u32 nr_pages_per_call;
        __u32 flags;
+       __u64 expansion[10];    /* For future use */
 };
 
 static int __gup_benchmark_ioctl(unsigned int cmd,
@@ -23,6 +27,9 @@ static int __gup_benchmark_ioctl(unsigned int cmd,
        int nr;
        struct page **pages;
 
+       if (gup->size > ULONG_MAX)
+               return -EINVAL;
+
        nr_pages = gup->size / PAGE_SIZE;
        pages = kvcalloc(nr_pages, sizeof(void *), GFP_KERNEL);
        if (!pages)
@@ -41,21 +48,40 @@ static int __gup_benchmark_ioctl(unsigned int cmd,
                        nr = (next - addr) / PAGE_SIZE;
                }
 
-               nr = get_user_pages_fast(addr, nr, gup->flags & 1, pages + i);
+               switch (cmd) {
+               case GUP_FAST_BENCHMARK:
+                       nr = get_user_pages_fast(addr, nr, gup->flags & 1,
+                                                pages + i);
+                       break;
+               case GUP_LONGTERM_BENCHMARK:
+                       nr = get_user_pages_longterm(addr, nr, gup->flags & 1,
+                                                    pages + i, NULL);
+                       break;
+               case GUP_BENCHMARK:
+                       nr = get_user_pages(addr, nr, gup->flags & 1, pages + i,
+                                           NULL);
+                       break;
+               default:
+                       return -1;
+               }
+
                if (nr <= 0)
                        break;
                i += nr;
        }
        end_time = ktime_get();
 
-       gup->delta_usec = ktime_us_delta(end_time, start_time);
+       gup->get_delta_usec = ktime_us_delta(end_time, start_time);
        gup->size = addr - gup->addr;
 
+       start_time = ktime_get();
        for (i = 0; i < nr_pages; i++) {
                if (!pages[i])
                        break;
                put_page(pages[i]);
        }
+       end_time = ktime_get();
+       gup->put_delta_usec = ktime_us_delta(end_time, start_time);
 
        kvfree(pages);
        return 0;
@@ -67,8 +93,14 @@ static long gup_benchmark_ioctl(struct file *filep, unsigned int cmd,
        struct gup_benchmark gup;
        int ret;
 
-       if (cmd != GUP_FAST_BENCHMARK)
+       switch (cmd) {
+       case GUP_FAST_BENCHMARK:
+       case GUP_LONGTERM_BENCHMARK:
+       case GUP_BENCHMARK:
+               break;
+       default:
                return -EINVAL;
+       }
 
        if (copy_from_user(&gup, (void __user *)arg, sizeof(gup)))
                return -EFAULT;