mm/gup: fix memory leak in __gup_benchmark_ioctl

In the implementation of __gup_benchmark_ioctl() the allocated pages
should be released before returning in case of an invalid cmd.  Release
pages via kvfree().

[akpm@linux-foundation.org: rework code flow, return -EINVAL rather than -1]
Link: http://lkml.kernel.org/r/20191211174653.4102-1-navid.emamdoost@gmail.com
Fixes: 714a3a1ebafe ("mm/gup_benchmark.c: add additional pinning methods")
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c
index 7dd602d..ad9d5b1 100644 (file)
--- a/mm/gup_benchmark.c
+++ b/mm/gup_benchmark.c
@@ -26,6 +26,7 @@ static int __gup_benchmark_ioctl(unsigned int cmd,
        unsigned long i, nr_pages, addr, next;
        int nr;
        struct page **pages;
+       int ret = 0;
 
        if (gup->size > ULONG_MAX)
                return -EINVAL;
@@ -63,7 +64,9 @@ static int __gup_benchmark_ioctl(unsigned int cmd,
                                            NULL);
                        break;
                default:
-                       return -1;
+                       kvfree(pages);
+                       ret = -EINVAL;
+                       goto out;
                }
 
                if (nr <= 0)
@@ -85,7 +88,8 @@ static int __gup_benchmark_ioctl(unsigned int cmd,
        gup->put_delta_usec = ktime_us_delta(end_time, start_time);
 
        kvfree(pages);
-       return 0;
+out:
+       return ret;
 }
 
 static long gup_benchmark_ioctl(struct file *filep, unsigned int cmd,