kexec: fix memory leak in function kimage_normal_alloc

If kimage_normal_alloc() fails to alloc pages for image->swap_page, it
should call kimage_free_page_list() to free allocated pages in
image->control_pages list before it frees image.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Reviewed-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 10 insertions, 8 deletions

diff --git a/kernel/kexec.c b/kernel/kexec.c
index 855bfbbf4048..6b7455e3c96b 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -229,6 +229,8 @@ out:
 
 }
 
+static void kimage_free_page_list(struct list_head *list);
+
 static int kimage_normal_alloc(struct kimage **rimage, unsigned long entry,
                                 unsigned long nr_segments,
                                 struct kexec_segment __user *segments)
@@ -252,22 +254,22 @@ static int kimage_normal_alloc(struct kimage **rimage, unsigned long entry,
                                            get_order(KEXEC_CONTROL_PAGE_SIZE));
         if (!image->control_code_page) {
                 printk(KERN_ERR "Could not allocate control_code_buffer\n");
-                goto out;
+                goto out_free;
         }
 
         image->swap_page = kimage_alloc_control_pages(image, 0);
         if (!image->swap_page) {
                 printk(KERN_ERR "Could not allocate swap buffer\n");
-                goto out;
+                goto out_free;
         }
 
-        result = 0;
- out:
-        if (result == 0)
-                *rimage = image;
-        else
-                kfree(image);
+        *rimage = image;
+        return 0;
 
+out_free:
+        kimage_free_page_list(&image->control_pages);
+        kfree(image);
+out:
         return result;
 }