[PATCH] kexec: fix memory leak in function kimage_normal_alloc

[Zhang Yanfei]

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.

Cc: "Eric W. Biederman" <ebiederm at xmission.com>
Cc: Andrew Morton <akpm at linux-foundation.org>
Cc: Sasha Levin <sasha.levin at oracle.com>
Signed-off-by: Zhang Yanfei <zhangyanfei at cn.fujitsu.com>
---
 kernel/kexec.c |   18 ++++++++++--------
 1 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/kernel/kexec.c b/kernel/kexec.c
index 5e4bd78..a57face 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -223,6 +223,8 @@ 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)
@@ -248,22 +250,22 @@ 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;
 }
 
-- 
1.7.1