kimage_file_prepare_segments(): don't open-code memdup_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 4 insertions, 10 deletions

diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index b118735fea9d..766e7e4d3ad9 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -162,16 +162,10 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
         }
 
         if (cmdline_len) {
-                image->cmdline_buf = kzalloc(cmdline_len, GFP_KERNEL);
-                if (!image->cmdline_buf) {
-                        ret = -ENOMEM;
-                        goto out;
-                }
-
-                ret = copy_from_user(image->cmdline_buf, cmdline_ptr,
-                                     cmdline_len);
-                if (ret) {
-                        ret = -EFAULT;
+                image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len);
+                if (IS_ERR(image->cmdline_buf)) {
+                        ret = PTR_ERR(image->cmdline_buf);
+                        image->cmdline_buf = NULL;
                         goto out;
                 }