Replace copy_file_from_fd() with kernel_read_file_from_fd().
Two new identifiers named READING_KEXEC_IMAGE and READING_KEXEC_INITRAMFS
are defined for measuring, appraising or auditing the kexec image and
initramfs.
Changelog v3:
- return -EBADF, not -ENOEXEC
- identifier change
- split patch, moving copy_file_from_fd() to a separate patch
- split patch, moving IMA changes to a separate patch
v0:
- use kstat file size type loff_t, not size_t
- Calculate the file hash from the in memory buffer - Dave Young
Signed-off-by: Mimi Zohar <zohar at linux.vnet.ibm.com>
Acked-by: Kees Cook <keescook at chromium.org>
Acked-by: Luis R. Rodriguez <mcgrof at kernel.org>
Cc: Eric Biederman <ebiederm at xmission.com>
Acked-by: Dave Young <dyoung at redhat.com>
---
include/linux/fs.h | 2 ++
kernel/kexec_file.c | 73 +++++++----------------------------------------------
2 files changed, 11 insertions(+), 64 deletions(-)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index fb08b66..5256725 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2579,6 +2579,8 @@ extern int do_pipe_flags(int *, int);
enum kernel_read_file_id {
READING_FIRMWARE = 1,
READING_MODULE,
+ READING_KEXEC_IMAGE,
+ READING_KEXEC_INITRAMFS,
READING_MAX_ID
};
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 007b791..b696c3f 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -18,6 +18,7 @@
#include <linux/kexec.h>
#include <linux/mutex.h>
#include <linux/list.h>
+#include <linux/fs.h>
#include <crypto/hash.h>
#include <crypto/sha.h>
#include <linux/syscalls.h>
@@ -33,65 +34,6 @@ size_t __weak kexec_purgatory_size = 0;
static int kexec_calculate_store_digests(struct kimage *image);
-static int copy_file_from_fd(int fd, void **buf, unsigned long *buf_len)
-{
- struct fd f = fdget(fd);
- int ret;
- struct kstat stat;
- loff_t pos;
- ssize_t bytes = 0;
-
- if (!f.file)
- return -EBADF;
-
- ret = vfs_getattr(&f.file->f_path, &stat);
- if (ret)
- goto out;
-
- if (stat.size > INT_MAX) {
- ret = -EFBIG;
- goto out;
- }
-
- /* Don't hand 0 to vmalloc, it whines. */
- if (stat.size == 0) {
- ret = -EINVAL;
- goto out;
- }
-
- *buf = vmalloc(stat.size);
- if (!*buf) {
- ret = -ENOMEM;
- goto out;
- }
-
- pos = 0;
- while (pos < stat.size) {
- bytes = kernel_read(f.file, pos, (char *)(*buf) + pos,
- stat.size - pos);
- if (bytes < 0) {
- vfree(*buf);
- ret = bytes;
- goto out;
- }
-
- if (bytes == 0)
- break;
- pos += bytes;
- }
-
- if (pos != stat.size) {
- ret = -EBADF;
- vfree(*buf);
- goto out;
- }
-
- *buf_len = pos;
-out:
- fdput(f);
- return ret;
-}
-
/* Architectures can provide this probe function */
int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
unsigned long buf_len)
@@ -182,16 +124,17 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
{
int ret = 0;
void *ldata;
+ loff_t size;
- ret = copy_file_from_fd(kernel_fd, &image->kernel_buf,
- &image->kernel_buf_len);
+ ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf,
+ &size, INT_MAX, READING_KEXEC_IMAGE);
if (ret)
return ret;
+ image->kernel_buf_len = size;
/* Call arch image probe handlers */
ret = arch_kexec_kernel_image_probe(image, image->kernel_buf,
image->kernel_buf_len);
-
if (ret)
goto out;
@@ -206,10 +149,12 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
#endif
/* It is possible that there no initramfs is being loaded */
if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
- ret = copy_file_from_fd(initrd_fd, &image->initrd_buf,
- &image->initrd_buf_len);
+ ret = kernel_read_file_from_fd(initrd_fd, &image->initrd_buf,
+ &size, INT_MAX,
+ READING_KEXEC_INITRAMFS);
if (ret)
goto out;
+ image->initrd_buf_len = size;
}
if (cmdline_len) {
--
2.1.0
