From b804defe4297157a9ff45863769efe9a01953398 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Thu, 14 Jan 2016 20:59:14 -0500 Subject: [PATCH] kexec: replace call to copy_file_from_fd() with kernel version 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 Acked-by: Kees Cook Acked-by: Luis R. Rodriguez Cc: Eric Biederman Acked-by: Dave Young --- 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 fb08b668c37a..52567252288e 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 007b791f676d..b696c3f3708f 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -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) { -- 2.34.1