Check the parameters passed to Write():
* cannot write to directories (UEFI SCT 2017, 5.7.3.5.15) * cannot write to file opened read only (UEFI SCT 2017, 5.7.3.5.16)
Add missing comments.
Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de --- lib/efi_loader/efi_file.c | 51 +++++++++++++++++++++++++++++++-------- 1 file changed, 41 insertions(+), 10 deletions(-)
diff --git a/lib/efi_loader/efi_file.c b/lib/efi_loader/efi_file.c index f4ca5694ee..a13754a558 100644 --- a/lib/efi_loader/efi_file.c +++ b/lib/efi_loader/efi_file.c @@ -1,8 +1,8 @@ // SPDX-License-Identifier: GPL-2.0+ /* - * EFI utils + * EFI_FILE_PROTOCOL * - * Copyright (c) 2017 Rob Clark + * Copyright (c) 2017 Rob Clark */
#include <common.h> @@ -28,6 +28,7 @@ struct file_handle { struct file_system *fs; loff_t offset; /* current file position/cursor */ int isdir; + u64 open_mode;
/* for reading a directory: */ struct fs_dir_stream *dirs; @@ -161,13 +162,13 @@ static int efi_create_file(struct file_handle *fh, u64 attributes) * @file_name: path of the file to be opened. '', '.', or '..' may * be used as modifiers. A leading backslash indicates an * absolute path. - * @mode: bit mask indicating the access mode (read, write, + * @open_mode: bit mask indicating the access mode (read, write, * create) * @attributes: attributes for newly created file * Returns: handle to the opened file or NULL */ static struct efi_file_handle *file_open(struct file_system *fs, - struct file_handle *parent, u16 *file_name, u64 mode, + struct file_handle *parent, u16 *file_name, u64 open_mode, u64 attributes) { struct file_handle *fh; @@ -190,6 +191,7 @@ static struct efi_file_handle *file_open(struct file_system *fs, /* +2 is for null and '/' */ fh = calloc(1, sizeof(*fh) + plen + (flen * MAX_UTF8_PER_UTF16) + 2);
+ fh->open_mode = open_mode; fh->base = efi_file_handle_protocol; fh->fs = fs;
@@ -218,9 +220,11 @@ static struct efi_file_handle *file_open(struct file_system *fs, goto error;
if (!exists) { - if (!(mode & EFI_FILE_MODE_CREATE) || + if (!(open_mode & EFI_FILE_MODE_CREATE) || efi_create_file(fh, attributes)) goto error; + if (set_blk_dev(fh)) + goto error; }
/* figure out if file is a directory: */ @@ -434,6 +438,19 @@ error: return EFI_EXIT(ret); }
+/** + * efi_file_write() - write to file + * + * This function implements the Write() service of the EFI_FILE_PROTOCOL. + * + * See the Unified Extensible Firmware Interface (UEFI) specification for + * details. + * + * @file: file handle + * @buffer_size: number of bytes to write + * @buffer: buffer with the bytes to write + * Return: status code + */ static efi_status_t EFIAPI efi_file_write(struct efi_file_handle *file, efi_uintn_t *buffer_size, void *buffer) @@ -444,21 +461,35 @@ static efi_status_t EFIAPI efi_file_write(struct efi_file_handle *file,
EFI_ENTRY("%p, %p, %p", file, buffer_size, buffer);
+ if (!file || !buffer_size || !buffer) { + ret = EFI_INVALID_PARAMETER; + goto out; + } + if (fh->isdir) { + ret = EFI_UNSUPPORTED; + goto out; + } + if (!(fh->open_mode & EFI_FILE_MODE_WRITE)) { + ret = EFI_ACCESS_DENIED; + goto out; + } + + if (!*buffer_size) + goto out; + if (set_blk_dev(fh)) { ret = EFI_DEVICE_ERROR; - goto error; + goto out; } - if (fs_write(fh->path, map_to_sysmem(buffer), fh->offset, *buffer_size, &actwrite)) { ret = EFI_DEVICE_ERROR; - goto error; + goto out; } - *buffer_size = actwrite; fh->offset += actwrite;
-error: +out: return EFI_EXIT(ret); }
-- 2.20.1