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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/firmware/efi/libstub/file.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/firmware/efi/libstub/file.c')
-rw-r--r--drivers/firmware/efi/libstub/file.c309
1 files changed, 309 insertions, 0 deletions
diff --git a/drivers/firmware/efi/libstub/file.c b/drivers/firmware/efi/libstub/file.c
new file mode 100644
index 0000000000..d6a025df07
--- /dev/null
+++ b/drivers/firmware/efi/libstub/file.c
@@ -0,0 +1,309 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Helper functions used by the EFI stub on multiple
+ * architectures. This should be #included by the EFI stub
+ * implementation files.
+ *
+ * Copyright 2011 Intel Corporation; author Matt Fleming
+ */
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+#define MAX_FILENAME_SIZE 256
+
+/*
+ * Some firmware implementations have problems reading files in one go.
+ * A read chunk size of 1MB seems to work for most platforms.
+ *
+ * Unfortunately, reading files in chunks triggers *other* bugs on some
+ * platforms, so we provide a way to disable this workaround, which can
+ * be done by passing "efi=nochunk" on the EFI boot stub command line.
+ *
+ * If you experience issues with initrd images being corrupt it's worth
+ * trying efi=nochunk, but chunking is enabled by default on x86 because
+ * there are far more machines that require the workaround than those that
+ * break with it enabled.
+ */
+#define EFI_READ_CHUNK_SIZE SZ_1M
+
+struct finfo {
+ efi_file_info_t info;
+ efi_char16_t filename[MAX_FILENAME_SIZE];
+};
+
+static efi_status_t efi_open_file(efi_file_protocol_t *volume,
+ struct finfo *fi,
+ efi_file_protocol_t **handle,
+ unsigned long *file_size)
+{
+ efi_guid_t info_guid = EFI_FILE_INFO_ID;
+ efi_file_protocol_t *fh;
+ unsigned long info_sz;
+ efi_status_t status;
+ efi_char16_t *c;
+
+ /* Replace UNIX dir separators with EFI standard ones */
+ for (c = fi->filename; *c != L'\0'; c++) {
+ if (*c == L'/')
+ *c = L'\\';
+ }
+
+ status = efi_call_proto(volume, open, &fh, fi->filename,
+ EFI_FILE_MODE_READ, 0);
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to open file: %ls\n", fi->filename);
+ return status;
+ }
+
+ info_sz = sizeof(struct finfo);
+ status = efi_call_proto(fh, get_info, &info_guid, &info_sz, fi);
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to get file info\n");
+ efi_call_proto(fh, close);
+ return status;
+ }
+
+ *handle = fh;
+ *file_size = fi->info.file_size;
+ return EFI_SUCCESS;
+}
+
+static efi_status_t efi_open_volume(efi_loaded_image_t *image,
+ efi_file_protocol_t **fh)
+{
+ efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+ efi_simple_file_system_protocol_t *io;
+ efi_status_t status;
+
+ status = efi_bs_call(handle_protocol, efi_table_attr(image, device_handle),
+ &fs_proto, (void **)&io);
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to handle fs_proto\n");
+ return status;
+ }
+
+ status = efi_call_proto(io, open_volume, fh);
+ if (status != EFI_SUCCESS)
+ efi_err("Failed to open volume\n");
+
+ return status;
+}
+
+static int find_file_option(const efi_char16_t *cmdline, int cmdline_len,
+ const efi_char16_t *prefix, int prefix_size,
+ efi_char16_t *result, int result_len)
+{
+ int prefix_len = prefix_size / 2;
+ bool found = false;
+ int i;
+
+ for (i = prefix_len; i < cmdline_len; i++) {
+ if (!memcmp(&cmdline[i - prefix_len], prefix, prefix_size)) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found)
+ return 0;
+
+ /* Skip any leading slashes */
+ while (i < cmdline_len && (cmdline[i] == L'/' || cmdline[i] == L'\\'))
+ i++;
+
+ while (--result_len > 0 && i < cmdline_len) {
+ efi_char16_t c = cmdline[i++];
+
+ if (c == L'\0' || c == L'\n' || c == L' ')
+ break;
+ *result++ = c;
+ }
+ *result = L'\0';
+ return i;
+}
+
+static efi_status_t efi_open_device_path(efi_file_protocol_t **volume,
+ struct finfo *fi)
+{
+ efi_guid_t text_to_dp_guid = EFI_DEVICE_PATH_FROM_TEXT_PROTOCOL_GUID;
+ static efi_device_path_from_text_protocol_t *text_to_dp = NULL;
+ efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+ efi_device_path_protocol_t *initrd_dp;
+ efi_simple_file_system_protocol_t *io;
+ struct efi_file_path_dev_path *fpath;
+ efi_handle_t handle;
+ efi_status_t status;
+
+ /* See if the text to device path protocol exists */
+ if (!text_to_dp &&
+ efi_bs_call(locate_protocol, &text_to_dp_guid, NULL,
+ (void **)&text_to_dp) != EFI_SUCCESS)
+ return EFI_UNSUPPORTED;
+
+
+ /* Convert the filename wide string into a device path */
+ initrd_dp = efi_fn_call(text_to_dp, convert_text_to_device_path,
+ fi->filename);
+
+ /* Check whether the device path in question implements simple FS */
+ if ((efi_bs_call(locate_device_path, &fs_proto, &initrd_dp, &handle) ?:
+ efi_bs_call(handle_protocol, handle, &fs_proto, (void **)&io))
+ != EFI_SUCCESS)
+ return EFI_NOT_FOUND;
+
+ /* Check whether the remaining device path is a file device path */
+ if (initrd_dp->type != EFI_DEV_MEDIA ||
+ initrd_dp->sub_type != EFI_DEV_MEDIA_FILE) {
+ efi_warn("Unexpected device path node type: (%x, %x)\n",
+ initrd_dp->type, initrd_dp->sub_type);
+ return EFI_LOAD_ERROR;
+ }
+
+ /* Copy the remaining file path into the fi structure */
+ fpath = (struct efi_file_path_dev_path *)initrd_dp;
+ memcpy(fi->filename, fpath->filename,
+ min(sizeof(fi->filename),
+ fpath->header.length - sizeof(fpath->header)));
+
+ status = efi_call_proto(io, open_volume, volume);
+ if (status != EFI_SUCCESS)
+ efi_err("Failed to open volume\n");
+
+ return status;
+}
+
+/*
+ * Check the cmdline for a LILO-style file= arguments.
+ *
+ * We only support loading a file from the same filesystem as
+ * the kernel image.
+ */
+efi_status_t handle_cmdline_files(efi_loaded_image_t *image,
+ const efi_char16_t *optstr,
+ int optstr_size,
+ unsigned long soft_limit,
+ unsigned long hard_limit,
+ unsigned long *load_addr,
+ unsigned long *load_size)
+{
+ const efi_char16_t *cmdline = efi_table_attr(image, load_options);
+ u32 cmdline_len = efi_table_attr(image, load_options_size);
+ unsigned long efi_chunk_size = ULONG_MAX;
+ efi_file_protocol_t *volume = NULL;
+ efi_file_protocol_t *file;
+ unsigned long alloc_addr;
+ unsigned long alloc_size;
+ efi_status_t status;
+ int offset;
+
+ if (!load_addr || !load_size)
+ return EFI_INVALID_PARAMETER;
+
+ efi_apply_loadoptions_quirk((const void **)&cmdline, &cmdline_len);
+ cmdline_len /= sizeof(*cmdline);
+
+ if (IS_ENABLED(CONFIG_X86) && !efi_nochunk)
+ efi_chunk_size = EFI_READ_CHUNK_SIZE;
+
+ alloc_addr = alloc_size = 0;
+ do {
+ struct finfo fi;
+ unsigned long size;
+ void *addr;
+
+ offset = find_file_option(cmdline, cmdline_len,
+ optstr, optstr_size,
+ fi.filename, ARRAY_SIZE(fi.filename));
+
+ if (!offset)
+ break;
+
+ cmdline += offset;
+ cmdline_len -= offset;
+
+ status = efi_open_device_path(&volume, &fi);
+ if (status == EFI_UNSUPPORTED || status == EFI_NOT_FOUND)
+ /* try the volume that holds the kernel itself */
+ status = efi_open_volume(image, &volume);
+
+ if (status != EFI_SUCCESS)
+ goto err_free_alloc;
+
+ status = efi_open_file(volume, &fi, &file, &size);
+ if (status != EFI_SUCCESS)
+ goto err_close_volume;
+
+ /*
+ * Check whether the existing allocation can contain the next
+ * file. This condition will also trigger naturally during the
+ * first (and typically only) iteration of the loop, given that
+ * alloc_size == 0 in that case.
+ */
+ if (round_up(alloc_size + size, EFI_ALLOC_ALIGN) >
+ round_up(alloc_size, EFI_ALLOC_ALIGN)) {
+ unsigned long old_addr = alloc_addr;
+
+ status = EFI_OUT_OF_RESOURCES;
+ if (soft_limit < hard_limit)
+ status = efi_allocate_pages(alloc_size + size,
+ &alloc_addr,
+ soft_limit);
+ if (status == EFI_OUT_OF_RESOURCES)
+ status = efi_allocate_pages(alloc_size + size,
+ &alloc_addr,
+ hard_limit);
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to allocate memory for files\n");
+ goto err_close_file;
+ }
+
+ if (old_addr != 0) {
+ /*
+ * This is not the first time we've gone
+ * around this loop, and so we are loading
+ * multiple files that need to be concatenated
+ * and returned in a single buffer.
+ */
+ memcpy((void *)alloc_addr, (void *)old_addr, alloc_size);
+ efi_free(alloc_size, old_addr);
+ }
+ }
+
+ addr = (void *)alloc_addr + alloc_size;
+ alloc_size += size;
+
+ while (size) {
+ unsigned long chunksize = min(size, efi_chunk_size);
+
+ status = efi_call_proto(file, read, &chunksize, addr);
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to read file\n");
+ goto err_close_file;
+ }
+ addr += chunksize;
+ size -= chunksize;
+ }
+ efi_call_proto(file, close);
+ efi_call_proto(volume, close);
+ } while (offset > 0);
+
+ *load_addr = alloc_addr;
+ *load_size = alloc_size;
+
+ if (*load_size == 0)
+ return EFI_NOT_READY;
+ return EFI_SUCCESS;
+
+err_close_file:
+ efi_call_proto(file, close);
+
+err_close_volume:
+ efi_call_proto(volume, close);
+
+err_free_alloc:
+ efi_free(alloc_size, alloc_addr);
+ return status;
+}