efi/libstub: Use snprintf with %ls to convert the command line (04b24409) · Commits · 戴 / test

drivers/firmware/efi/libstub/efi-stub-helper.c

+6 −60

Original line number	Diff line number	Diff line
		@@ -205,46 +205,6 @@ efi_status_t efi_parse_options(char const *cmdline)
		return EFI_SUCCESS;
		}

		/*
		* Convert an UTF-16 string, not necessarily null terminated, to UTF-8.
		*/
		static u8 efi_utf16_to_utf8(u8 dst, const u16 *src, int n)
		{
		unsigned int c;

		while (n--) {
		c = *src++;
		if (n && c >= 0xd800 && c <= 0xdbff &&
		src >= 0xdc00 && src <= 0xdfff) {
		c = 0x10000 + ((c & 0x3ff) << 10) + (*src & 0x3ff);
		src++;
		n--;
		}
		if (c >= 0xd800 && c <= 0xdfff)
		c = 0xfffd; /* Unmatched surrogate */
		if (c < 0x80) {
		*dst++ = c;
		continue;
		}
		if (c < 0x800) {
		*dst++ = 0xc0 + (c >> 6);
		goto t1;
		}
		if (c < 0x10000) {
		*dst++ = 0xe0 + (c >> 12);
		goto t2;
		}
		*dst++ = 0xf0 + (c >> 18);
		*dst++ = 0x80 + ((c >> 12) & 0x3f);
		t2:
		*dst++ = 0x80 + ((c >> 6) & 0x3f);
		t1:
		*dst++ = 0x80 + (c & 0x3f);
		}

		return dst;
		}

		/*
		* Convert the unicode UEFI command line to ASCII to pass to kernel.
		* Size of memory allocated return in *cmd_line_len.
		@@ -254,18 +214,15 @@ char efi_convert_cmdline(efi_loaded_image_t image,
		int *cmd_line_len, unsigned long max_addr)
		{
		const u16 *s2;
		u8 *s1 = NULL;
		unsigned long cmdline_addr = 0;
		int load_options_chars = efi_table_attr(image, load_options_size) / 2;
		int options_chars = efi_table_attr(image, load_options_size) / 2;
		const u16 *options = efi_table_attr(image, load_options);
		int options_bytes = 0; /* UTF-8 bytes */
		int options_chars = 0; /* UTF-16 chars */
		efi_status_t status;
		u16 zero = 0;

		if (options) {
		s2 = options;
		while (options_chars < load_options_chars) {
		while (options_chars--) {
		u16 c = *s2++;

		if (c == L'\0' \|\| c == L'\n')
		@@ -276,7 +233,6 @@ char efi_convert_cmdline(efi_loaded_image_t image,
		* The first part handles everything in the BMP.
		*/
		options_bytes += 1 + (c >= 0x80) + (c >= 0x800);
		options_chars++;
		/*
		* Add one more byte for valid surrogate pairs. Invalid
		* surrogates will be replaced with 0xfffd and take up
		@@ -288,35 +244,25 @@ char efi_convert_cmdline(efi_loaded_image_t image,
		* we must ignore it since we can't access the
		* low surrogate.
		*/
		if (options_chars == load_options_chars) {
		if (!options_chars) {
		options_bytes -= 3;
		options_chars--;
		break;
		} else if ((*s2 & 0xfc00) == 0xdc00) {
		options_bytes++;
		options_chars++;
		options_chars--;
		s2++;
		}
		}
		}
		}

		if (!options_chars) {
		/* No command line options, so return empty string*/
		options = &zero;
		}

		options_bytes++; /* NUL termination */

		status = efi_allocate_pages(options_bytes, &cmdline_addr, max_addr);
		if (status != EFI_SUCCESS)
		return NULL;

		s1 = (u8 *)cmdline_addr;
		s2 = (const u16 *)options;

		s1 = efi_utf16_to_utf8(s1, s2, options_chars);
		*s1 = '\0';
		snprintf((char )cmdline_addr, options_bytes, "%.ls",
		options_bytes - 1, options);

		*cmd_line_len = options_bytes;
		return (char *)cmdline_addr;

Admin message