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author | H. Peter Anvin <hpa@linux.intel.com> | 2013-09-20 09:55:39 -0500 |
---|---|---|
committer | Matt Fleming <matt.fleming@intel.com> | 2014-04-17 12:29:25 +0100 |
commit | c625d1c203941fad755eb4eb729db1f65d6e9836 (patch) | |
tree | 2b1cf021ceb69963092ec5db8fbb83c356b81f75 | |
parent | 9bb40191e88d23563fd0467ac195debf5f6daaf9 (diff) | |
download | linux-stable-c625d1c203941fad755eb4eb729db1f65d6e9836.tar.gz linux-stable-c625d1c203941fad755eb4eb729db1f65d6e9836.tar.bz2 linux-stable-c625d1c203941fad755eb4eb729db1f65d6e9836.zip |
efi: x86: Handle arbitrary Unicode characters
Instead of truncating UTF-16 assuming all characters is ASCII,
properly convert it to UTF-8.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
[ Bug and style fixes. ]
Signed-off-by: Roy Franz <roy.franz@linaro.org>
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
-rw-r--r-- | arch/x86/boot/compressed/eboot.c | 3 | ||||
-rw-r--r-- | drivers/firmware/efi/efi-stub-helper.c | 87 |
2 files changed, 68 insertions, 22 deletions
diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index 4703a6c4b8e3..0331d765c2bb 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -1087,8 +1087,7 @@ struct boot_params *make_boot_params(struct efi_config *c) hdr->type_of_loader = 0x21; /* Convert unicode cmdline to ascii */ - cmdline_ptr = efi_convert_cmdline_to_ascii(sys_table, image, - &options_size); + cmdline_ptr = efi_convert_cmdline(sys_table, image, &options_size); if (!cmdline_ptr) goto fail; hdr->cmd_line_ptr = (unsigned long)cmdline_ptr; diff --git a/drivers/firmware/efi/efi-stub-helper.c b/drivers/firmware/efi/efi-stub-helper.c index a168dd20511f..eb6d4be9e722 100644 --- a/drivers/firmware/efi/efi-stub-helper.c +++ b/drivers/firmware/efi/efi-stub-helper.c @@ -536,52 +536,99 @@ static efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg, } /* + * Get the number of UTF-8 bytes corresponding to an UTF-16 character. + * This overestimates for surrogates, but that is okay. + */ +static int efi_utf8_bytes(u16 c) +{ + return 1 + (c >= 0x80) + (c >= 0x800); +} + +/* + * 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. * Returns NULL on error. */ -static char *efi_convert_cmdline_to_ascii(efi_system_table_t *sys_table_arg, - efi_loaded_image_t *image, - int *cmd_line_len) +static char *efi_convert_cmdline(efi_system_table_t *sys_table_arg, + efi_loaded_image_t *image, + int *cmd_line_len) { - u16 *s2; + const u16 *s2; u8 *s1 = NULL; unsigned long cmdline_addr = 0; - int load_options_size = image->load_options_size / 2; /* ASCII */ - void *options = image->load_options; - int options_size = 0; + int load_options_chars = image->load_options_size / 2; /* UTF-16 */ + const u16 *options = image->load_options; + int options_bytes = 0; /* UTF-8 bytes */ + int options_chars = 0; /* UTF-16 chars */ efi_status_t status; - int i; u16 zero = 0; if (options) { s2 = options; - while (*s2 && *s2 != '\n' && options_size < load_options_size) { - s2++; - options_size++; + while (*s2 && *s2 != '\n' + && options_chars < load_options_chars) { + options_bytes += efi_utf8_bytes(*s2++); + options_chars++; } } - if (options_size == 0) { + if (!options_chars) { /* No command line options, so return empty string*/ - options_size = 1; options = &zero; } - options_size++; /* NUL termination */ + options_bytes++; /* NUL termination */ - status = efi_low_alloc(sys_table_arg, options_size, 0, &cmdline_addr); + status = efi_low_alloc(sys_table_arg, options_bytes, 0, &cmdline_addr); if (status != EFI_SUCCESS) return NULL; s1 = (u8 *)cmdline_addr; - s2 = (u16 *)options; - - for (i = 0; i < options_size - 1; i++) - *s1++ = *s2++; + s2 = (const u16 *)options; + s1 = efi_utf16_to_utf8(s1, s2, options_chars); *s1 = '\0'; - *cmd_line_len = options_size; + *cmd_line_len = options_bytes; return (char *)cmdline_addr; } |