The documentation provided by kobject_init_and_add() clearly spells out
the need to call kobject_put() on the kobject if an error is returned.
Add this missing call to the error path.

Cc: <stable@vger.kernel.org>
Reported-by: N亿一 <teroincn@gmail.com>
Signed-off-by: NArd Biesheuvel <ardb@kernel.org>

Now that we removed the memory limit for the allocation of the
command line, there is no longer a need to use the page based
allocator so switch to a pool allocation instead.
Signed-off-by: NArd Biesheuvel <ardb@kernel.org>

Check if the command line passed in is larger than COMMAND_LINE_SIZE,
and truncate it to the last full argument if so.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200521002921.69650-1-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Now we can use snprintf to do the UTF-16 to UTF-8 translation for the
command line.

Drop the special "zero" trick to handle an empty command line. This was
unnecessary even before this since with options_chars == 0,
efi_utf16_to_utf8 would not have accessed options at all. snprintf won't
access it either with a precision of 0.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-25-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

efi_convert_cmdline currently overestimates the length of the equivalent
UTF-8 encoding.

snprintf can now be used to do the conversion to UTF-8, however, it does
not have a way to specify the size of the UTF-16 string, only the size
of the resulting UTF-8 string. So in order to use it, we need to
precalculate the exact UTF-8 size.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-24-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

efi_printk can now handle the UTF-16 filename, so print it using efi_err
instead of a separate efi_char16_puts call.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-23-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

In order to be able to use the UTF-16 support added to vsprintf in the
previous commit, enhance efi_puts to decode UTF-8 into UTF-16. Invalid
UTF-8 encodings are passed through unchanged.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-22-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Support %lc and %ls to output UTF-16 strings (converted to UTF-8).
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-21-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Add video=efifb:list option to list the modes that are available.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-20-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Add the required typedefs etc for using con_in's simple text input
protocol, and for using the boottime event services.

Also add the prototype for the "stall" boot service.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-19-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Use the efi_printk function in efi_info/efi_err, and add efi_debug. This
allows formatted output at different log levels.

Add the notion of a loglevel instead of just quiet/not-quiet, and
parse the efi=debug kernel parameter in addition to quiet.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200520170223.GA3333632@rani.riverdale.lan/Signed-off-by: NArd Biesheuvel <ardb@kernel.org>

Implement vsnprintf instead of vsprintf to avoid the possibility of a
buffer overflow.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-17-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

If we get an invalid conversion specifier, bail out instead of trying to
fix it up. The format string likely has a typo or assumed we support
something that we don't, in either case the remaining arguments won't
match up with the remaining format string.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-16-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Consolidate the actual output of the formatted text into one place.

Fix a couple of edge cases:
1. If 0 is printed with a precision of 0, the printf specification says
   that nothing should be output, with one exception (2b).
2. The specification for octal alternate format (%#o) adds the leading
   zero not as a prefix as the 0x for hexadecimal is, but by increasing
   the precision if necessary to add the zero. This means that
   a. %#.2o turns 8 into "010", but 1 into "01" rather than "001".
   b. %#.o prints 0 as "0" rather than "", unlike the situation for
      decimal, hexadecimal and regular octal format, which all output an
      empty string.

Reduce the space allocated for printing a number to the maximum actually
required (22 bytes for a 64-bit number in octal), instead of the 66
bytes previously allocated.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-15-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Print "(null)" for 's' if the input is a NULL pointer.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-14-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Factor out the code to get the correct type of numeric argument into a
helper function.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-13-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Factor out the width/precision parsing into a helper function.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-12-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Treat 'p' as a hexadecimal integer with precision equal to the number of
digits in void *.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-11-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

A negative precision should be ignored completely, and the presence of a
valid precision should turn off the 0 flag.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-10-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Move flags parsing code out into a helper function.

The '%%' case can be handled up front: it is not allowed to have flags,
width etc.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-9-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Support 'll' qualifier for long long by copying the decimal printing
code from lib/vsprintf.c. For simplicity, the 32-bit code is used on
64-bit architectures as well.

Support 'hh' qualifier for signed/unsigned char type integers.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-8-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

%n is unused and deprecated.

The L qualifer is parsed but not actually implemented.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-7-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Reclaim the bloat from the addition of printf by optimizing the stub for
size. With gcc 9, the text size of the stub is:

ARCH    before  +printf    -Os
arm      35197    37889  34638
arm64    34883    38159  34479
i386     18571    21657  17025
x86_64   25677    29328  22144
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-6-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Copy vsprintf from arch/x86/boot/printf.c to get a simple printf
implementation.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-5-nivedita@alum.mit.edu
[ardb: add some missing braces in if...else clauses]
Signed-off-by: NArd Biesheuvel <ardb@kernel.org>

Use a buffer to convert the string to UTF-16. This will reduce the
number of firmware calls required to print the string from one per
character to one per string in most cases.

Cast the input char to unsigned char before converting to efi_char16_t
to avoid sign-extension in case there are any non-ASCII characters in
the input.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-4-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

These functions do not support formatting, unlike printk. Rename them to
puts to make that clear.

Move the implementations of these two functions next to each other.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-3-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Add #include directives for include files that efistub.h depends on,
instead of relying on them having been included by the C source files
prior to efistub.h.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-2-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Fix a couple typos in comments.
Signed-off-by: NJoe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/ec53e67b3ac928922807db3cb1585e911971dadc.1588273612.git.joe@perches.comSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

To help the compiler figure out that efi_printk() will not modify
the string it is given, make the input argument type const char*.

While at it, simplify the implementation as well.
Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NArd Biesheuvel <ardb@kernel.org>

When building the x86 EFI stub with Clang, the libstub Makefile rules
that manipulate the ELF object files may throw an error like:

    STUBCPY drivers/firmware/efi/libstub/efi-stub-helper.stub.o
  strip: drivers/firmware/efi/libstub/efi-stub-helper.stub.o: Failed to find link section for section 10
  objcopy: drivers/firmware/efi/libstub/efi-stub-helper.stub.o: Failed to find link section for section 10

This is the result of a LLVM feature [0] where symbol references are
stored in a LLVM specific .llvm_addrsig section in a non-transparent way,
causing generic ELF tools such as strip or objcopy to choke on them.

So force the compiler not to emit these sections, by passing the
appropriate command line option.

[0] https://sourceware.org/bugzilla/show_bug.cgi?id=23817

Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Reported-by: NArnd Bergmann <arnd@arndb.de>
Suggested-by: NFangrui Song <maskray@google.com>
Signed-off-by: NArd Biesheuvel <ardb@kernel.org>

Commit

  22090f84 ("efi/libstub: unify EFI call wrappers for non-x86")

refactored the macros that are used to provide wrappers for mixed-mode
calls on x86, allowing us to boot a 64-bit kernel on 32-bit firmware.

Unfortunately, this broke mixed mode boot due to the fact that
efi_is_native() is not a macro on x86.

All of these macros should go together, so rather than testing each one
to see if it is defined, condition the generic macro definitions on a
new ARCH_HAS_EFISTUB_WRAPPERS, and remove the wrapper definitions on x86
as well if CONFIG_EFI_MIXED is not enabled.

Fixes: 22090f84 ("efi/libstub: unify EFI call wrappers for non-x86")
Reported-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200504150248.62482-1-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

efi_parse_options can fail if it is unable to allocate space for a copy
of the command line. Check the return value to make sure it succeeded.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-12-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Add support for the x86 CMDLINE_BOOL and CMDLINE_OVERRIDE configuration
options.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-11-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Factor out the initrd loading into a common function that can be called
both from the generic efi-stub.c and the x86-specific x86-stub.c.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-10-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Consolidate the initrd loading in efi_main.

The command line options now need to be parsed only once.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-9-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Use efi_err if we ignore a command-line dtb= argument, so that it shows
up even on a quiet boot.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-8-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Use efi_err instead of bare efi_printk for error messages.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-7-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Use efi_err instead of bare efi_printk for error messages.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-6-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Use efi_err instead of bare efi_printk for error messages.
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-5-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>

Rename pr_efi to efi_info and pr_efi_err to efi_err to make it more
obvious that they are part of the EFI stub and not generic printk infra.
Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NArvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-4-nivedita@alum.mit.eduSigned-off-by: NArd Biesheuvel <ardb@kernel.org>