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Author SHA1 Message Date
Arvind Sankar
6c4bcd8a46 efi/printf: Refactor code to consolidate padding and output
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: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-15-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:32:03 +02:00
Arvind Sankar
fb031937a8 efi/printf: Handle null string input
Print "(null)" for 's' if the input is a NULL pointer.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-14-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:31:50 +02:00
Arvind Sankar
dec6119952 efi/printf: Factor out integer argument retrieval
Factor out the code to get the correct type of numeric argument into a
helper function.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-13-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:31:50 +02:00
Arvind Sankar
3fbcf75bb4 efi/printf: Factor out width/precision parsing
Factor out the width/precision parsing into a helper function.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-12-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:31:48 +02:00
Arvind Sankar
7c30fd7916 efi/printf: Merge 'p' with the integer formats
Treat 'p' as a hexadecimal integer with precision equal to the number of
digits in void *.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-11-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:31:25 +02:00
Arvind Sankar
77e48db04a efi/printf: Fix minor bug in precision handling
A negative precision should be ignored completely, and the presence of a
valid precision should turn off the 0 flag.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-10-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:31:25 +02:00
Arvind Sankar
3b8350959c efi/printf: Factor out flags parsing and handle '%' earlier
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: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-9-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:31:25 +02:00
Arvind Sankar
ce5e3f909f efi/printf: Add 64-bit and 8-bit integer support
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: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-8-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:31:24 +02:00
Arvind Sankar
29a2806653 efi/printf: Drop %n format and L qualifier
%n is unused and deprecated.

The L qualifer is parsed but not actually implemented.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-7-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:30:52 +02:00
Arvind Sankar
bbf8e8b0fe efi/libstub: Optimize for size instead of speed
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: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-6-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:30:52 +02:00
Arvind Sankar
2c7d1e30e5 efi/libstub: Add a basic printf implementation
Copy vsprintf from arch/x86/boot/printf.c to get a simple printf
implementation.

Signed-off-by: Arvind 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: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 10:30:31 +02:00
Arvind Sankar
fd0528a249 efi/libstub: Buffer output of efi_puts
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: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-4-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 09:23:22 +02:00
Arvind Sankar
cb8c90a08c efi/libstub: Rename efi_[char16_]printk to efi_[char16_]puts
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: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-3-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 09:23:22 +02:00
Arvind Sankar
0b76735380 efi/libstub: Include dependencies of efistub.h
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: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-2-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-19 09:23:22 +02:00
Loïc Yhuel
b4f1874c62 tpm: check event log version before reading final events
This fixes the boot issues since 5.3 on several Dell models when the TPM
is enabled. Depending on the exact grub binary, booting the kernel would
freeze early, or just report an error parsing the final events log.

We get an event log in the SHA-1 format, which doesn't have a
tcg_efi_specid_event_head in the first event, and there is a final events
table which doesn't match the crypto agile format.
__calc_tpm2_event_size reads bad "count" and "efispecid->num_algs", and
either fails, or loops long enough for the machine to be appear frozen.

So we now only parse the final events table, which is per the spec always
supposed to be in the crypto agile format, when we got a event log in this
format.

Fixes: c46f340569 ("tpm: Reserve the TPM final events table")
Fixes: 166a2809d6 ("tpm: Don't duplicate events from the final event log in the TCG2 log")
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1779611
Signed-off-by: Loïc Yhuel <loic.yhuel@gmail.com>
Link: https://lore.kernel.org/r/20200512040113.277768-1-loic.yhuel@gmail.com
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Matthew Garrett <mjg59@google.com>
[ardb: warn when final events table is missing or in the wrong format]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-17 11:46:50 +02:00
Benjamin Thiel
e8da08a088 efi: Pull up arch-specific prototype efi_systab_show_arch()
Pull up arch-specific prototype efi_systab_show_arch() in order to
fix a -Wmissing-prototypes warning:

arch/x86/platform/efi/efi.c:957:7: warning: no previous prototype for
‘efi_systab_show_arch’ [-Wmissing-prototypes]
char *efi_systab_show_arch(char *str)

Signed-off-by: Benjamin Thiel <b.thiel@posteo.de>
Link: https://lore.kernel.org/r/20200516132647.14568-1-b.thiel@posteo.de
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-17 11:46:50 +02:00
Sami Tolvanen
cc49c71d2a efi/libstub: Disable Shadow Call Stack
Shadow stacks are not available in the EFI stub, filter out SCS flags.

Suggested-by: James Morse <james.morse@arm.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-15 16:35:50 +01:00
Punit Agrawal
3d8c11efd5 efi: cper: Add support for printing Firmware Error Record Reference
While debugging a boot failure, the following unknown error record was
seen in the boot logs.

    <...>
    BERT: Error records from previous boot:
    [Hardware Error]: event severity: fatal
    [Hardware Error]:  Error 0, type: fatal
    [Hardware Error]:   section type: unknown, 81212a96-09ed-4996-9471-8d729c8e69ed
    [Hardware Error]:   section length: 0x290
    [Hardware Error]:   00000000: 00000001 00000000 00000000 00020002  ................
    [Hardware Error]:   00000010: 00020002 0000001f 00000320 00000000  ........ .......
    [Hardware Error]:   00000020: 00000000 00000000 00000000 00000000  ................
    [Hardware Error]:   00000030: 00000000 00000000 00000000 00000000  ................
    <...>

On further investigation, it was found that the error record with
UUID (81212a96-09ed-4996-9471-8d729c8e69ed) has been defined in the
UEFI Specification at least since v2.4 and has recently had additional
fields defined in v2.7 Section N.2.10 Firmware Error Record Reference.

Add support for parsing and printing the defined fields to give users
a chance to figure out what went wrong.

Signed-off-by: Punit Agrawal <punit1.agrawal@toshiba.co.jp>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: linux-acpi@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Link: https://lore.kernel.org/r/20200512045502.3810339-1-punit1.agrawal@toshiba.co.jp
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-14 11:11:20 +02:00
Lenny Szubowicz
fd62619598 efi/libstub/x86: Avoid EFI map buffer alloc in allocate_e820()
In allocate_e820(), call the EFI get_memory_map() service directly
instead of indirectly via efi_get_memory_map(). This avoids allocation
of a buffer and return of the full EFI memory map, which is not needed
here and would otherwise need to be freed.

Routine allocate_e820() only needs to know how many EFI memory
descriptors there are in the map to allocate an adequately sized
e820ext buffer, if it's needed. Note that since efi_get_memory_map()
returns a memory map buffer sized with extra headroom, allocate_e820()
now needs to explicitly factor that into the e820ext size calculation.

Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-14 11:11:18 +02:00
Dave Young
8f592ada59 efi/earlycon: Fix early printk for wider fonts
When I play with terminus fonts I noticed the efi early printk does
not work because the earlycon code assumes font width is 8.

Here add the code to adapt with larger fonts.  Tested with all kinds
of kernel built-in fonts on my laptop. Also tested with a local draft
patch for 14x28 !bold terminus font.

Signed-off-by: Dave Young <dyoung@redhat.com>
Link: https://lore.kernel.org/r/20200412024927.GA6884@dhcp-128-65.nay.redhat.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-12 12:29:45 +02:00
Linus Torvalds
e99332e7b4 gcc-10: mark more functions __init to avoid section mismatch warnings
It seems that for whatever reason, gcc-10 ends up not inlining a couple
of functions that used to be inlined before.  Even if they only have one
single callsite - it looks like gcc may have decided that the code was
unlikely, and not worth inlining.

The code generation difference is harmless, but caused a few new section
mismatch errors, since the (now no longer inlined) function wasn't in
the __init section, but called other init functions:

   Section mismatch in reference from the function kexec_free_initrd() to the function .init.text:free_initrd_mem()
   Section mismatch in reference from the function tpm2_calc_event_log_size() to the function .init.text:early_memremap()
   Section mismatch in reference from the function tpm2_calc_event_log_size() to the function .init.text:early_memunmap()

So add the appropriate __init annotation to make modpost not complain.
In both cases there were trivially just a single callsite from another
__init function.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-09 17:50:03 -07:00
Joe Perches
4026229934 efi/libstub: Correct comment typos
Fix a couple typos in comments.

Signed-off-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/ec53e67b3ac928922807db3cb1585e911971dadc.1588273612.git.joe@perches.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-06 11:27:55 +02:00
Ard Biesheuvel
0b8d9fc995 efi/libstub: Make efi_printk() input argument const char*
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: Joe Perches <joe@perches.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-05 10:27:18 +02:00
Ard Biesheuvel
f77767ed5f efi/libstub/x86: Work around LLVM ELF quirk build regression
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: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Fangrui Song <maskray@google.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-05 09:28:39 +02:00
Arvind Sankar
de8c55208c efi/libstub: Fix mixed mode boot issue after macro refactor
Commit

  22090f84bc ("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: 22090f84bc ("efi/libstub: unify EFI call wrappers for non-x86")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200504150248.62482-1-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-05 09:25:39 +02:00
Arvind Sankar
055042bedd efi/libstub: Check return value of efi_parse_options
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: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-12-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Arvind Sankar
7dde67f2a2 efi/x86: Support builtin command line
Add support for the x86 CMDLINE_BOOL and CMDLINE_OVERRIDE configuration
options.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-11-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Arvind Sankar
f61900fd0e efi/libstub: Unify initrd loading across architectures
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: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-10-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Arvind Sankar
987053a300 efi/x86: Move command-line initrd loading to efi_main
Consolidate the initrd loading in efi_main.

The command line options now need to be parsed only once.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-9-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Arvind Sankar
3839ab85d0 efi/libstub: Upgrade ignored dtb= argument message to error
Use efi_err if we ignore a command-line dtb= argument, so that it shows
up even on a quiet boot.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-8-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Arvind Sankar
dad5b32421 efi/tpm: Use efi_err for error messages
Use efi_err instead of bare efi_printk for error messages.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-7-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Arvind Sankar
61eac6d92d efi/gop: Use efi_err for error messages
Use efi_err instead of bare efi_printk for error messages.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-6-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Arvind Sankar
36bdd0a78d efi/x86: Use efi_err for error messages
Use efi_err instead of bare efi_printk for error messages.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-5-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Arvind Sankar
793473c28a efi/libstub: Move pr_efi/pr_efi_err into efi namespace
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: Joe Perches <joe@perches.com>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-4-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Arvind Sankar
eed4e0193e efi/libstub: Add a helper function to split 64-bit values
In several places 64-bit values need to be split up into two 32-bit
fields, in order to be backward-compatible with the old 32-bit ABIs.

Instead of open-coding this, add a helper function to set a 64-bit value
as two 32-bit fields.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-3-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Arvind Sankar
019512f1fd efi/x86: Use correct size for boot_params
struct boot_params is only 4096 bytes, not 16384. Fix this by using
sizeof(struct boot_params) instead of hardcoding the incorrect value.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-2-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-01 09:40:02 +02:00
Heinrich Schuchardt
081d515084 efi/libstub: Avoid returning uninitialized data from setup_graphics()
Currently, setup_graphics() ignores the return value of efi_setup_gop(). As
AllocatePool() does not zero out memory, the screen information table will
contain uninitialized data in this case.

We should free the screen information table if efi_setup_gop() returns an
error code.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Link: https://lore.kernel.org/r/20200426194946.112768-1-xypron.glpk@gmx.de
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-30 23:26:30 +02:00
Ard Biesheuvel
4da0b2b7e6 efi/libstub: Re-enable command line initrd loading for x86
Commit:

  cf6b836648 ("efi/libstub: Make initrd file loader configurable")

inadvertently disabled support on x86 for loading an initrd passed via
the initrd= option on the kernel command line.

Add X86 to the newly introduced Kconfig option's title and depends
declarations, so it gets enabled by default, as before.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: linux-efi@vger.kernel.org
2020-04-25 12:26:32 +02:00
Ard Biesheuvel
4eb8320bd1 efi: Move arch_tables check to caller
Instead of making match_config_table() test its table_types pointer for
NULL-ness, omit the call entirely if no arch_tables pointer was provided
to efi_config_parse_tables().

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Ard Biesheuvel
4e9a0f73f0 efi: Clean up config table description arrays
Increase legibility by adding whitespace to the efi_config_table_type_t
arrays that describe which EFI config tables we look for when going over
the firmware provided list. While at it, replace the 'name' char pointer
with a char array, which is more space efficient on relocatable 64-bit
kernels, as it avoids a 8 byte pointer and the associated relocation
data (24 bytes when using RELA format)

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Ard Biesheuvel
0a75561489 efi/libstub/x86: Avoid getter function for efi_is64
We no longer need to take special care when using global variables
in the EFI stub, so switch to a simple symbol reference for efi_is64.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Ard Biesheuvel
980771f616 efi/libstub: Drop __pure getters for EFI stub options
The practice of using __pure getter functions to access global
variables in the EFI stub dates back to the time when we had to
carefully prevent GOT entries from being emitted, because we
could not rely on the toolchain to do this for us.

Today, we use the hidden visibility pragma for all EFI stub source
files, which now all live in the same subdirectory, and we apply a
sanity check on the objects, so we can get rid of these getter
functions and simply refer to global data objects directly.

So switch over the remaining boolean variables carrying options set
on the kernel command line.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Ard Biesheuvel
ccc27ae774 efi/libstub: Drop __pure getter for efi_system_table
The practice of using __pure getter functions to access global
variables in the EFI stub dates back to the time when we had to
carefully prevent GOT entries from being emitted, because we
could not rely on the toolchain to do this for us.

Today, we use the hidden visibility pragma for all EFI stub source
files, which now all live in the same subdirectory, and we apply a
sanity check on the objects, so we can get rid of these getter
functions and simply refer to global data objects directly.

Start with efi_system_table(), and convert it into a global variable.
While at it, make it a pointer-to-const, because we can.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Arvind Sankar
544393707f efi: Kill __efistub_global
Now that both arm and x86 are using the linker script to place the EFI
stub's global variables in the correct section, remove __efistub_global.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20200416151227.3360778-4-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Arvind Sankar
26a92425f9 efi/x86: Remove __efistub_global and add relocation check
Instead of using __efistub_global to force variables into the .data
section, leave them in the .bss but pull the EFI stub's .bss section
into .data in the linker script for the compressed kernel.

Add relocation checking for x86 as well to catch non-PC-relative
relocations that require runtime processing, since the EFI stub does not
do any runtime relocation processing.

This will catch, for example, data relocations created by static
initializers of pointers.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200416151227.3360778-3-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Arvind Sankar
420b6d00ca efi/arm: Remove __efistub_global annotation
Instead of using __efistub_global to force variables into the .data
section, leave them in the .bss but pull the EFI stub's .bss section
into .data in the linker script for the compressed kernel.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20200416151227.3360778-2-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Ard Biesheuvel
685d8164b5 efi/libstub: Move efi_relocate_kernel() into separate source file
Move efi_relocate_kernel() into a separate source file, so that it
only gets pulled into builds for architectures that use it. Since
efi_relocate_kernel() is the only user of efi_low_alloc(), let's
move that over as well.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Ard Biesheuvel
e71356fe29 efi/libstub/arm64: Switch to ordinary page allocator for kernel image
It is no longer necessary to locate the kernel as low as possible in
physical memory, and so we can switch from efi_low_alloc() [which is
a rather nasty concoction on top of GetMemoryMap()] to a new helper
called efi_allocate_pages_aligned(), which simply rounds up the size
to account for the alignment, and frees the misaligned pages again.

So considering that the kernel can live anywhere in the physical
address space, as long as its alignment requirements are met, let's
switch to efi_allocate_pages_aligned() to allocate the pages.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Ard Biesheuvel
43b1df0e01 efi/libstub: Add API function to allocate aligned memory
Break out the code to create an aligned page allocation from mem.c
and move it into a function efi_allocate_pages_aligned() in alignedmem.c.
Update efi_allocate_pages() to invoke it unless the minimum alignment
equals the EFI page size (4 KB), in which case the ordinary page
allocator is sufficient. This way, efi_allocate_pages_aligned() will
only be pulled into the build if it is actually being used (which will
be on arm64 only in the immediate future)

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24 14:52:16 +02:00
Ard Biesheuvel
5d12da9dd6 efi/libstub/arm64: Simplify randomized loading of kernel image
The KASLR code path in the arm64 version of the EFI stub incorporates
some overly complicated logic to randomly allocate a region of the right
alignment: there is no need to randomize the placement of the kernel
modulo 2 MiB separately from the placement of the 2 MiB aligned allocation
itself - we can simply follow the same logic used by the non-randomized
placement, which is to allocate at the correct alignment, and only take
TEXT_OFFSET into account if it is not a round multiple of the alignment.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-23 20:15:06 +02:00