10614 Commits

Author SHA1 Message Date
Benjamin Herrenschmidt
55604aaad2 acpi: Add SPCR and generic address definitions
This adds the definition of the two ACPI tables according to the spec.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-18 23:08:22 +01:00
Benjamin Herrenschmidt
cff78b3b61 kern/acpi: Export a generic grub_acpi_find_table()
And convert grub_acpi_find_fadt() to use it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-18 23:07:06 +01:00
Maxim Fomin
1a241e0506 kern/fs: Fix possible integer overflow in i386-pc mode with large partitions
The i386-pc mode supports MBR partition scheme where maximum partition
size is 2 TiB. In case of large partitions left shift expression with
unsigned long int "length" object may cause integer overflow making
calculated partition size less than true value. This issue is fixed by
increasing the size of "length" integer type.

Signed-off-by: Maxim Fomin <maxim@fomin.one>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 16:37:11 +01:00
Glenn Washburn
4ba977777c commands/cmp: Only return success when both files have the same contents
This allows the cmp command to be used in GRUB scripts to conditionally
run commands based on whether two files are the same.

The command is now quiet by default and the -v switch can be given to enable
verbose mode, the previous behavior.

Update documentation accordingly.

Suggested-by: Li Gen <ligenlive@gmail.com>
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 16:32:42 +01:00
Glenn Washburn
004ffa68ae docs: Remove text about cryptodisk UUIDs no being able to use dashes
This was fixed here: 3cf2e848bc (disk/cryptodisk: Allows UUIDs to be compared
in a dash-insensitive manner).

Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 16:29:03 +01:00
Glenn Washburn
bac1cbd3d1 tests/util/grub-shell: Add GRUB output logfile with grub-shell --debug
This allows seeing full QEMU output of grub-shell, which can be invaluable
when debugging failing tests.

Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 16:25:15 +01:00
Marek Marczykowski-Górecki
f601d9f3f7 templates/linux_xen: Fix detecting XSM policy
The xenpolicy variable was left set from previous function call. This
resulted in all-but-first menu entries including XSM policy, even if it
did not exist.

Fix this by initializing the xenpolicy variable.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 16:15:15 +01:00
Zhang Boyang
faca60df76 font: Reject fonts with negative max_char_width or max_char_height
If max_char_width or max_char_height are negative wrong values can be propagated
by grub_font_get_max_char_width() or grub_font_get_max_char_height(). Prevent
this from happening.

Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 16:06:03 +01:00
Zhang Boyang
f680696647 font: Assign null_font to unknown_glyph
Like glyphs in ascii_font_glyph[], assign null_font to
unknown_glyph->font in order to prevent grub_font_get_*() from
dereferencing NULL pointer.

Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 16:01:18 +01:00
Zhang Boyang
d7ed2ebcd6 font: Check return value of grub_malloc() in ascii_glyph_lookup()
There is a problem in ascii_glyph_lookup(). It doesn't check the return
value of grub_malloc(). If memory can't be allocated, then NULL pointer
will be written to.

This patch fixes the problem by fallbacking to unknown_glyph when
grub_malloc() returns NULL.

Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 16:01:01 +01:00
Maxim Fomin
5464e31a4e disk/plainmount: Support plain encryption mode
This patch adds support for plain encryption mode, plain dm-crypt, via
new module/command named "plainmount".

Signed-off-by: Maxim Fomin <maxim@fomin.one>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Glenn Washburn <development@efficientek.com>
2023-01-10 15:59:51 +01:00
Pete Batard
b7ec14c886 util/grub-mkrescue: Search by file UUID rather than partition UUID for EFI boot
The final piece needed to add UEFI file system transposition support is to
ensure the boot media can be located regardless of how the boot partition
was instantiated. Especially, we do not want to be reliant on brittle
partition UUIDs, as these only work if a boot media is duplicated at the
block level and not at the file system level.

To accomplish this for EFI boot, we now create a UUID file in a .disk/
directory, that can then be searched for.

Note: The switch from make_image_fwdisk_abs() to make_image_abs() is
needed in order to use the search functionality.

Signed-off-by: Pete Batard <pete@akeo.ie>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 15:45:57 +01:00
Pete Batard
a41fafd3ce util/grub-mkrescue: Preserve a copy of the EFI bootloaders on the ISO 9660 file system
To enable file system transposition support for UEFI, we also must ensure that
there exists a copy of the EFI bootloaders, that are currently embedded in the
efi.img for xorriso, at their expected UEFI location on the ISO 9660 file system.

This is accomplished by removing the use of a temporary directory to create the
efi/ content, to instead place it at the root of the ISO 9660 content.

Signed-off-by: Pete Batard <pete@akeo.ie>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 15:43:12 +01:00
Pete Batard
c567d89660 util/grub-mkrescue: Add support for FAT and NTFS on EFI boot
In order to add file system transposition support for UEFI, i.e. the ability
to copy the content of an grub-mkrescue ISO 9660 image onto user-formatted
media, and have that boot on UEFI systems, the first thing we need to do is
add support for the file systems that are natively handled by UEFI. This
mandatorily includes FAT, but we also include NTFS as the latter is also
commonly supported on modern x64 platforms.

Signed-off-by: Pete Batard <pete@akeo.ie>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2023-01-10 14:08:25 +01:00
t.feng
7259d55ffc util/bash-completion: Disable SC2120 shellcheck warning
SC2120 (warning): function references arguments, but none are ever passed.

In grub-completion.bash.in line 63:
__grub_get_options_from_help () {
^-- SC2120 (warning)
     local prog

     if [ $# -ge 1 ]; then
         prog="$1"

The arg of __grub_get_options_from_help() is optional. So, the current
code meets the exception and does not need to be modified. Ignoring the
warning then.

More: https://github.com/koalaman/shellcheck/wiki/SC2120

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:27 +01:00
t.feng
e9802fbdeb util/bash-completion: Fix SC2155 shellcheck warning
SC2155 (warning): Declare and assign separately to avoid masking return values.

The exit status of the command is overridden by the exit status of the
creation of the local variable.

In grub-completion.bash.in line 115:
    local config_file=$(__grub_dir)/grub.cfg
          ^---------^ SC2155 (warning)

In grub-completion.bash.in line 126:
    local grub_dir=$(__grub_dir)
          ^------^ SC2155 (warning)

More: https://github.com/koalaman/shellcheck/wiki/SC2155

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:27 +01:00
t.feng
61e4f408b0 util/bash-completion: Fix SC2207 shellcheck warning
SC2207 (warning): Prefer mapfile or read -a to split
command output (or quote to avoid splitting).

In grub-completion.bash.in line 56:
        COMPREPLY=($(compgen -P "${2-}" -W "${1-}" -S "${4-}" -- "$cur"))
                   ^-- SC2207 (warning)

In grub-completion.bash.in line 119:
        COMPREPLY=( $(compgen \
                    ^-- SC2207 (warning)

In grub-completion.bash.in line 128:
    COMPREPLY=( $( compgen -f -X '!*/*.mod' -- "${grub_dir}/$cur" | {
                ^-- SC2207 (warning)

COMPREPLY=($(command)) are doing unquoted command expansion in an array.
This will invoke the shell's sloppy word splitting and glob expansion.

If we want to split the output into lines or words, use read -r and
loops will be better. This prevents the shell from doing unwanted
splitting and glob expansion, and therefore avoiding problems with
output containing spaces or special characters.

More: https://github.com/koalaman/shellcheck/wiki/SC2207

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:27 +01:00
t.feng
2029c4822b util/bash-completion: Fix SC2070 shellcheck error
SC2070 (error): -n doesn't work with unquoted arguments.
Quote or use [[ ]].
In grub-completion.bash.in line 130:
             [ -n $tmp ] && {
                  ^--^ SC2070 (error)

More: https://github.com/koalaman/shellcheck/wiki/SC2070

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
Steve McIntyre
e375394fb9 kern/file: Fix error handling in grub_file_open()
grub_file_open() calls grub_file_get_device_name(), but doesn't check
the return. Instead, it checks if grub_errno is set.

However, nothing initialises grub_errno here when grub_file_open()
starts. This means that trying to open one file that doesn't exist and
then trying to open another file that does will (incorrectly) also
fail to open that second file.

Let's fix that.

Signed-off-by: Steve McIntyre <steve@einval.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
Jeremy Szu
012fe7f055 loader/i386/linux: Fix initrd maximum address overflow
The current i386 initrd is limited under 1 GiB memory and it works with
most compressed initrds (also initrd_addr_max case reported by kernel).

addr = (addr_max - aligned_size) & ~0xFFF;

Above line is used to calculate the reasonable address to store the initrd.

However, if initrd size is greater than 1 GiB or initrd_addr_max, then it
will get overflow, especially on x86_64 arch.

Therefore, add a check point to prevent it overflows as well as having
a debug log for complex story of initrd addresses.

Signed-off-by: Jeremy Szu <jeremy.szu@canonical.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
Dimitri John Ledkov
ef562269bc templates: Enable fwsetup on EFI platforms only
Only perform call to fwsetup if one is on EFI platform. On all other
platforms fwsetup command does not exists, and thus returns 0 and
a useless uefi-firmware menu entry gets generated.

Signed-off-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
t.feng
2e32d23574 fs/xfs: Fix memory leaks in XFS module
Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
t.feng
98ae234000 fs/squash4: Fix memory leaks in grub_squash_iterate_dir()
Fixes: 20dd511c8 (Handle "." and ".." on squashfs)

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
t.feng
7338cbe91a fs/iso9660: Fix memory leaks in grub_iso9660_susp_iterate()
Fixes: 99373ce47 (* grub-core/fs/iso9660.c: Remove nested functions)

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Thomas Schmitt <scdbackup@gmx.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
t.feng
a1e05167c8 fs/hfsplus: Fix memory leak in grub_hfsplus_btree_search()
Fixes: 58ea11d5b (fs/hfsplus: Don't fetch a key beyond the end of the node)

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
t.feng
6cdd08b362 fs/bfs: Fix memory leak in read_bfs_file()
The l1_entries and l2_entries were not freed at the end of file read.

Fixes: 5825b3794 (BFS implementation based on the specification)

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
t.feng
a2f7914c3c fs/ntfs: Fix memory leaks in grub_ntfs_read_symlink()
Fixes: 5773fb641 (Support NTFS reparse points)

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
t.feng
f3fab3ea60 fs/minix: Fix memory leaks in grub_minix_lookup_symlink()
Fixes: a07e6ad01 (* grub-core/fs/minix.c: Remove variable length arrays)

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:26 +01:00
t.feng
3b49391bc5 fs/btrfs: Fix memory leak in find_path()
Fixes: 82591fa6e (Make / in btrfs refer to real root)

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:25 +01:00
t.feng
022365aeaa fs/affs: Fix memory leaks in grub_affs_create_node()
The hashtable is not freed if GRUB_AFFS_FILETYPE_HARDLINK and
grub_disk_read() failed. If grub_affs_create_node() returns non-zero
the hashtable should be freed too.

By the way, the hashtable argument is unused in grub_affs_create_node().
So, we can remove the argument and free it in grub_affs_iterate_dir().
It allocates the memory and it should be responsible for releasing it.

This is why commit ebf32bc4e9 (fs/affs: Fix resource leaks) missed
this memory leak.

Fixes: ebf32bc4e9 (fs/affs: Fix resource leaks)

Signed-off-by: t.feng <fengtao40@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:25 +01:00
Ryan Cohen
77afd25f80 normal/cmdline: Fix two related integer underflows
An unchecked decrement operation in cl_print() would cause a few
integers to underflow. Where an output terminal's state is stored in
cl_term, the values cl_term->ystart and cl_term->pos.y both underflow.

This can be replicated with the following steps:

1. Get to the GRUB command line
2. Hold down the "d" key (or any key that enters a visible character)
   until it fills the entire row
3. Press "HOME" and then press "CTRL-k". This will clear every
   character entered in step 2
4. Continuously press "CTRL-y" until the terminal scrolls the original
   prompt ("grub> ") passed the terminal's top row. Now, no prompt
   should be visible. This step causes cl_term->ystart to underflow
5. Press "HOME" and then "d" (or any visible character). This can have
   different visual effects for different systems, but it will always
   cause cl_term->pos.y to underflow

On BIOS systems, these underflows cause the output terminal to
completely stop displaying anything. Characters can still be
entered and commands can be run, but nothing will display on the
terminal. From here, you can only get the display working by running
a command to switch the current output terminal to a different type:

terminal_output <OTHER_TERMINAL>

On UEFI systems, these replication steps do not break the output
terminal. Until you press "ENTER", the cursor stops responding to input,
but you can press "ENTER" after step 5 and the command line will
work properly again. This patch is mostly important for BIOS systems
where the output terminal is rendered unusable after the underflows
occur.

This patch adds two checks, one for each variable. It ensures that
cl_term->ystart does not decrement passed 0. It also ensures that
cl_term->pos.y does not get set passed the terminal's bottom row.

When the previously listed replication steps are followed with this
patch, the terminal's cursor will be set to the top row and the command
line is still usable, even on BIOS systems.

Signed-off-by: Ryan Cohen <rcohenprogramming@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:25 +01:00
Ryan Cohen
108a3865f4 term/i386/pc/vga_text: Prevent out-of-bounds writes to VGA text buffer
Coordinates passed to screen_write_char() did not have any checks to
ensure they are not out-of-bounds. This adds an if statement to prevent
out-of-bounds writes to the VGA text buffer.

Signed-off-by: Ryan Cohen <rcohenprogramming@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:25 +01:00
Gary Lin
544fd63f0f loader/linux: Ensure the newc pathname is NULL-terminated
Per "man 5 cpio", the namesize in the cpio header includes the trailing
NUL byte of the pathname and the pathname is followed by NUL bytes, but
the current implementation ignores the trailing NUL byte when making
the newc header. Although make_header() tries to pad the pathname string,
the padding won't happen when strlen(name) + sizeof(struct newc_head)
is a multiple of 4, and the non-NULL-terminated pathname may lead to
unexpected results.

Assume that a file is created with 'echo -n aaaa > /boot/test12' and
loaded by grub2:

    linux /boot/vmlinuz
    initrd newc:test12:/boot/test12 /boot/initrd

The initrd command eventually invoked grub_initrd_load() and sent
't''e''s''t''1''2' to make_header() to generate the header:

00000070  30 37 30 37 30 31 33 30  31 43 41 30 44 45 30 30  |070701301CA0DE00|
00000080  30 30 38 31 41 34 30 30  30 30 30 33 45 38 30 30  |0081A4000003E800|
00000090  30 30 30 30 36 34 30 30  30 30 30 30 30 31 36 33  |0000640000000163|
000000a0  37 36 45 34 35 32 30 30  30 30 30 30 30 34 30 30  |76E4520000000400|
000000b0  30 30 30 30 30 38 30 30  30 30 30 30 31 33 30 30  |0000080000001300|
000000c0  30 30 30 30 30 30 30 30  30 30 30 30 30 30 30 30  |0000000000000000|
000000d0  30 30 30 30 30 36 30 30  30 30 30 30 30 30 74 65  |00000600000000te|
                                                                  ^namesize
000000e0  73 74 31 32 61 61 61 61  30 37 30 37 30 31 30 30  |st12aaaa07070100|
                   ^^ end of the pathname

Since strlen("test12") + sizeof(struct newc_head) is 116 = 29 * 4,
make_header() didn't pad the pathname, and the file content followed
"test12" immediately. This violates the cpio format and may trigger such
error during linux boot:

    Initramfs unpacking failed: ZSTD-compressed data is trunc

To avoid the potential problems, this commit counts the trailing NUL byte
in when calling make_header() and adjusts the initrd size accordingly.

Now the header becomes

00000070  30 37 30 37 30 31 33 30  31 43 41 30 44 45 30 30  |070701301CA0DE00|
00000080  30 30 38 31 41 34 30 30  30 30 30 33 45 38 30 30  |0081A4000003E800|
00000090  30 30 30 30 36 34 30 30  30 30 30 30 30 31 36 33  |0000640000000163|
000000a0  37 36 45 34 35 32 30 30  30 30 30 30 30 34 30 30  |76E4520000000400|
000000b0  30 30 30 30 30 38 30 30  30 30 30 30 31 33 30 30  |0000080000001300|
000000c0  30 30 30 30 30 30 30 30  30 30 30 30 30 30 30 30  |0000000000000000|
000000d0  30 30 30 30 30 37 30 30  30 30 30 30 30 30 74 65  |00000700000000te|
                                                                  ^namesize
000000e0  73 74 31 32 00 00 00 00  61 61 61 61 30 37 30 37  |st12....aaaa0707|
                      ^^ end of the pathname

Besides the trailing NUL byte, make_header() pads 3 more NUL bytes, and
the user can safely read the pathname without a further check.

To conform to the cpio format, the headers for "TRAILER!!!" are also
adjusted to include the trailing NUL byte, not ignore it.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:25 +01:00
Jagannathan Raman
c08edc545c fs/udf: Validate length of AED in grub_udf_read_block()
Validate the length of Allocation Extent Descriptor in grub_udf_read_block(),
based on the details in UDF spec. v2.01 section 2.3.11.

Fixes: CID 314037

Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:38:25 +01:00
Ismael Luceno
67e90bf743 util/grub-install: Ensure a functional /dev/nvram
This enables an early failure; for i386-ieee1275 and powerpc-ieee1275 on
Linux, without /dev/nvram the system may be left in an unbootable state.

Signed-off-by: Ismael Luceno <iluceno@suse.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 23:37:32 +01:00
Ismael Luceno
fc8768bdc3 templates: Set defaults using var substitution
Signed-off-by: Ismael Luceno <iluceno@suse.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 14:47:11 +01:00
Glenn Washburn
85961bd92a tests: Put all generated files into working dir and use better file names
When running tests there are many invocations of grub-shell, and because
the output files are all random names in the same tmp directory, it
becomes more work to figure out which files went with which grub-shell
invocations. So all generated files from one invocation of grub-shell
are put into a randomly named directory, so as not to collide with other
grub-shell invocations. And now that the generated files can be put in
a location where they will not get stepped on, and they can be named
sensible names.

Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-12-07 14:46:51 +01:00
Zhang Boyang
1514678888 normal/charset: Fix an integer overflow in grub_unicode_aglomerate_comb()
The out->ncomb is a bit-field of 8 bits. So, the max possible value is 255.
However, code in grub_unicode_aglomerate_comb() doesn't check for an
overflow when incrementing out->ncomb. If out->ncomb is already 255,
after incrementing it will get 0 instead of 256, and cause illegal
memory access in subsequent processing.

This patch introduces GRUB_UNICODE_NCOMB_MAX to represent the max
acceptable value of ncomb. The code now checks for this limit and
ignores additional combining characters when limit is reached.

Reported-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
22b77b87e1 font: Assign null_font to glyphs in ascii_font_glyph[]
The calculations in blit_comb() need information from glyph's font, e.g.
grub_font_get_xheight(main_glyph->font). However, main_glyph->font is
NULL if main_glyph comes from ascii_font_glyph[]. Therefore
grub_font_get_*() crashes because of NULL pointer.

There is already a solution, the null_font. So, assign it to those glyphs
in ascii_font_glyph[].

Reported-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
9d81f71c6b font: Harden grub_font_blit_glyph() and grub_font_blit_glyph_mirror()
As a mitigation and hardening measure add sanity checks to
grub_font_blit_glyph() and grub_font_blit_glyph_mirror(). This patch
makes these two functions do nothing if target blitting area isn't fully
contained in target bitmap. Therefore, if complex calculations in caller
overflows and malicious coordinates are given, we are still safe because
any coordinates which result in out-of-bound-write are rejected. However,
this patch only checks for invalid coordinates, and doesn't provide any
protection against invalid source glyph or destination glyph, e.g.
mismatch between glyph size and buffer size.

This hardening measure is designed to mitigate possible overflows in
blit_comb(). If overflow occurs, it may return invalid bounding box
during dry run and call grub_font_blit_glyph() with malicious
coordinates during actual blitting. However, we are still safe because
the scratch glyph itself is valid, although its size makes no sense, and
any invalid coordinates are rejected.

It would be better to call grub_fatal() if illegal parameter is detected.
However, doing this may end up in a dangerous recursion because grub_fatal()
would print messages to the screen and we are in the progress of drawing
characters on the screen.

Reported-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
992c06191b font: Fix an integer underflow in blit_comb()
The expression (ctx.bounds.height - combining_glyphs[i]->height) / 2 may
evaluate to a very big invalid value even if both ctx.bounds.height and
combining_glyphs[i]->height are small integers. For example, if
ctx.bounds.height is 10 and combining_glyphs[i]->height is 12, this
expression evaluates to 2147483647 (expected -1). This is because
coordinates are allowed to be negative but ctx.bounds.height is an
unsigned int. So, the subtraction operates on unsigned ints and
underflows to a very big value. The division makes things even worse.
The quotient is still an invalid value even if converted back to int.

This patch fixes the problem by casting ctx.bounds.height to int. As
a result the subtraction will operate on int and grub_uint16_t which
will be promoted to an int. So, the underflow will no longer happen. Other
uses of ctx.bounds.height (and ctx.bounds.width) are also casted to int,
to ensure coordinates are always calculated on signed integers.

Fixes: CVE-2022-3775

Reported-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
1eac01c147 fbutil: Fix integer overflow
Expressions like u64 = u32 * u32 are unsafe because their products are
truncated to u32 even if left hand side is u64. This patch fixes all
problems like that one in fbutil.

To get right result not only left hand side have to be u64 but it's also
necessary to cast at least one of the operands of all leaf operators of
right hand side to u64, e.g. u64 = u32 * u32 + u32 * u32 should be
u64 = (u64)u32 * u32 + (u64)u32 * u32.

For 1-bit bitmaps grub_uint64_t have to be used. It's safe because any
combination of values in (grub_uint64_t)u32 * u32 + u32 expression will
not overflow grub_uint64_t.

Other expressions like ptr + u32 * u32 + u32 * u32 are also vulnerable.
They should be ptr + (grub_addr_t)u32 * u32 + (grub_addr_t)u32 * u32.

This patch also adds a comment to grub_video_fb_get_video_ptr() which
says it's arguments must be valid and no sanity check is performed
(like its siblings in grub-core/video/fb/fbutil.c).

Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
93a786a001 kern/efi/sb: Enforce verification of font files
As a mitigation and hardening measure enforce verification of font
files. Then only trusted font files can be load. This will reduce the
attack surface at cost of losing the ability of end-users to customize
fonts if e.g. UEFI Secure Boot is enabled. Vendors can always customize
fonts because they have ability to pack fonts into their GRUB bundles.

This goal is achieved by:

  * Removing GRUB_FILE_TYPE_FONT from shim lock verifier's
    skip-verification list.

  * Adding GRUB_FILE_TYPE_FONT to lockdown verifier's defer-auth list,
    so font files must be verified by a verifier before they can be loaded.

Suggested-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
1d2015598c font: Fix integer underflow in binary search of char index
If search target is less than all entries in font->index then "hi"
variable is set to -1, which translates to SIZE_MAX and leads to errors.

This patch fixes the problem by replacing the entire binary search code
with the libstdc++'s std::lower_bound() implementation.

Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
b9396daf1c font: Fix integer overflow in BMP index
The BMP index (font->bmp_idx) is designed as a reverse lookup table of
char entries (font->char_index), in order to speed up lookups for BMP
chars (i.e. code < 0x10000). The values in BMP index are the subscripts
of the corresponding char entries, stored in grub_uint16_t, while 0xffff
means not found.

This patch fixes the problem of large subscript truncated to grub_uint16_t,
leading BMP index to return wrong char entry or report false miss. The
code now checks for bounds and uses BMP index as a hint, and fallbacks
to binary-search if necessary.

On the occasion add a comment about BMP index is initialized to 0xffff.

Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
23843fe894 font: Fix integer overflow in ensure_comb_space()
In fact it can't overflow at all because glyph_id->ncomb is only 8-bit
wide. But let's keep safe if somebody changes the width of glyph_id->ncomb
in the future. This patch also fixes the inconsistency between
render_max_comb_glyphs and render_combining_glyphs when grub_malloc()
returns NULL.

Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
c51292274d font: Remove grub_font_dup_glyph()
Remove grub_font_dup_glyph() since nobody is using it since 2013, and
I'm too lazy to fix the integer overflow problem in it.

Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
768e1ef2fc font: Fix several integer overflows in grub_font_construct_glyph()
This patch fixes several integer overflows in grub_font_construct_glyph().
Glyphs of invalid size, zero or leading to an overflow, are rejected.
The inconsistency between "glyph" and "max_glyph_size" when grub_malloc()
returns NULL is fixed too.

Fixes: CVE-2022-2601

Reported-by: Zhang Boyang <zhangboyang.id@gmail.com>
Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
9c76ec09ae font: Fix size overflow in grub_font_get_glyph_internal()
The length of memory allocation and file read may overflow. This patch
fixes the problem by using safemath macros.

There is a lot of code repetition like "(x * y + 7) / 8". It is unsafe
if overflow happens. This patch introduces grub_video_bitmap_calc_1bpp_bufsz().
It is safe replacement for such code. It has safemath-like prototype.

This patch also introduces grub_cast(value, pointer), it casts value to
typeof(*pointer) then store the value to *pointer. It returns true when
overflow occurs or false if there is no overflow. The semantics of arguments
and return value are designed to be consistent with other safemath macros.

Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00
Zhang Boyang
f6b6236077 font: Reject glyphs exceeds font->max_glyph_width or font->max_glyph_height
Check glyph's width and height against limits specified in font's
metadata. Reject the glyph (and font) if such limits are exceeded.

Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2022-11-14 20:24:39 +01:00