Generating the canary at build time allows the canary to be different for
every build which could limit the effectiveness of certain exploits.
Fallback to the statically generated random bytes if /dev/urandom is not
readable, e.g. Windows.
On 32-bit architectures, which use a 32-bit canary, reduce the canary to
4 bytes with one byte being NUL to filter out string buffer overflow attacks.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The canary, __stack_chk_guard, is in the BSS and so will get initialized to
zero if it is not explicitly initialized. If the UEFI firmware does not
support the RNG protocol, then the canary will not be randomized and will
be zero. This seems like a possibly easier value to write by an attacker.
Initialize canary to static random bytes, so that it is still random when
there is no RNG protocol. Set at least one byte to NUL to protect against
string buffer overflow attacks [1]. Code that writes NUL terminated strings
will terminate when a NUL is encountered in the input byte stream. So the
attacker will not be able to forge the canary by including it in the input
stream without terminating the string operation and thus limiting the
stack corruption.
[1] https://www.sans.org/blog/stack-canaries-gingerly-sidestepping-the-cage/
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
In grub-core/gfxmenu/gui_image.c, Coverity detected a double free in the
function load_image(). The function checks if self->bitmap and self->raw_bitmap
aren't NULL and then frees them. In the case self->bitmap and self->raw_bitmap
are the same, only self->raw_bitmap is freed which would also free the memory
used by self->bitmap. However, in this case self->bitmap isn't being set to NULL
which could lead to a double free later in the code. After self->raw_bitmap is
freed, it gets set to the variable bitmap. If this variable is NULL, the code
could have a path that would free self->bitmap a second time in the function
rescale_image().
Fixes: CID 292472
Signed-off-by: Alec Brown <alec.r.brown@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
According to the ACPI specification the XSDT Entry field contains an array
of 64-bit physical addresses which points to other DESCRIPTION_HEADERs. However,
the entry_ptr iterator is defined as a 32-bit pointer. It means each 64-bit
entry in the XSDT table is treated as two separate 32-bit entries then. Fix the
issue by using correct addresses sizes when processing RSDT and XSDT tables.
Signed-off-by: Qiumiao Zhang <zhangqiumiao1@huawei.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
NetBSD uses slightly different function names for the same functions.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
There is some variance in how compiler treats sizeof() especially
on 32-bit platforms where it can be naturally either int or long.
Explicit cast solves the issue.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The HAVE_LIBZFS is defined by libzfs test and hence conflicts with
manual definition. On NetBSD it ends up detecting zfs but not detecting
nvpair and creates confusion. Split them.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Wrong function and variable name cause a stupid compilation error on
NetBSD and OpenBSD. Only NetBSD and OpenBSD use this file. No other
platform is affected.
Additionally, define RAW_FLOPPY_MAJOR constant if it is missing.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
After recent change in blocklist types we have a type mismatch. Fixing it
requires a wrapper or large changes. I feel like wrapper makes more sense.
Without this patch we end up with a compilation problem and without wrapping
callback data is not passed properly anymore.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Variable e is set but never used. We can just remove it now.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
We don't really control the small aspects of generated files and NetBSD
version has an unused variable that is then detected by gcc as warning
that is then promoted to error.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Current code implicitly assumes that aligning chunk_size + *kern_end is
the same as aligning on curload which is not the case because
chunk_size starts at zero even if *kern_end is unaligned and ALIGN_PAGE
moved curload to an aligned position but not *kern_end + chunk_size.
This fixes booting of FreeBSD with zfs module.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The commit 154dcb1ae (build: Allow explicit module dependencies) broke
out of tree builds by introducing the extra_deps.lst file into the
source tree but referencing it just by name in grub-core/Makefile.am.
Fix it by adding $(top_srcdir)/grub-core to the path.
Fixes: 154dcb1ae (build: Allow explicit module dependencies)
Signed-off-by: Mate Kukri <mate.kukri@canonical.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Replace definition of HTTP_PORT with a pre-processor macro that converts
the constant to the correct grub_uint16_t type.
Change "port" local variable definition in http_establish() to have the
same type.
Signed-off-by: Mate Kukri <mate.kukri@canonical.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com
If validation has been disabled via MokSbState, secure boot on the
firmware is still enabled, and the kernel fails to boot.
This is a bit hacky, because shim_lock is not *fully* enabled, but
it triggers the right code paths.
Ultimately, all this will be resolved by shim gaining it's own image
loading and starting protocol, so this is more a temporary workaround.
Fixes: 6425c12cd (efi: Fallback to legacy mode if shim is loaded on x86 archs)
Cc: Peter Jones <pjones@redhat.com>
Cc: Michael Chang <mchang@suse.com>
Signed-off-by: Julian Andres Klode <julian.klode@canonical.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The bli module has a "hidden" dependency on the part_gpt module, which
is not picked up automatically by the build system. One purpose of the
bli module is to communicate the GPT UUID of the partition GRUB was
launched from to Linux user-space (systemd-gpt-auto-generator).
Without the part_gpt module, bli is not able to obtain the UUID. Since
bli does its work in the module initialization function, the order in
which the modules are loaded is also important: part_gpt needs to be
loaded before the bli module.
To solve this, track this dependency explicitly.
Note that the Boot Loader Interface specification, which bli aims to
implement, requires GPT formatted drives. The bli module ignores all
other partition formats.
Signed-off-by: Oliver Steffen <osteffen@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The build system deduces inter-module dependencies from the symbols
required and exported by the modules. This works well, except for some
rare cases where the dependency is indirect or hidden. A module might
not make use of any function of some other module, but still expect its
functionality to be available to GRUB.
To solve this, introduce a new file, currently empty, called extra_deps.lst
to track these cases manually. This file gets processed in the same way
as the automatically generated syminfo.lst, making it possible to inject
data into the dependency resolver.
Since *.lst files are set to be ignored by git, add an exception for
extra_deps.lst.
Additionally, introduce a new keyword for the syminfo.lst syntax:
"depends" allows specifying a module dependency directly:
depends <module> <depdendency>...
Signed-off-by: Oliver Steffen <osteffen@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Display upper_mem_limit and its rounded-down value in MiB.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
On PowerVM and KVM on Power use the new memory allocation function that
honors restrictions on which memory GRUB can actually use. In the request
structure indicate the request for a single memory block along with
address alignment restrictions. Request direct usage of the memory block
by setting init_region to false (prevent it from being added to GRUB's
heap). Initialize the found addr to -1, so that -1 will be returned
to the loader in case no memory could be allocated.
Report an out-of-memory error in case the initrd could not be loaded.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Pavithra Prakash <pavrampu@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Carolyn Scherrer <cpscherr@us.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Introduce flags to identify PowerVM and KVM on Power and set them where
each type of host has been detected.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Pavithra Prakash <pavrampu@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Carolyn Scherrer <cpscherr@us.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Rename regions_claim() to grub_regions_claim() to make it available for
memory allocation. The ieee1275 loader will use this function on PowerVM
and KVM on Power and thus avoid usage of memory that it is not allowed
to use.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Pavithra Prakash <pavrampu@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Carolyn Scherrer <cpscherr@us.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Add support for memory alignment requirements and adjust a candidate
address to it before checking whether the block is large enough. This
must be done in this order since the alignment adjustment can make
a block smaller than what was requested.
None of the current callers has memory alignment requirements but the
ieee1275 loader for kernel and initrd will use it to convey them.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Pavithra Prakash <pavrampu@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Carolyn Scherrer <cpscherr@us.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Return the allocated address of the memory block in the request structure
if a memory allocation was actually done. Leave the address untouched
otherwise. This enables a caller who wants to use the allocated memory
directly, rather than adding the memory to the heap, to see where memory
was allocated. None of the current callers need this but the converted
ieee1275 loader will make use of it.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Pavithra Prakash <pavrampu@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Carolyn Scherrer <cpscherr@us.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Let the regions_claim() request structure's init_region determine whether
to call grub_mm_init_region() on it. This allows for adding memory to
GRUB's memory heap if init_region is set to true, or direct usage of the
memory otherwise. Set all current callers' init_region to true since they
want to add memory regions to GRUB's heap.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Pavithra Prakash <pavrampu@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Carolyn Scherrer <cpscherr@us.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
The regions_claim() function limits the allocation of memory regions
by excluding certain memory areas from being used by GRUB. This for
example includes a gap between 640MB and 768MB as well as an upper
limit beyond which no memory may be used when an fadump is present.
However, the ieee1275 loader for kernel and initrd currently does not
use regions_claim() for memory allocation on PowerVM and KVM on Power
and therefore may allocate memory in those areas that it should not use.
To make the regions_claim() function more flexible and ultimately usable
for the ieee1275 loader, introduce a request structure to pass various
parameters to the regions_claim() function that describe the properties
of requested memory chunks. In a first step, move the total and flags
variables into this structure.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Pavithra Prakash <pavrampu@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Carolyn Scherrer <cpscherr@us.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
XFS introduced 64-bit extent counters for inodes via a series of
upstream commits and the feature was marked as stable in v6.5 via
commit 61d7e8274cd8 (xfs: drop EXPERIMENTAL tag for large extent
counts).
Further, xfsprogs release v6.5.0 switched this feature on by default
in mkfs.xfs via commit e5b18d7d1d96 (mkfs: enable large extent counts
by default).
Filesystems formatted with large extent count support, nrext64=1, are
thus currently not recognizable by GRUB, since this is an incompat
feature. Add the required support so that those filesystems and inodes
with large extent counters can be read by GRUB.
Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
Reviewed-by: Andrey Albershteyn <aalbersh@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Marta Lewandowska <mlewando@redhat.com>
Tested-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
With new alignment specification it's easy to screw up. Fortunately if it
happens the size will be bigger than intended. Compile time assert will catch
this.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
On ia64 alignment requirements are strict. When we pass a pointer to
UUID it needs to be at least 4-byte aligned or EFI will crash.
On the other hand in device path there is no padding for UUID, so we
need 2 types in one formor another. Make 4-byte aligned and unaligned types
The code is structured in a way to accept unaligned inputs
in most cases and supply 4-byte aligned outputs.
Efiemu case is a bit ugly because there inputs and outputs are
reversed and so we need careful casts to account for this
inversion.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
We do table search in many places doing exactly the same algorithm.
The only minor variance in users is which table is used if several entries
are present. As specification mandates uniqueness and even if it ever isn't,
first entry is good enough, unify this code and always use the first entry.
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
known_protocols isn't used anywhere else and even misses grub_ prefix, so
let's make it local (static).
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The XFS directory entry parsing code has never been completely correct
for extent based directories. The parser correctly handles the case
where the directory is contained in a single extent, but then mistakenly
assumes the data blocks for the multiple extent case are each identical
to the single extent case. The difference in the format of the data
blocks between the two cases is tiny enough that its gone unnoticed for
a very long time.
A recent change introduced some additional bounds checking into the XFS
parser. Like GRUB's existing parser, it is correct for the single extent
case but incorrect for the multiple extent case. When parsing a directory
with multiple extents, this new bounds checking is sometimes (but not
always) tripped and triggers an "invalid XFS directory entry" error. This
probably would have continued to go unnoticed but the /boot/grub/<arch>
directory is large enough that it often has multiple extents.
The difference between the two cases is that when there are multiple
extents, the data blocks do not contain a trailer nor do they contain
any leaf information. That information is stored in a separate set of
extents dedicated to just the leaf information. These extents come after
the directory entry extents and are not included in the inode size. So
the existing parser already ignores the leaf extents.
The only reason to read the trailer/leaf information at all is so that
the parser can avoid misinterpreting that data as directory entries. So
this updates the parser as follows:
For the single extent case the parser doesn't change much:
1. Read the size of the leaf information from the trailer
2. Set the end pointer for the parser to the start of the leaf
information. (The previous bounds checking set the end pointer to the
start of the trailer, so this is actually a small improvement.)
3. Set the entries variable to the expected number of directory entries.
For the multiple extent case:
1. Set the end pointer to the end of the block.
2. Do not set up the entries variable. Figuring out how many entries are
in each individual block is complex and does not seem worth it when
it appears to be safe to just iterate over the entire block.
The bounds check itself was also dependent upon the faulty XFS parser
because it accidentally used "filename + length - 1". Presumably this
was able to pass the fuzzer because in the old parser there was always
8 bytes of slack space between the tail pointer and the actual end of
the block. Since this is no longer the case the bounds check needs to be
updated to "filename + length + 1" in order to prevent a regression in
the handling of corrupt fliesystems.
Notes:
* When there is only one extent there will only ever be one block. If
more than one block is required then XFS will always switch to holding
leaf information in a separate extent.
* B-tree based directories seems to be parsed properly by the same code
that handles multiple extents. This is unlikely to ever occur within
/boot though because its only used when there are an extremely large
number of directory entries.
Fixes: ef7850c75 (fs/xfs: Fix issues found while fuzzing the XFS filesystem)
Fixes: b2499b29c (Adds support for the XFS filesystem.)
Fixes: https://savannah.gnu.org/bugs/?64376
Signed-off-by: Jon DeVree <nuxi@vault24.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Tested-by: Marta Lewandowska <mlewando@redhat.com>
After parsing of the current entry, the entry pointer is advanced
to the next entry at the end of the "for" loop. In case where the
last entry is at the end of the data boundary, the advanced entry
pointer can point off the data boundary. The subsequent boundary
check for the advanced entry pointer can cause a failure.
The fix is to include the boundary check into the "for" loop
condition.
Signed-off-by: Lidong Chen <lidong.chen@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Tested-by: Marta Lewandowska <mlewando@redhat.com>
Original commit is wrong because grub_file_get_device_name() may return NULL
if we use implicit $root. Additionally, the grub_errno is guaranteed to be
GRUB_ERR_NONE at the beginning of a command. So, everything should work as
expected and Coverity report, CID 73668, WRT to this code should be treated
as false positive.
This reverts commit 7aab03418 (zfsinfo: Correct a check for error allocating memory).
Fixes: 7aab03418 (zfsinfo: Correct a check for error allocating memory)
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Current code imposes limitations on the amount of sectors read in
a single call according to CHS layout of the disk even in LBA
read mode. There's no need to obey CHS layout restrictions for
LBA reads on LBA disks. It only slows down booting process.
See: https://lore.kernel.org/grub-devel/d42a11fa-2a59-b5e7-08b1-d2c60444bb99@valdikss.org.ru/
Signed-off-by: ValdikSS <iam@valdikss.org.ru>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The code flushes the cache on VIA processors unconditionally which
is excessive. Check for cpuid family and execute wbinvd only on C3
and earlier.
Fixes: https://savannah.gnu.org/bugs/?45149
Fixes: 25492a0f0 (Add wbinvd around bios call.)
Signed-off-by: ValdikSS <iam@valdikss.org.ru>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Implicit holes in file data need to be zeroed explicitly, instead of
just leaving the data in the buffer uninitialized.
This led to kernels randomly failing to boot in "fun" ways when loaded
from btrfs with the no_holes feature enabled, because large blocks of
zeros in the kernel file contained random data instead.
Signed-off-by: Fabian Vogt <fvogt@suse.de>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
When a kernel dump is present then restrict the high memory regions to
avoid allocating memory where the kernel dump resides. Use the
ibm,kernel-dump node under /rtas to determine whether a kernel dump
exists and up to which limit GRUB can use available memory. Set the
upper_mem_limit to the size of the kernel dump section of type
REAL_MODE_REGION and therefore only allow GRUB's memory usage for high
addresses from RMO_ADDR_MAX to upper_mem_limit. This means that GRUB can
use high memory in the range of RMO_ADDR_MAX (768MB) to upper_mem_limit
and the kernel-dump memory regions above upper_mem_limit remain
untouched. This change has no effect on memory allocations below
linux_rmo_save (typically at 640MB).
Also, fall back to allocating below rmo_linux_save in case the chunk of
memory there would be larger than the chunk of memory above RMO_ADDR_MAX.
This can for example occur if a free memory area is found starting at 300MB
extending up to 1GB but a kernel dump is located at 768MB and therefore
does not allow the allocation of the high memory area but requiring to use
the chunk starting at 300MB to avoid an unnecessary out-of-memory condition.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com>
Cc: Pavithra Prakash <pavrampu@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Carolyn Scherrer <cpscherr@us.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
GCC is electing to instrument grub_efi_init() to give it stack smashing
protection when configuring with --enable-stack-protector on the x86_64-efi
target. In the function prologue, the canary at the top of the stack frame
is set to the value of the stack guard. And in the epilogue, the canary is
checked to verify if it is equal to the guard and if not to call the stack
check fail function. The issue is that grub_efi_init() sets up the guard
by initializing it with random bytes, if the firmware supports the RNG
protocol. So in its prologue the canary will be set with the value of the
uninitialized guard, likely NUL bytes. Then the guard is initialized, and
finally the epilogue checks the canary against the guard, which will almost
certainly be different. This causes the code path for a smashed stack to be
taken, causing the machine to print out a message that stack smashing was
detected, wait 5 seconds, and then reboot. Disable grub_efi_init()
instrumentation so there is no stack smashing false positive generated.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The sector size in bytes is added to each line and it is allowed to be
6 decimal digits long, which covers the most common cases of 512 and 4096
byte sectors with space for two additional digits as future-proofing. The
size allocation is updated to reflect this additional field. Also make
clearer the size allocation calculation.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Use the return value of grub_snprintf() to move the string pointer forward,
instead of incrementing the string pointer iteratively until a NULL byte is
reached. Move the space out of the format string argument, a small
optimization, but also makes the spacing clearer. Also, use the new
PRIxGRUB_OFFSET instead of PRIuGRUB_UINT64_T to accurately reflect the
format string for this type.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
A large enough argument to the --port option could cause a string buffer
to be not NULL terminated because grub_strncpy() does not guarantee NULL
termination if copied string is longer than max characters to copy.
Fixes: 712309eaae04 (term/serial: Use grub_strncpy() instead of grub_snprintf() when only copying string)
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
E.g. 2.10 instead of 00020064 and 2.3.1 instead of 0002001f.
See UEFI 2.10 specification, chapter 4.2.1 EFI_TABLE_HEADER.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Move some calls used to access NTFS attribute header fields into
functions with human-readable names.
Suggested-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Maxim Suhanov <dfirblog@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This fix introduces checks to ensure that an NTFS volume label is always
read from the corresponding file record segment.
The current NTFS code allows the volume label string to be read from an
arbitrary, attacker-chosen memory location. However, the bytes read are
always treated as UTF-16LE. So, the final string displayed is mostly
unreadable and it can't be easily converted back to raw bytes.
The lack of this check is a minor issue, likely not causing a significant
data leak.
Reported-by: Maxim Suhanov <dfirblog@gmail.com>
Signed-off-by: Maxim Suhanov <dfirblog@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This fix introduces checks to ensure that bitmaps for directory indices
are never read beyond their actual sizes.
The lack of this check is a minor issue, likely not exploitable in any way.
Reported-by: Maxim Suhanov <dfirblog@gmail.com>
Signed-off-by: Maxim Suhanov <dfirblog@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This fix introduces checks to ensure that index entries are never read
beyond the corresponding directory index.
The lack of this check is a minor issue, likely not exploitable in any way.
Reported-by: Maxim Suhanov <dfirblog@gmail.com>
Signed-off-by: Maxim Suhanov <dfirblog@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
When reading a file containing resident data, i.e., the file data is stored in
the $DATA attribute within the NTFS file record, not in external clusters,
there are no checks that this resident data actually fits the corresponding
file record segment.
When parsing a specially-crafted file system image, the current NTFS code will
read the file data from an arbitrary, attacker-chosen memory offset and of
arbitrary, attacker-chosen length.
This allows an attacker to display arbitrary chunks of memory, which could
contain sensitive information like password hashes or even plain-text,
obfuscated passwords from BS EFI variables.
This fix implements a check to ensure that resident data is read from the
corresponding file record segment only.
Fixes: CVE-2023-4693
Reported-by: Maxim Suhanov <dfirblog@gmail.com>
Signed-off-by: Maxim Suhanov <dfirblog@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
When parsing an extremely fragmented $MFT file, i.e., the file described
using the $ATTRIBUTE_LIST attribute, current NTFS code will reuse a buffer
containing bytes read from the underlying drive to store sector numbers,
which are consumed later to read data from these sectors into another buffer.
These sectors numbers, two 32-bit integers, are always stored at predefined
offsets, 0x10 and 0x14, relative to first byte of the selected entry within
the $ATTRIBUTE_LIST attribute. Usually, this won't cause any problem.
However, when parsing a specially-crafted file system image, this may cause
the NTFS code to write these integers beyond the buffer boundary, likely
causing the GRUB memory allocator to misbehave or fail. These integers contain
values which are controlled by on-disk structures of the NTFS file system.
Such modification and resulting misbehavior may touch a memory range not
assigned to the GRUB and owned by firmware or another EFI application/driver.
This fix introduces checks to ensure that these sector numbers are never
written beyond the boundary.
Fixes: CVE-2023-4692
Reported-by: Maxim Suhanov <dfirblog@gmail.com>
Signed-off-by: Maxim Suhanov <dfirblog@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
