0d2adafba9
[ Upstream commit ba3f5058db437d919f8468db50483dd9028ff688 ]
When compiling with gcc version 14.0.0 20231126 (experimental)
and CONFIG_FORTIFY_SOURCE=y, I've noticed the following:
In file included from ./include/linux/string.h:295,
from ./include/linux/bitmap.h:12,
from ./include/linux/cpumask.h:12,
from ./arch/x86/include/asm/paravirt.h:17,
from ./arch/x86/include/asm/cpuid.h:62,
from ./arch/x86/include/asm/processor.h:19,
from ./arch/x86/include/asm/cpufeature.h:5,
from ./arch/x86/include/asm/thread_info.h:53,
from ./include/linux/thread_info.h:60,
from ./arch/x86/include/asm/preempt.h:9,
from ./include/linux/preempt.h:79,
from ./include/linux/spinlock.h:56,
from ./include/linux/mmzone.h:8,
from ./include/linux/gfp.h:7,
from ./include/linux/slab.h:16,
from ./include/linux/resource_ext.h:11,
from ./include/linux/acpi.h:13,
from drivers/pnp/pnpacpi/rsparser.c:11:
In function 'fortify_memcpy_chk',
inlined from 'pnpacpi_parse_allocated_vendor' at drivers/pnp/pnpacpi/rsparser.c:158:3,
inlined from 'pnpacpi_allocated_resource' at drivers/pnp/pnpacpi/rsparser.c:249:3:
./include/linux/fortify-string.h:588:25: warning: call to '__read_overflow2_field'
declared with attribute warning: detected read beyond size of field (2nd parameter);
maybe use struct_group()? [-Wattribute-warning]
588 | __read_overflow2_field(q_size_field, size);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
According to the comments in include/linux/fortify-string.h, 'memcpy()',
'memmove()' and 'memset()' must not be used beyond individual struct
members to ensure that the compiler can enforce protection against
buffer overflows, and, IIUC, this also applies to partial copies from
the particular member ('vendor->byte_data' in this case). So it should
be better (and safer) to do both copies at once (and 'byte_data' of
'struct acpi_resource_vendor_typed' seems to be a good candidate for
'__counted_by(byte_length)' as well).
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.