cc293c8466
The init_module syscall loads an ELF image into kernel space without measuring the buffer containing the ELF image. To close this kernel module integrity gap, define a new critical-data record which includes the hash of the ELF image. Instead of including the buffer data in the IMA measurement list, include the hash of the buffer data to avoid large IMA measurement list records. The buffer data hash would be the same value as the finit_module syscall file hash. To enable measuring the init_module buffer and other critical data from boot, define "ima_policy=critical_data" on the boot command line. Since builtin policies are not persistent, a custom IMA policy must include the rule as well: measure func=CRITICAL_DATA label=modules To verify the template data hash value, first convert the buffer data hash to binary: grep "init_module" \ /sys/kernel/security/integrity/ima/ascii_runtime_measurements | \ tail -1 | cut -d' ' -f 6 | xxd -r -p | sha256sum Reported-by: Ken Goldman <kgold@linux.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
fs | ||
include | ||
init | ||
io_uring | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
rust | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.editorconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
.rustfmt.toml | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
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 reStructuredText 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.