linux/security
Enrico Bravi f83a9cd965 ima: add critical data measurement for loaded policy
IMA policy can be written multiple times in the securityfs policy file
at runtime if CONFIG_IMA_WRITE_POLICY=y. When IMA_APPRAISE_POLICY is
required, the policy needs to be signed to be loaded, writing the absolute
path of the file containing the new policy:

echo /path/of/custom_ima_policy > /sys/kernel/security/ima/policy

When this is not required, policy can be written directly, rule by rule:

echo -e "measure func=BPRM_CHECK mask=MAY_EXEC\n" \
        "audit func=BPRM_CHECK mask=MAY_EXEC\n" \
     > /sys/kernel/security/ima/policy

In this case, a new policy can be loaded without being measured or
appraised.

Add a new critical data record to measure the textual policy
representation when it becomes effective. Include in the
architecture-specific policy the new critical data record only when it
is not mandatory to load a signed policy. Additionally, enable the
policy serialization code even when CONFIG_IMA_READ_POLICY=n.

To verify the template data hash value, convert the buffer policy data
to binary:
grep "ima_policy_loaded" \
        /sys/kernel/security/integrity/ima/ascii_runtime_measurements | \
        tail -1 | cut -d' ' -f 6 | xxd -r -p | sha256sum

Signed-off-by: Enrico Bravi <enrico.bravi@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
History 2026-08-04 12:35:03 -04:00
..
apparmor apparmor: advertise the tcp fast open fix is applied 2026-06-23 22:15:15 -07:00
bpf bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized 2026-06-30 16:31:56 +02:00
integrity ima: add critical data measurement for loaded policy 2026-08-04 12:35:03 -04:00
ipe treewide: change inode->i_ino from unsigned long to u64 2026-03-06 14:31:28 +01:00
keys keys: make keyring key-chunk byte order agree with keyring_diff_objects() 2026-07-23 18:23:39 +03:00
landlock landlock: Update formatting 2026-07-10 12:59:10 +02:00
loadpin Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
lockdown lockdown: move initcalls to the LSM framework 2025-10-22 19:24:27 -04:00
safesetid Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
selinux selinux: fix incorrect execmem checks on overlayfs 2026-07-14 18:10:20 -04:00
smack security,fs,nfs,net: update security_inode_listsecurity() interface 2026-05-01 11:29:33 -04:00
tomoyo tomoyo: use u64 for holding inode->i_ino value 2026-04-15 00:00:10 +09:00
yama Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
commoncap.c security: Add KUnit tests for kuid_root_in_ns and vfsuid_root_in_currentns 2026-01-09 11:28:28 -06:00
commoncap_test.c security: Add KUnit tests for kuid_root_in_ns and vfsuid_root_in_currentns 2026-01-09 11:28:28 -06:00
device_cgroup.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
inode.c securityfs: use kstrdup_const() to manage symlink targets 2026-03-17 17:13:36 -04:00
Kconfig proc: make PROC_MEM_FORCE_PTRACE the Kconfig default 2026-04-13 09:12:37 -07:00
Kconfig.hardening security/Kconfig.hardening: Remove tautological condition from CC_HAS_RANDSTRUCT 2026-05-27 15:20:04 -07:00
lsm.h lsm: add backing_file LSM hooks 2026-04-03 16:53:50 -04:00
lsm_audit.c treewide: change inode->i_ino from unsigned long to u64 2026-03-06 14:31:28 +01:00
lsm_init.c security: lsm: allow LSMs to register for late_initcall_sync init 2026-08-04 12:35:02 -04:00
lsm_notifier.c lsm: split the notifier code out into lsm_notifier.c 2025-10-22 19:24:15 -04:00
lsm_syscalls.c lsm: hold cred_guard_mutex for lsm_set_self_attr() 2026-05-14 16:47:59 -04:00
Makefile lsm: split the init code out into lsm_init.c 2025-10-22 19:24:16 -04:00
min_addr.c lsm: preserve /proc/sys/vm/mmap_min_addr when !CONFIG_SECURITY 2026-01-29 13:56:53 -05:00
security.c security,fs,nfs,net: update security_inode_listsecurity() interface 2026-05-01 11:29:33 -04:00