linux/security
Roberto Sassu 280fe8367b ima: Always return a file measurement in ima_file_hash()
__ima_inode_hash() checks if a digest has been already calculated by
looking for the integrity_iint_cache structure associated to the passed
inode.

Users of ima_file_hash() (e.g. eBPF) might be interested in obtaining the
information without having to setup an IMA policy so that the digest is
always available at the time they call this function.

In addition, they likely expect the digest to be fresh, e.g. recalculated
by IMA after a file write. Although getting the digest from the
bprm_committed_creds hook (as in the eBPF test) ensures that the digest is
fresh, as the IMA hook is executed before that hook, this is not always the
case (e.g. for the mmap_file hook).

Call ima_collect_measurement() in __ima_inode_hash(), if the file
descriptor is available (passed by ima_file_hash()) and the digest is not
available/not fresh, and store the file measurement in a temporary
integrity_iint_cache structure.

This change does not cause memory usage increase, due to using the
temporary integrity_iint_cache structure, and due to freeing the
ima_digest_data structure inside integrity_iint_cache before exiting from
__ima_inode_hash().

For compatibility reasons, the behavior of ima_inode_hash() remains
unchanged.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20220302111404.193900-3-roberto.sassu@huawei.com
2022-03-10 18:56:24 -08:00
..
apparmor lsm: security_task_getsecid_subj() -> security_current_getsecid_subj() 2021-11-22 17:52:47 -05:00
bpf bpf: Implement task local storage 2020-11-06 08:08:37 -08:00
integrity ima: Always return a file measurement in ima_file_hash() 2022-03-10 18:56:24 -08:00
keys security: DH - use KDF implementation from crypto API 2021-11-26 16:25:17 +11:00
landlock landlock: Enable user space to infer supported features 2021-04-22 12:22:11 -07:00
loadpin LSM: Add "contents" flag to kernel_read_file hook 2020-10-05 13:37:03 +02:00
lockdown Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2020-06-02 17:36:24 -07:00
safesetid LSM: SafeSetID: Mark safesetid_initialized as __initdata 2021-06-10 09:52:32 -07:00
selinux net: rtnetlink: Add RTM_SETSTATS 2022-03-03 10:37:23 +00:00
smack lsm: security_task_getsecid_subj() -> security_current_getsecid_subj() 2021-11-22 17:52:47 -05:00
tomoyo tomoyo: use hwight16() in tomoyo_domain_quota_is_ok() 2021-12-15 20:13:55 +09:00
yama task_work: cleanup notification modes 2020-10-17 15:05:30 -06:00
commoncap.c fs: support mapped mounts of mapped filesystems 2021-12-05 10:28:57 +01:00
device_cgroup.c bpf: Make BPF_PROG_RUN_ARRAY return -err instead of allow boolean 2022-01-19 12:51:30 -08:00
inode.c Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
Kconfig Merge branch 'akpm' (patches from Andrew) 2021-11-06 14:08:17 -07:00
Kconfig.hardening gcc-plugins: Explicitly document purpose and deprecation schedule 2021-10-21 08:41:38 -07:00
lsm_audit.c lsm_audit: avoid overloading the "key" audit field 2021-09-19 22:47:04 -04:00
Makefile security: remove unneeded subdir-$(CONFIG_...) 2021-09-03 08:17:20 +09:00
min_addr.c sysctl: pass kernel pointers to ->proc_handler 2020-04-27 02:07:40 -04:00
security.c Fix NULL pointer crash in LSM via Ceph, from Vivek Goyal <vgoyal@redhat.com>. 2022-01-29 08:52:27 +02:00