[PATCH v6 22/25] ima: Remove dependency on 'integrity' LSM
Roberto Sassu
roberto.sassu at huaweicloud.com
Mon Nov 20 17:33:15 UTC 2023
From: Roberto Sassu <roberto.sassu at huawei.com>
Remove the dependency on the 'integrity' LSM by introducing IMA own
integrity metadata (ima_iint_cache structure, with IMA-specific fields from
the integrity_iint_cache structure), and by managing it directly from the
'ima' LSM.
First, replace integrity_iint_cache with ima_iint_cache in various places
of the IMA code.
Then, reserve space in the security blob for the entire ima_iint_cache
structure, so that retrieval of integrity metadata always succeeds, as
opposed to when integrity_inode_get() was called, which could fail. Adjust
the IMA code accordingly, call ima_inode_get_iint() to retrieve the
ima_iint_cache structure, and remove the now unnecessary non-NULL checks.
Don't include the inode pointer as field in the ima_iint_cache structure,
since the association with the inode is clear. Since the inode field is
missing in ima_iint_cache, pass the extra inode parameter to
ima_get_verity_digest().
Also, since IMA and EVM at this point are using different structures to
store integrity metadata, pass NULL to evm_verifyxattr(). Unfortunately,
this alone does not work, since EVM is expecting IMA to have allocated
integrity metadata with integrity_inode_get(), for files being appraised.
Since this is not true anymore, the integrity_iint_find() call in EVM
always returns NULL making it impossible for EVM to access integrity
metadata. Temporary fix this issue by forcing the creation of integrity
metadata with integrity_inode_get().
Finally, register ima_inode_alloc_security() for the inode_alloc_security
LSM hook, to initialize the new ima_iint_cache structure (before this task
was done by iint_init_always()). Also, duplicate iint_lockdep_annotate()
for the ima_iint_cache structure, and name it ima_iint_lockdep_annotate().
Signed-off-by: Roberto Sassu <roberto.sassu at huawei.com>
---
security/integrity/evm/evm_main.c | 4 +-
security/integrity/ima/ima.h | 57 +++++++++----
security/integrity/ima/ima_api.c | 15 ++--
security/integrity/ima/ima_appraise.c | 35 ++++----
security/integrity/ima/ima_init.c | 2 +-
security/integrity/ima/ima_main.c | 111 ++++++++++++++------------
security/integrity/ima/ima_policy.c | 2 +-
7 files changed, 129 insertions(+), 97 deletions(-)
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index f1ce9d0a490f..1e59a985b845 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -409,7 +409,7 @@ enum integrity_status evm_verifyxattr(struct dentry *dentry,
return INTEGRITY_UNKNOWN;
if (!iint) {
- iint = integrity_iint_find(d_backing_inode(dentry));
+ iint = integrity_inode_get(d_backing_inode(dentry));
if (!iint)
return INTEGRITY_UNKNOWN;
}
@@ -984,7 +984,7 @@ evm_post_path_mknod(struct mnt_idmap *idmap, struct dentry *dentry)
{
struct integrity_iint_cache *iint;
- iint = integrity_iint_find(d_backing_inode(dentry));
+ iint = integrity_inode_get(d_backing_inode(dentry));
if (iint)
/* needed for successful verification of empty files */
iint->flags |= IMA_NEW_FILE;
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index a27fc10f84f7..7c94277f2929 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -60,7 +60,7 @@ extern const char boot_aggregate_name[];
/* IMA event related data */
struct ima_event_data {
- struct integrity_iint_cache *iint;
+ struct ima_iint_cache *iint;
struct file *file;
const unsigned char *filename;
struct evm_ima_xattr_data *xattr_value;
@@ -119,6 +119,34 @@ struct ima_kexec_hdr {
u64 count;
};
+/* IMA integrity metadata associated with an inode */
+struct ima_iint_cache {
+ struct mutex mutex; /* protects: version, flags, digest */
+ u64 version; /* track inode changes */
+ unsigned long flags;
+ unsigned long measured_pcrs;
+ unsigned long atomic_flags;
+ unsigned long real_ino;
+ dev_t real_dev;
+ enum integrity_status ima_file_status:4;
+ enum integrity_status ima_mmap_status:4;
+ enum integrity_status ima_bprm_status:4;
+ enum integrity_status ima_read_status:4;
+ enum integrity_status ima_creds_status:4;
+ struct ima_digest_data *ima_hash;
+};
+
+extern struct lsm_blob_sizes ima_blob_sizes;
+
+static inline struct ima_iint_cache *
+ima_inode_get_iint(const struct inode *inode)
+{
+ struct ima_iint_cache *ima_iint_sec;
+
+ ima_iint_sec = inode->i_security + ima_blob_sizes.lbs_inode;
+ return ima_iint_sec;
+}
+
extern const int read_idmap[];
#ifdef CONFIG_HAVE_IMA_KEXEC
@@ -152,7 +180,7 @@ int ima_calc_field_array_hash(struct ima_field_data *field_data,
struct ima_template_entry *entry);
int ima_calc_boot_aggregate(struct ima_digest_data *hash);
void ima_add_violation(struct file *file, const unsigned char *filename,
- struct integrity_iint_cache *iint,
+ struct ima_iint_cache *iint,
const char *op, const char *cause);
int ima_init_crypto(void);
void ima_putc(struct seq_file *m, void *data, int datalen);
@@ -267,10 +295,10 @@ int ima_get_action(struct mnt_idmap *idmap, struct inode *inode,
struct ima_template_desc **template_desc,
const char *func_data, unsigned int *allowed_algos);
int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
-int ima_collect_measurement(struct integrity_iint_cache *iint,
+int ima_collect_measurement(struct ima_iint_cache *iint,
struct file *file, void *buf, loff_t size,
enum hash_algo algo, struct modsig *modsig);
-void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
+void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len, const struct modsig *modsig, int pcr,
@@ -280,7 +308,7 @@ int process_buffer_measurement(struct mnt_idmap *idmap,
const char *eventname, enum ima_hooks func,
int pcr, const char *func_data,
bool buf_hash, u8 *digest, size_t digest_len);
-void ima_audit_measurement(struct integrity_iint_cache *iint,
+void ima_audit_measurement(struct ima_iint_cache *iint,
const unsigned char *filename);
int ima_alloc_init_template(struct ima_event_data *event_data,
struct ima_template_entry **entry,
@@ -318,17 +346,17 @@ int ima_policy_show(struct seq_file *m, void *v);
#define IMA_APPRAISE_KEXEC 0x40
#ifdef CONFIG_IMA_APPRAISE
-int ima_check_blacklist(struct integrity_iint_cache *iint,
+int ima_check_blacklist(struct ima_iint_cache *iint,
const struct modsig *modsig, int pcr);
int ima_appraise_measurement(enum ima_hooks func,
- struct integrity_iint_cache *iint,
+ struct ima_iint_cache *iint,
struct file *file, const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len, const struct modsig *modsig);
int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode,
int mask, enum ima_hooks func);
-void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file);
-enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
+void ima_update_xattr(struct ima_iint_cache *iint, struct file *file);
+enum integrity_status ima_get_cache_status(struct ima_iint_cache *iint,
enum ima_hooks func);
enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value,
int xattr_len);
@@ -337,14 +365,14 @@ int ima_read_xattr(struct dentry *dentry,
void __init init_ima_appraise_lsm(const struct lsm_id *lsmid);
#else
-static inline int ima_check_blacklist(struct integrity_iint_cache *iint,
+static inline int ima_check_blacklist(struct ima_iint_cache *iint,
const struct modsig *modsig, int pcr)
{
return 0;
}
static inline int ima_appraise_measurement(enum ima_hooks func,
- struct integrity_iint_cache *iint,
+ struct ima_iint_cache *iint,
struct file *file,
const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
@@ -361,14 +389,13 @@ static inline int ima_must_appraise(struct mnt_idmap *idmap,
return 0;
}
-static inline void ima_update_xattr(struct integrity_iint_cache *iint,
+static inline void ima_update_xattr(struct ima_iint_cache *iint,
struct file *file)
{
}
-static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache
- *iint,
- enum ima_hooks func)
+static inline enum integrity_status
+ima_get_cache_status(struct ima_iint_cache *iint, enum ima_hooks func)
{
return INTEGRITY_UNKNOWN;
}
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 597ea0c4d72f..f3363935804f 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -131,7 +131,7 @@ int ima_store_template(struct ima_template_entry *entry,
* value is invalidated.
*/
void ima_add_violation(struct file *file, const unsigned char *filename,
- struct integrity_iint_cache *iint,
+ struct ima_iint_cache *iint,
const char *op, const char *cause)
{
struct ima_template_entry *entry;
@@ -201,7 +201,8 @@ int ima_get_action(struct mnt_idmap *idmap, struct inode *inode,
allowed_algos);
}
-static bool ima_get_verity_digest(struct integrity_iint_cache *iint,
+static bool ima_get_verity_digest(struct ima_iint_cache *iint,
+ struct inode *inode,
struct ima_max_digest_data *hash)
{
enum hash_algo alg;
@@ -211,7 +212,7 @@ static bool ima_get_verity_digest(struct integrity_iint_cache *iint,
* On failure, 'measure' policy rules will result in a file data
* hash containing 0's.
*/
- digest_len = fsverity_get_digest(iint->inode, hash->digest, NULL, &alg);
+ digest_len = fsverity_get_digest(inode, hash->digest, NULL, &alg);
if (digest_len == 0)
return false;
@@ -237,7 +238,7 @@ static bool ima_get_verity_digest(struct integrity_iint_cache *iint,
*
* Return 0 on success, error code otherwise
*/
-int ima_collect_measurement(struct integrity_iint_cache *iint,
+int ima_collect_measurement(struct ima_iint_cache *iint,
struct file *file, void *buf, loff_t size,
enum hash_algo algo, struct modsig *modsig)
{
@@ -280,7 +281,7 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
memset(&hash.digest, 0, sizeof(hash.digest));
if (iint->flags & IMA_VERITY_REQUIRED) {
- if (!ima_get_verity_digest(iint, &hash)) {
+ if (!ima_get_verity_digest(iint, inode, &hash)) {
audit_cause = "no-verity-digest";
result = -ENODATA;
}
@@ -338,7 +339,7 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
*
* Must be called with iint->mutex held.
*/
-void ima_store_measurement(struct integrity_iint_cache *iint,
+void ima_store_measurement(struct ima_iint_cache *iint,
struct file *file, const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len, const struct modsig *modsig, int pcr,
@@ -382,7 +383,7 @@ void ima_store_measurement(struct integrity_iint_cache *iint,
ima_free_template_entry(entry);
}
-void ima_audit_measurement(struct integrity_iint_cache *iint,
+void ima_audit_measurement(struct ima_iint_cache *iint,
const unsigned char *filename)
{
struct audit_buffer *ab;
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 076451109637..b0b96c263961 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -85,7 +85,7 @@ int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode,
}
static int ima_fix_xattr(struct dentry *dentry,
- struct integrity_iint_cache *iint)
+ struct ima_iint_cache *iint)
{
int rc, offset;
u8 algo = iint->ima_hash->algo;
@@ -106,7 +106,7 @@ static int ima_fix_xattr(struct dentry *dentry,
}
/* Return specific func appraised cached result */
-enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
+enum integrity_status ima_get_cache_status(struct ima_iint_cache *iint,
enum ima_hooks func)
{
switch (func) {
@@ -126,7 +126,7 @@ enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
}
}
-static void ima_set_cache_status(struct integrity_iint_cache *iint,
+static void ima_set_cache_status(struct ima_iint_cache *iint,
enum ima_hooks func,
enum integrity_status status)
{
@@ -152,8 +152,7 @@ static void ima_set_cache_status(struct integrity_iint_cache *iint,
}
}
-static void ima_cache_flags(struct integrity_iint_cache *iint,
- enum ima_hooks func)
+static void ima_cache_flags(struct ima_iint_cache *iint, enum ima_hooks func)
{
switch (func) {
case MMAP_CHECK:
@@ -276,7 +275,7 @@ static int calc_file_id_hash(enum evm_ima_xattr_type type,
*
* Return 0 on success, error code otherwise.
*/
-static int xattr_verify(enum ima_hooks func, struct integrity_iint_cache *iint,
+static int xattr_verify(enum ima_hooks func, struct ima_iint_cache *iint,
struct evm_ima_xattr_data *xattr_value, int xattr_len,
enum integrity_status *status, const char **cause)
{
@@ -443,7 +442,7 @@ static int modsig_verify(enum ima_hooks func, const struct modsig *modsig,
*
* Returns -EPERM if the hash is blacklisted.
*/
-int ima_check_blacklist(struct integrity_iint_cache *iint,
+int ima_check_blacklist(struct ima_iint_cache *iint,
const struct modsig *modsig, int pcr)
{
enum hash_algo hash_algo;
@@ -478,7 +477,7 @@ int ima_check_blacklist(struct integrity_iint_cache *iint,
* Return 0 on success, error code otherwise
*/
int ima_appraise_measurement(enum ima_hooks func,
- struct integrity_iint_cache *iint,
+ struct ima_iint_cache *iint,
struct file *file, const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len, const struct modsig *modsig)
@@ -520,7 +519,7 @@ int ima_appraise_measurement(enum ima_hooks func,
}
status = evm_verifyxattr(dentry, XATTR_NAME_IMA, xattr_value,
- rc < 0 ? 0 : rc, iint);
+ rc < 0 ? 0 : rc, NULL);
switch (status) {
case INTEGRITY_PASS:
case INTEGRITY_PASS_IMMUTABLE:
@@ -603,7 +602,7 @@ int ima_appraise_measurement(enum ima_hooks func,
/*
* ima_update_xattr - update 'security.ima' hash value
*/
-void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
+void ima_update_xattr(struct ima_iint_cache *iint, struct file *file)
{
struct dentry *dentry = file_dentry(file);
int rc = 0;
@@ -640,7 +639,7 @@ static void ima_inode_post_setattr(struct mnt_idmap *idmap,
struct dentry *dentry, int ia_valid)
{
struct inode *inode = d_backing_inode(dentry);
- struct integrity_iint_cache *iint;
+ struct ima_iint_cache *iint = ima_inode_get_iint(inode);
int action;
if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode)
@@ -648,12 +647,9 @@ static void ima_inode_post_setattr(struct mnt_idmap *idmap,
return;
action = ima_must_appraise(idmap, inode, MAY_ACCESS, POST_SETATTR);
- iint = integrity_iint_find(inode);
- if (iint) {
- set_bit(IMA_CHANGE_ATTR, &iint->atomic_flags);
- if (!action)
- clear_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
- }
+ set_bit(IMA_CHANGE_ATTR, &iint->atomic_flags);
+ if (!action)
+ clear_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
}
/*
@@ -674,14 +670,11 @@ static int ima_protect_xattr(struct dentry *dentry, const char *xattr_name,
static void ima_reset_appraise_flags(struct inode *inode, int digsig)
{
- struct integrity_iint_cache *iint;
+ struct ima_iint_cache *iint = ima_inode_get_iint(inode);
if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode))
return;
- iint = integrity_iint_find(inode);
- if (!iint)
- return;
iint->measured_pcrs = 0;
set_bit(IMA_CHANGE_XATTR, &iint->atomic_flags);
if (digsig)
diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c
index 63979aefc95f..393f5c7912d5 100644
--- a/security/integrity/ima/ima_init.c
+++ b/security/integrity/ima/ima_init.c
@@ -44,7 +44,7 @@ static int __init ima_add_boot_aggregate(void)
static const char op[] = "add_boot_aggregate";
const char *audit_cause = "ENOMEM";
struct ima_template_entry *entry;
- struct integrity_iint_cache tmp_iint, *iint = &tmp_iint;
+ struct ima_iint_cache tmp_iint, *iint = &tmp_iint;
struct ima_event_data event_data = { .iint = iint,
.filename = boot_aggregate_name };
struct ima_max_digest_data hash;
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 3b5d53a7f755..737bca82dd5a 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -114,7 +114,7 @@ static int mmap_violation_check(enum ima_hooks func, struct file *file,
*
*/
static void ima_rdwr_violation_check(struct file *file,
- struct integrity_iint_cache *iint,
+ struct ima_iint_cache *iint,
int must_measure,
char **pathbuf,
const char **pathname,
@@ -125,12 +125,9 @@ static void ima_rdwr_violation_check(struct file *file,
bool send_tomtou = false, send_writers = false;
if (mode & FMODE_WRITE) {
- if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) {
- if (!iint)
- iint = integrity_iint_find(inode);
+ if (atomic_read(&inode->i_readcount)) {
/* IMA_MEASURE is set from reader side */
- if (iint && test_bit(IMA_MUST_MEASURE,
- &iint->atomic_flags))
+ if (test_bit(IMA_MUST_MEASURE, &iint->atomic_flags))
send_tomtou = true;
}
} else {
@@ -153,7 +150,7 @@ static void ima_rdwr_violation_check(struct file *file,
"invalid_pcr", "open_writers");
}
-static void ima_check_last_writer(struct integrity_iint_cache *iint,
+static void ima_check_last_writer(struct ima_iint_cache *iint,
struct inode *inode, struct file *file)
{
fmode_t mode = file->f_mode;
@@ -192,15 +189,11 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint,
static void ima_file_free(struct file *file)
{
struct inode *inode = file_inode(file);
- struct integrity_iint_cache *iint;
+ struct ima_iint_cache *iint = ima_inode_get_iint(inode);
if (!ima_policy_flag || !S_ISREG(inode->i_mode))
return;
- iint = integrity_iint_find(inode);
- if (!iint)
- return;
-
ima_check_last_writer(iint, inode, file);
}
@@ -209,7 +202,7 @@ static int process_measurement(struct file *file, const struct cred *cred,
enum ima_hooks func)
{
struct inode *backing_inode, *inode = file_inode(file);
- struct integrity_iint_cache *iint = NULL;
+ struct ima_iint_cache *iint = ima_inode_get_iint(inode);
struct ima_template_desc *template_desc = NULL;
char *pathbuf = NULL;
char filename[NAME_MAX];
@@ -247,20 +240,12 @@ static int process_measurement(struct file *file, const struct cred *cred,
inode_lock(inode);
- if (action) {
- iint = integrity_inode_get(inode);
- if (!iint)
- rc = -ENOMEM;
- }
-
- if (!rc && violation_check)
+ if (violation_check)
ima_rdwr_violation_check(file, iint, action & IMA_MEASURE,
&pathbuf, &pathname, filename);
inode_unlock(inode);
- if (rc)
- goto out;
if (!action)
goto out;
@@ -564,21 +549,11 @@ static int ima_file_check(struct file *file, int mask)
static int __ima_inode_hash(struct inode *inode, struct file *file, char *buf,
size_t buf_size)
{
- struct integrity_iint_cache *iint = NULL, tmp_iint;
+ struct ima_iint_cache *iint = ima_inode_get_iint(inode), tmp_iint;
int rc, hash_algo;
- if (ima_policy_flag) {
- iint = integrity_iint_find(inode);
- if (iint)
- mutex_lock(&iint->mutex);
- }
-
- if ((!iint || !(iint->flags & IMA_COLLECTED)) && file) {
- if (iint)
- mutex_unlock(&iint->mutex);
-
+ if ((!(iint->flags & IMA_COLLECTED)) && file) {
memset(&tmp_iint, 0, sizeof(tmp_iint));
- tmp_iint.inode = inode;
mutex_init(&tmp_iint.mutex);
rc = ima_collect_measurement(&tmp_iint, file, NULL, 0,
@@ -592,11 +567,9 @@ static int __ima_inode_hash(struct inode *inode, struct file *file, char *buf,
}
iint = &tmp_iint;
- mutex_lock(&iint->mutex);
}
- if (!iint)
- return -EOPNOTSUPP;
+ mutex_lock(&iint->mutex);
/*
* ima_file_hash can be called when ima_collect_measurement has still
@@ -688,7 +661,7 @@ static void ima_post_create_tmpfile(struct mnt_idmap *idmap,
struct inode *inode)
{
- struct integrity_iint_cache *iint;
+ struct ima_iint_cache *iint = ima_inode_get_iint(inode);
int must_appraise;
if (!ima_policy_flag || !S_ISREG(inode->i_mode))
@@ -699,11 +672,6 @@ static void ima_post_create_tmpfile(struct mnt_idmap *idmap,
if (!must_appraise)
return;
- /* Nothing to do if we can't allocate memory */
- iint = integrity_inode_get(inode);
- if (!iint)
- return;
-
/* needed for writing the security xattrs */
set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
iint->ima_file_status = INTEGRITY_PASS;
@@ -720,8 +688,8 @@ static void ima_post_create_tmpfile(struct mnt_idmap *idmap,
static void __maybe_unused
ima_post_path_mknod(struct mnt_idmap *idmap, struct dentry *dentry)
{
- struct integrity_iint_cache *iint;
struct inode *inode = dentry->d_inode;
+ struct ima_iint_cache *iint = ima_inode_get_iint(inode);
int must_appraise;
if (!ima_policy_flag || !S_ISREG(inode->i_mode))
@@ -732,11 +700,6 @@ ima_post_path_mknod(struct mnt_idmap *idmap, struct dentry *dentry)
if (!must_appraise)
return;
- /* Nothing to do if we can't allocate memory */
- iint = integrity_inode_get(inode);
- if (!iint)
- return;
-
/* needed for re-opening empty files */
iint->flags |= IMA_NEW_FILE;
}
@@ -936,7 +899,7 @@ int process_buffer_measurement(struct mnt_idmap *idmap,
int ret = 0;
const char *audit_cause = "ENOMEM";
struct ima_template_entry *entry = NULL;
- struct integrity_iint_cache iint = {};
+ struct ima_iint_cache iint = {};
struct ima_event_data event_data = {.iint = &iint,
.filename = eventname,
.buf = buf,
@@ -1145,6 +1108,48 @@ static int __maybe_unused ima_kernel_module_request(char *kmod_name)
return 0;
}
+#define IMA_MAX_NESTING (FILESYSTEM_MAX_STACK_DEPTH + 1)
+
+/*
+ * It is not clear that IMA should be nested at all, but as long is it measures
+ * files both on overlayfs and on underlying fs, we need to annotate the iint
+ * mutex to avoid lockdep false positives related to IMA + overlayfs.
+ * See ovl_lockdep_annotate_inode_mutex_key() for more details.
+ */
+static inline void ima_iint_lockdep_annotate(struct ima_iint_cache *ima_iint,
+ struct inode *inode)
+{
+#ifdef CONFIG_LOCKDEP
+ static struct lock_class_key iint_mutex_key[IMA_MAX_NESTING];
+
+ int depth = inode->i_sb->s_stack_depth;
+
+ if (WARN_ON_ONCE(depth < 0 || depth >= IMA_MAX_NESTING))
+ depth = 0;
+
+ lockdep_set_class(&ima_iint->mutex, &iint_mutex_key[depth]);
+#endif
+}
+
+static int ima_inode_alloc_security(struct inode *inode)
+{
+ struct ima_iint_cache *iint = ima_inode_get_iint(inode);
+
+ iint->ima_hash = NULL;
+ iint->version = 0;
+ iint->flags = 0UL;
+ iint->atomic_flags = 0UL;
+ iint->ima_file_status = INTEGRITY_UNKNOWN;
+ iint->ima_mmap_status = INTEGRITY_UNKNOWN;
+ iint->ima_bprm_status = INTEGRITY_UNKNOWN;
+ iint->ima_read_status = INTEGRITY_UNKNOWN;
+ iint->ima_creds_status = INTEGRITY_UNKNOWN;
+ iint->measured_pcrs = 0;
+ mutex_init(&iint->mutex);
+ ima_iint_lockdep_annotate(iint, inode);
+ return 0;
+}
+
static struct security_hook_list ima_hooks[] __ro_after_init = {
LSM_HOOK_INIT(bprm_check_security, ima_bprm_check),
LSM_HOOK_INIT(file_post_open, ima_file_check),
@@ -1156,6 +1161,7 @@ static struct security_hook_list ima_hooks[] __ro_after_init = {
LSM_HOOK_INIT(kernel_post_load_data, ima_post_load_data),
LSM_HOOK_INIT(kernel_read_file, ima_read_file),
LSM_HOOK_INIT(kernel_post_read_file, ima_post_read_file),
+ LSM_HOOK_INIT(inode_alloc_security, ima_inode_alloc_security),
#ifdef CONFIG_SECURITY_PATH
LSM_HOOK_INIT(path_post_mknod, ima_post_path_mknod),
#endif
@@ -1185,10 +1191,15 @@ int __init init_ima_lsm(void)
return 0;
}
+struct lsm_blob_sizes ima_blob_sizes __ro_after_init = {
+ .lbs_inode = sizeof(struct ima_iint_cache),
+};
+
DEFINE_LSM(ima) = {
.name = "ima",
.init = init_ima_lsm,
.order = LSM_ORDER_LAST,
+ .blobs = &ima_blob_sizes,
};
late_initcall(init_ima); /* Start IMA after the TPM is available */
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index f69062617754..c0556907c2e6 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -49,7 +49,7 @@
#define DONT_HASH 0x0200
#define INVALID_PCR(a) (((a) < 0) || \
- (a) >= (sizeof_field(struct integrity_iint_cache, measured_pcrs) * 8))
+ (a) >= (sizeof_field(struct ima_iint_cache, measured_pcrs) * 8))
int ima_policy_flag;
static int temp_ima_appraise;
--
2.34.1
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