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-rw-r--r--security/integrity/iint.c2
-rw-r--r--security/integrity/ima/ima_appraise.c27
-rw-r--r--security/integrity/ima/ima_main.c70
-rw-r--r--security/integrity/integrity.h18
4 files changed, 77 insertions, 40 deletions
diff --git a/security/integrity/iint.c b/security/integrity/iint.c
index 6fc888ca468e..2db461c38795 100644
--- a/security/integrity/iint.c
+++ b/security/integrity/iint.c
@@ -155,12 +155,14 @@ static void init_once(void *foo)
memset(iint, 0, sizeof(*iint));
iint->version = 0;
iint->flags = 0UL;
+ iint->atomic_flags = 0;
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->evm_status = INTEGRITY_UNKNOWN;
iint->measured_pcrs = 0;
+ mutex_init(&iint->mutex);
}
static int __init integrity_iintcache_init(void)
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index e91d28cc05cc..84eb6cc956bf 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -251,6 +251,7 @@ int ima_appraise_measurement(enum ima_hooks func,
status = INTEGRITY_FAIL;
break;
}
+ clear_bit(IMA_DIGSIG, &iint->atomic_flags);
if (xattr_len - sizeof(xattr_value->type) - hash_start >=
iint->ima_hash->length)
/* xattr length may be longer. md5 hash in previous
@@ -269,7 +270,7 @@ int ima_appraise_measurement(enum ima_hooks func,
status = INTEGRITY_PASS;
break;
case EVM_IMA_XATTR_DIGSIG:
- iint->flags |= IMA_DIGSIG;
+ set_bit(IMA_DIGSIG, &iint->atomic_flags);
rc = integrity_digsig_verify(INTEGRITY_KEYRING_IMA,
(const char *)xattr_value, rc,
iint->ima_hash->digest,
@@ -320,7 +321,7 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
int rc = 0;
/* do not collect and update hash for digital signatures */
- if (iint->flags & IMA_DIGSIG)
+ if (test_bit(IMA_DIGSIG, &iint->atomic_flags))
return;
if (iint->ima_file_status != INTEGRITY_PASS)
@@ -330,7 +331,9 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
if (rc < 0)
return;
+ inode_lock(file_inode(file));
ima_fix_xattr(dentry, iint);
+ inode_unlock(file_inode(file));
}
/**
@@ -353,16 +356,14 @@ void ima_inode_post_setattr(struct dentry *dentry)
return;
must_appraise = ima_must_appraise(inode, MAY_ACCESS, POST_SETATTR);
+ if (!must_appraise)
+ __vfs_removexattr(dentry, XATTR_NAME_IMA);
iint = integrity_iint_find(inode);
if (iint) {
- iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED |
- IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK |
- IMA_ACTION_RULE_FLAGS);
- if (must_appraise)
- iint->flags |= IMA_APPRAISE;
+ set_bit(IMA_CHANGE_ATTR, &iint->atomic_flags);
+ if (!must_appraise)
+ clear_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
}
- if (!must_appraise)
- __vfs_removexattr(dentry, XATTR_NAME_IMA);
}
/*
@@ -391,12 +392,12 @@ static void ima_reset_appraise_flags(struct inode *inode, int digsig)
iint = integrity_iint_find(inode);
if (!iint)
return;
-
- iint->flags &= ~IMA_DONE_MASK;
iint->measured_pcrs = 0;
+ set_bit(IMA_CHANGE_XATTR, &iint->atomic_flags);
if (digsig)
- iint->flags |= IMA_DIGSIG;
- return;
+ set_bit(IMA_DIGSIG, &iint->atomic_flags);
+ else
+ clear_bit(IMA_DIGSIG, &iint->atomic_flags);
}
int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 06c4cf125f2a..92d0ca7309f9 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -99,10 +99,13 @@ static void ima_rdwr_violation_check(struct file *file,
if (!iint)
iint = integrity_iint_find(inode);
/* IMA_MEASURE is set from reader side */
- if (iint && (iint->flags & IMA_MEASURE))
+ if (iint && test_bit(IMA_MUST_MEASURE,
+ &iint->atomic_flags))
send_tomtou = true;
}
} else {
+ if (must_measure)
+ set_bit(IMA_MUST_MEASURE, &iint->atomic_flags);
if ((atomic_read(&inode->i_writecount) > 0) && must_measure)
send_writers = true;
}
@@ -124,21 +127,24 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint,
struct inode *inode, struct file *file)
{
fmode_t mode = file->f_mode;
+ bool update;
if (!(mode & FMODE_WRITE))
return;
- inode_lock(inode);
+ mutex_lock(&iint->mutex);
if (atomic_read(&inode->i_writecount) == 1) {
+ update = test_and_clear_bit(IMA_UPDATE_XATTR,
+ &iint->atomic_flags);
if ((iint->version != inode->i_version) ||
(iint->flags & IMA_NEW_FILE)) {
iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE);
iint->measured_pcrs = 0;
- if (iint->flags & IMA_APPRAISE)
+ if (update)
ima_update_xattr(iint, file);
}
}
- inode_unlock(inode);
+ mutex_unlock(&iint->mutex);
}
/**
@@ -171,7 +177,7 @@ static int process_measurement(struct file *file, char *buf, loff_t size,
char *pathbuf = NULL;
char filename[NAME_MAX];
const char *pathname = NULL;
- int rc = -ENOMEM, action, must_appraise;
+ int rc = 0, action, must_appraise = 0;
int pcr = CONFIG_IMA_MEASURE_PCR_IDX;
struct evm_ima_xattr_data *xattr_value = NULL;
int xattr_len = 0;
@@ -202,17 +208,31 @@ static int process_measurement(struct file *file, char *buf, loff_t size,
if (action) {
iint = integrity_inode_get(inode);
if (!iint)
- goto out;
+ rc = -ENOMEM;
}
- if (violation_check) {
+ if (!rc && violation_check)
ima_rdwr_violation_check(file, iint, action & IMA_MEASURE,
&pathbuf, &pathname);
- if (!action) {
- rc = 0;
- goto out_free;
- }
- }
+
+ inode_unlock(inode);
+
+ if (rc)
+ goto out;
+ if (!action)
+ goto out;
+
+ mutex_lock(&iint->mutex);
+
+ if (test_and_clear_bit(IMA_CHANGE_ATTR, &iint->atomic_flags))
+ /* reset appraisal flags if ima_inode_post_setattr was called */
+ iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED |
+ IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK |
+ IMA_ACTION_FLAGS);
+
+ if (test_and_clear_bit(IMA_CHANGE_XATTR, &iint->atomic_flags))
+ /* reset all flags if ima_inode_setxattr was called */
+ iint->flags &= ~IMA_DONE_MASK;
/* Determine if already appraised/measured based on bitmask
* (IMA_MEASURE, IMA_MEASURED, IMA_XXXX_APPRAISE, IMA_XXXX_APPRAISED,
@@ -230,7 +250,7 @@ static int process_measurement(struct file *file, char *buf, loff_t size,
if (!action) {
if (must_appraise)
rc = ima_get_cache_status(iint, func);
- goto out_digsig;
+ goto out_locked;
}
template_desc = ima_template_desc_current();
@@ -243,7 +263,7 @@ static int process_measurement(struct file *file, char *buf, loff_t size,
rc = ima_collect_measurement(iint, file, buf, size, hash_algo);
if (rc != 0 && rc != -EBADF && rc != -EINVAL)
- goto out_digsig;
+ goto out_locked;
if (!pathbuf) /* ima_rdwr_violation possibly pre-fetched */
pathname = ima_d_path(&file->f_path, &pathbuf, filename);
@@ -251,26 +271,32 @@ static int process_measurement(struct file *file, char *buf, loff_t size,
if (action & IMA_MEASURE)
ima_store_measurement(iint, file, pathname,
xattr_value, xattr_len, pcr);
- if (rc == 0 && (action & IMA_APPRAISE_SUBMASK))
+ if (rc == 0 && (action & IMA_APPRAISE_SUBMASK)) {
+ inode_lock(inode);
rc = ima_appraise_measurement(func, iint, file, pathname,
xattr_value, xattr_len, opened);
+ inode_unlock(inode);
+ }
if (action & IMA_AUDIT)
ima_audit_measurement(iint, pathname);
if ((file->f_flags & O_DIRECT) && (iint->flags & IMA_PERMIT_DIRECTIO))
rc = 0;
-out_digsig:
- if ((mask & MAY_WRITE) && (iint->flags & IMA_DIGSIG) &&
+out_locked:
+ if ((mask & MAY_WRITE) && test_bit(IMA_DIGSIG, &iint->atomic_flags) &&
!(iint->flags & IMA_NEW_FILE))
rc = -EACCES;
+ mutex_unlock(&iint->mutex);
kfree(xattr_value);
-out_free:
+out:
if (pathbuf)
__putname(pathbuf);
-out:
- inode_unlock(inode);
- if ((rc && must_appraise) && (ima_appraise & IMA_APPRAISE_ENFORCE))
- return -EACCES;
+ if (must_appraise) {
+ if (rc && (ima_appraise & IMA_APPRAISE_ENFORCE))
+ return -EACCES;
+ if (file->f_mode & FMODE_WRITE)
+ set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
+ }
return 0;
}
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
index cbc7de33fac7..f43ac351c172 100644
--- a/security/integrity/integrity.h
+++ b/security/integrity/integrity.h
@@ -29,11 +29,10 @@
/* iint cache flags */
#define IMA_ACTION_FLAGS 0xff000000
#define IMA_ACTION_RULE_FLAGS 0x06000000
-#define IMA_DIGSIG 0x01000000
-#define IMA_DIGSIG_REQUIRED 0x02000000
-#define IMA_PERMIT_DIRECTIO 0x04000000
-#define IMA_NEW_FILE 0x08000000
-#define EVM_IMMUTABLE_DIGSIG 0x10000000
+#define IMA_DIGSIG_REQUIRED 0x01000000
+#define IMA_PERMIT_DIRECTIO 0x02000000
+#define IMA_NEW_FILE 0x04000000
+#define EVM_IMMUTABLE_DIGSIG 0x08000000
#define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
IMA_APPRAISE_SUBMASK)
@@ -54,6 +53,13 @@
#define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
IMA_BPRM_APPRAISED | IMA_READ_APPRAISED)
+/* iint cache atomic_flags */
+#define IMA_CHANGE_XATTR 0
+#define IMA_UPDATE_XATTR 1
+#define IMA_CHANGE_ATTR 2
+#define IMA_DIGSIG 3
+#define IMA_MUST_MEASURE 4
+
enum evm_ima_xattr_type {
IMA_XATTR_DIGEST = 0x01,
EVM_XATTR_HMAC,
@@ -102,10 +108,12 @@ struct signature_v2_hdr {
/* integrity data associated with an inode */
struct integrity_iint_cache {
struct rb_node rb_node; /* rooted in integrity_iint_tree */
+ struct mutex mutex; /* protects: version, flags, digest */
struct inode *inode; /* back pointer to inode in question */
u64 version; /* track inode changes */
unsigned long flags;
unsigned long measured_pcrs;
+ unsigned long atomic_flags;
enum integrity_status ima_file_status:4;
enum integrity_status ima_mmap_status:4;
enum integrity_status ima_bprm_status:4;