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-rw-r--r--security/integrity/evm/evm_main.c22
-rw-r--r--security/integrity/ima/ima.h2
-rw-r--r--security/integrity/ima/ima_api.c10
-rw-r--r--security/integrity/ima/ima_appraise.c7
-rw-r--r--security/integrity/ima/ima_crypto.c32
-rw-r--r--security/integrity/ima/ima_fs.c2
-rw-r--r--security/integrity/ima/ima_main.c17
-rw-r--r--security/integrity/ima/ima_policy.c6
-rw-r--r--security/integrity/ima/ima_template_lib.c10
-rw-r--r--security/integrity/integrity.h2
10 files changed, 93 insertions, 17 deletions
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 336b3ddfe63f..7e71e066198f 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -269,6 +269,13 @@ static int evm_protect_xattr(struct dentry *dentry, const char *xattr_name,
goto out;
}
evm_status = evm_verify_current_integrity(dentry);
+ if (evm_status == INTEGRITY_NOXATTRS) {
+ struct integrity_iint_cache *iint;
+
+ iint = integrity_iint_find(dentry->d_inode);
+ if (iint && (iint->flags & IMA_NEW_FILE))
+ return 0;
+ }
out:
if (evm_status != INTEGRITY_PASS)
integrity_audit_msg(AUDIT_INTEGRITY_METADATA, dentry->d_inode,
@@ -285,12 +292,23 @@ out:
* @xattr_value: pointer to the new extended attribute value
* @xattr_value_len: pointer to the new extended attribute value length
*
- * Updating 'security.evm' requires CAP_SYS_ADMIN privileges and that
- * the current value is valid.
+ * Before allowing the 'security.evm' protected xattr to be updated,
+ * verify the existing value is valid. As only the kernel should have
+ * access to the EVM encrypted key needed to calculate the HMAC, prevent
+ * userspace from writing HMAC value. Writing 'security.evm' requires
+ * requires CAP_SYS_ADMIN privileges.
*/
int evm_inode_setxattr(struct dentry *dentry, const char *xattr_name,
const void *xattr_value, size_t xattr_value_len)
{
+ const struct evm_ima_xattr_data *xattr_data = xattr_value;
+
+ if (strcmp(xattr_name, XATTR_NAME_EVM) == 0) {
+ if (!xattr_value_len)
+ return -EINVAL;
+ if (xattr_data->type != EVM_IMA_XATTR_DIGSIG)
+ return -EPERM;
+ }
return evm_protect_xattr(dentry, xattr_name, xattr_value,
xattr_value_len);
}
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 0356e1d437ca..f79fa8be203c 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -27,7 +27,7 @@
#include "../integrity.h"
enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
- IMA_SHOW_ASCII };
+ IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
/* digest size for IMA, fits SHA1 or MD5 */
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index c38bbce8c6a6..025824af08e0 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -199,6 +199,7 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
struct evm_ima_xattr_data **xattr_value,
int *xattr_len)
{
+ const char *audit_cause = "failed";
struct inode *inode = file_inode(file);
const char *filename = file->f_dentry->d_name.name;
int result = 0;
@@ -213,6 +214,12 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
if (!(iint->flags & IMA_COLLECTED)) {
u64 i_version = file_inode(file)->i_version;
+ if (file->f_flags & O_DIRECT) {
+ audit_cause = "failed(directio)";
+ result = -EACCES;
+ goto out;
+ }
+
/* use default hash algorithm */
hash.hdr.algo = ima_hash_algo;
@@ -233,9 +240,10 @@ int ima_collect_measurement(struct integrity_iint_cache *iint,
result = -ENOMEM;
}
}
+out:
if (result)
integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode,
- filename, "collect_data", "failed",
+ filename, "collect_data", audit_cause,
result, 0);
return result;
}
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 734e9468aca0..6df1b2527d02 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -194,8 +194,11 @@ int ima_appraise_measurement(int func, struct integrity_iint_cache *iint,
goto out;
cause = "missing-hash";
- status =
- (inode->i_size == 0) ? INTEGRITY_PASS : INTEGRITY_NOLABEL;
+ status = INTEGRITY_NOLABEL;
+ if (inode->i_size == 0) {
+ iint->flags |= IMA_NEW_FILE;
+ status = INTEGRITY_PASS;
+ }
goto out;
}
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index fdf60def52e9..b5c126fe0bd9 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -25,6 +25,36 @@
static struct crypto_shash *ima_shash_tfm;
+/**
+ * ima_kernel_read - read file content
+ *
+ * This is a function for reading file content instead of kernel_read().
+ * It does not perform locking checks to ensure it cannot be blocked.
+ * It does not perform security checks because it is irrelevant for IMA.
+ *
+ */
+static int ima_kernel_read(struct file *file, loff_t offset,
+ char *addr, unsigned long count)
+{
+ mm_segment_t old_fs;
+ char __user *buf = addr;
+ ssize_t ret;
+
+ if (!(file->f_mode & FMODE_READ))
+ return -EBADF;
+ if (!file->f_op->read && !file->f_op->aio_read)
+ return -EINVAL;
+
+ old_fs = get_fs();
+ set_fs(get_ds());
+ if (file->f_op->read)
+ ret = file->f_op->read(file, buf, count, &offset);
+ else
+ ret = do_sync_read(file, buf, count, &offset);
+ set_fs(old_fs);
+ return ret;
+}
+
int ima_init_crypto(void)
{
long rc;
@@ -98,7 +128,7 @@ static int ima_calc_file_hash_tfm(struct file *file,
while (offset < i_size) {
int rbuf_len;
- rbuf_len = kernel_read(file, offset, rbuf, PAGE_SIZE);
+ rbuf_len = ima_kernel_read(file, offset, rbuf, PAGE_SIZE);
if (rbuf_len < 0) {
rc = rbuf_len;
break;
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index db01125926bd..468a3ba3c539 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c
@@ -160,6 +160,8 @@ static int ima_measurements_show(struct seq_file *m, void *v)
if (is_ima_template && strcmp(field->field_id, "d") == 0)
show = IMA_SHOW_BINARY_NO_FIELD_LEN;
+ if (is_ima_template && strcmp(field->field_id, "n") == 0)
+ show = IMA_SHOW_BINARY_OLD_STRING_FMT;
field->field_show(m, show, &e->template_data[i]);
}
return 0;
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 149ee1119f87..9f70efd08058 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -131,11 +131,13 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint,
return;
mutex_lock(&inode->i_mutex);
- if (atomic_read(&inode->i_writecount) == 1 &&
- iint->version != inode->i_version) {
- iint->flags &= ~IMA_DONE_MASK;
- if (iint->flags & IMA_APPRAISE)
- ima_update_xattr(iint, file);
+ if (atomic_read(&inode->i_writecount) == 1) {
+ if ((iint->version != inode->i_version) ||
+ (iint->flags & IMA_NEW_FILE)) {
+ iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE);
+ if (iint->flags & IMA_APPRAISE)
+ ima_update_xattr(iint, file);
+ }
}
mutex_unlock(&inode->i_mutex);
}
@@ -217,8 +219,11 @@ static int process_measurement(struct file *file, const char *filename,
xattr_ptr = &xattr_value;
rc = ima_collect_measurement(iint, file, xattr_ptr, &xattr_len);
- if (rc != 0)
+ if (rc != 0) {
+ if (file->f_flags & O_DIRECT)
+ rc = (iint->flags & IMA_PERMIT_DIRECTIO) ? 0 : -EACCES;
goto out_digsig;
+ }
pathname = !filename ? ima_d_path(&file->f_path, &pathbuf) : filename;
if (!pathname)
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index a9c3d3cd1990..085c4964be99 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -351,7 +351,7 @@ enum {
Opt_obj_user, Opt_obj_role, Opt_obj_type,
Opt_subj_user, Opt_subj_role, Opt_subj_type,
Opt_func, Opt_mask, Opt_fsmagic, Opt_uid, Opt_fowner,
- Opt_appraise_type, Opt_fsuuid
+ Opt_appraise_type, Opt_fsuuid, Opt_permit_directio
};
static match_table_t policy_tokens = {
@@ -373,6 +373,7 @@ static match_table_t policy_tokens = {
{Opt_uid, "uid=%s"},
{Opt_fowner, "fowner=%s"},
{Opt_appraise_type, "appraise_type=%s"},
+ {Opt_permit_directio, "permit_directio"},
{Opt_err, NULL}
};
@@ -621,6 +622,9 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
else
result = -EINVAL;
break;
+ case Opt_permit_directio:
+ entry->flags |= IMA_PERMIT_DIRECTIO;
+ break;
case Opt_err:
ima_log_string(ab, "UNKNOWN", p);
result = -EINVAL;
diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
index 1683bbf289a4..e8592e7bfc21 100644
--- a/security/integrity/ima/ima_template_lib.c
+++ b/security/integrity/ima/ima_template_lib.c
@@ -109,13 +109,16 @@ static void ima_show_template_data_binary(struct seq_file *m,
enum data_formats datafmt,
struct ima_field_data *field_data)
{
+ u32 len = (show == IMA_SHOW_BINARY_OLD_STRING_FMT) ?
+ strlen(field_data->data) : field_data->len;
+
if (show != IMA_SHOW_BINARY_NO_FIELD_LEN)
- ima_putc(m, &field_data->len, sizeof(u32));
+ ima_putc(m, &len, sizeof(len));
- if (!field_data->len)
+ if (!len)
return;
- ima_putc(m, field_data->data, field_data->len);
+ ima_putc(m, field_data->data, len);
}
static void ima_show_template_field_data(struct seq_file *m,
@@ -129,6 +132,7 @@ static void ima_show_template_field_data(struct seq_file *m,
break;
case IMA_SHOW_BINARY:
case IMA_SHOW_BINARY_NO_FIELD_LEN:
+ case IMA_SHOW_BINARY_OLD_STRING_FMT:
ima_show_template_data_binary(m, show, datafmt, field_data);
break;
default:
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
index 2fb5e53e927f..2f8715d77a5a 100644
--- a/security/integrity/integrity.h
+++ b/security/integrity/integrity.h
@@ -30,6 +30,8 @@
#define IMA_ACTION_FLAGS 0xff000000
#define IMA_DIGSIG 0x01000000
#define IMA_DIGSIG_REQUIRED 0x02000000
+#define IMA_PERMIT_DIRECTIO 0x04000000
+#define IMA_NEW_FILE 0x08000000
#define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
IMA_APPRAISE_SUBMASK)
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-06-04 12:42:02 +0000