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- // SPDX-License-Identifier: GPL-2.0-only
- /*
- * Copyright (C) 2011 IBM Corporation
- *
- * Author:
- * Mimi Zohar <[email protected]>
- */
- #include <linux/module.h>
- #include <linux/init.h>
- #include <linux/file.h>
- #include <linux/fs.h>
- #include <linux/xattr.h>
- #include <linux/magic.h>
- #include <linux/ima.h>
- #include <linux/evm.h>
- #include <linux/fsverity.h>
- #include <keys/system_keyring.h>
- #include <uapi/linux/fsverity.h>
- #include "ima.h"
- #ifdef CONFIG_IMA_APPRAISE_BOOTPARAM
- static char *ima_appraise_cmdline_default __initdata;
- core_param(ima_appraise, ima_appraise_cmdline_default, charp, 0);
- void __init ima_appraise_parse_cmdline(void)
- {
- const char *str = ima_appraise_cmdline_default;
- bool sb_state = arch_ima_get_secureboot();
- int appraisal_state = ima_appraise;
- if (!str)
- return;
- if (strncmp(str, "off", 3) == 0)
- appraisal_state = 0;
- else if (strncmp(str, "log", 3) == 0)
- appraisal_state = IMA_APPRAISE_LOG;
- else if (strncmp(str, "fix", 3) == 0)
- appraisal_state = IMA_APPRAISE_FIX;
- else if (strncmp(str, "enforce", 7) == 0)
- appraisal_state = IMA_APPRAISE_ENFORCE;
- else
- pr_err("invalid \"%s\" appraise option", str);
- /* If appraisal state was changed, but secure boot is enabled,
- * keep its default */
- if (sb_state) {
- if (!(appraisal_state & IMA_APPRAISE_ENFORCE))
- pr_info("Secure boot enabled: ignoring ima_appraise=%s option",
- str);
- } else {
- ima_appraise = appraisal_state;
- }
- }
- #endif
- /*
- * is_ima_appraise_enabled - return appraise status
- *
- * Only return enabled, if not in ima_appraise="fix" or "log" modes.
- */
- bool is_ima_appraise_enabled(void)
- {
- return ima_appraise & IMA_APPRAISE_ENFORCE;
- }
- /*
- * ima_must_appraise - set appraise flag
- *
- * Return 1 to appraise or hash
- */
- int ima_must_appraise(struct user_namespace *mnt_userns, struct inode *inode,
- int mask, enum ima_hooks func)
- {
- u32 secid;
- if (!ima_appraise)
- return 0;
- security_current_getsecid_subj(&secid);
- return ima_match_policy(mnt_userns, inode, current_cred(), secid,
- func, mask, IMA_APPRAISE | IMA_HASH, NULL,
- NULL, NULL, NULL);
- }
- static int ima_fix_xattr(struct dentry *dentry,
- struct integrity_iint_cache *iint)
- {
- int rc, offset;
- u8 algo = iint->ima_hash->algo;
- if (algo <= HASH_ALGO_SHA1) {
- offset = 1;
- iint->ima_hash->xattr.sha1.type = IMA_XATTR_DIGEST;
- } else {
- offset = 0;
- iint->ima_hash->xattr.ng.type = IMA_XATTR_DIGEST_NG;
- iint->ima_hash->xattr.ng.algo = algo;
- }
- rc = __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_IMA,
- &iint->ima_hash->xattr.data[offset],
- (sizeof(iint->ima_hash->xattr) - offset) +
- iint->ima_hash->length, 0);
- return rc;
- }
- /* Return specific func appraised cached result */
- enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
- enum ima_hooks func)
- {
- switch (func) {
- case MMAP_CHECK:
- return iint->ima_mmap_status;
- case BPRM_CHECK:
- return iint->ima_bprm_status;
- case CREDS_CHECK:
- return iint->ima_creds_status;
- case FILE_CHECK:
- case POST_SETATTR:
- return iint->ima_file_status;
- case MODULE_CHECK ... MAX_CHECK - 1:
- default:
- return iint->ima_read_status;
- }
- }
- static void ima_set_cache_status(struct integrity_iint_cache *iint,
- enum ima_hooks func,
- enum integrity_status status)
- {
- switch (func) {
- case MMAP_CHECK:
- iint->ima_mmap_status = status;
- break;
- case BPRM_CHECK:
- iint->ima_bprm_status = status;
- break;
- case CREDS_CHECK:
- iint->ima_creds_status = status;
- break;
- case FILE_CHECK:
- case POST_SETATTR:
- iint->ima_file_status = status;
- break;
- case MODULE_CHECK ... MAX_CHECK - 1:
- default:
- iint->ima_read_status = status;
- break;
- }
- }
- static void ima_cache_flags(struct integrity_iint_cache *iint,
- enum ima_hooks func)
- {
- switch (func) {
- case MMAP_CHECK:
- iint->flags |= (IMA_MMAP_APPRAISED | IMA_APPRAISED);
- break;
- case BPRM_CHECK:
- iint->flags |= (IMA_BPRM_APPRAISED | IMA_APPRAISED);
- break;
- case CREDS_CHECK:
- iint->flags |= (IMA_CREDS_APPRAISED | IMA_APPRAISED);
- break;
- case FILE_CHECK:
- case POST_SETATTR:
- iint->flags |= (IMA_FILE_APPRAISED | IMA_APPRAISED);
- break;
- case MODULE_CHECK ... MAX_CHECK - 1:
- default:
- iint->flags |= (IMA_READ_APPRAISED | IMA_APPRAISED);
- break;
- }
- }
- enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value,
- int xattr_len)
- {
- struct signature_v2_hdr *sig;
- enum hash_algo ret;
- if (!xattr_value || xattr_len < 2)
- /* return default hash algo */
- return ima_hash_algo;
- switch (xattr_value->type) {
- case IMA_VERITY_DIGSIG:
- sig = (typeof(sig))xattr_value;
- if (sig->version != 3 || xattr_len <= sizeof(*sig) ||
- sig->hash_algo >= HASH_ALGO__LAST)
- return ima_hash_algo;
- return sig->hash_algo;
- case EVM_IMA_XATTR_DIGSIG:
- sig = (typeof(sig))xattr_value;
- if (sig->version != 2 || xattr_len <= sizeof(*sig)
- || sig->hash_algo >= HASH_ALGO__LAST)
- return ima_hash_algo;
- return sig->hash_algo;
- case IMA_XATTR_DIGEST_NG:
- /* first byte contains algorithm id */
- ret = xattr_value->data[0];
- if (ret < HASH_ALGO__LAST)
- return ret;
- break;
- case IMA_XATTR_DIGEST:
- /* this is for backward compatibility */
- if (xattr_len == 21) {
- unsigned int zero = 0;
- if (!memcmp(&xattr_value->data[16], &zero, 4))
- return HASH_ALGO_MD5;
- else
- return HASH_ALGO_SHA1;
- } else if (xattr_len == 17)
- return HASH_ALGO_MD5;
- break;
- }
- /* return default hash algo */
- return ima_hash_algo;
- }
- int ima_read_xattr(struct dentry *dentry,
- struct evm_ima_xattr_data **xattr_value)
- {
- ssize_t ret;
- ret = vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_IMA,
- (char **)xattr_value, 0, GFP_NOFS);
- if (ret == -EOPNOTSUPP)
- ret = 0;
- return ret;
- }
- /*
- * calc_file_id_hash - calculate the hash of the ima_file_id struct data
- * @type: xattr type [enum evm_ima_xattr_type]
- * @algo: hash algorithm [enum hash_algo]
- * @digest: pointer to the digest to be hashed
- * @hash: (out) pointer to the hash
- *
- * IMA signature version 3 disambiguates the data that is signed by
- * indirectly signing the hash of the ima_file_id structure data.
- *
- * Signing the ima_file_id struct is currently only supported for
- * IMA_VERITY_DIGSIG type xattrs.
- *
- * Return 0 on success, error code otherwise.
- */
- static int calc_file_id_hash(enum evm_ima_xattr_type type,
- enum hash_algo algo, const u8 *digest,
- struct ima_digest_data *hash)
- {
- struct ima_file_id file_id = {
- .hash_type = IMA_VERITY_DIGSIG, .hash_algorithm = algo};
- unsigned int unused = HASH_MAX_DIGESTSIZE - hash_digest_size[algo];
- if (type != IMA_VERITY_DIGSIG)
- return -EINVAL;
- memcpy(file_id.hash, digest, hash_digest_size[algo]);
- hash->algo = algo;
- hash->length = hash_digest_size[algo];
- return ima_calc_buffer_hash(&file_id, sizeof(file_id) - unused, hash);
- }
- /*
- * xattr_verify - verify xattr digest or signature
- *
- * Verify whether the hash or signature matches the file contents.
- *
- * Return 0 on success, error code otherwise.
- */
- static int xattr_verify(enum ima_hooks func, struct integrity_iint_cache *iint,
- struct evm_ima_xattr_data *xattr_value, int xattr_len,
- enum integrity_status *status, const char **cause)
- {
- struct ima_max_digest_data hash;
- struct signature_v2_hdr *sig;
- int rc = -EINVAL, hash_start = 0;
- int mask;
- switch (xattr_value->type) {
- case IMA_XATTR_DIGEST_NG:
- /* first byte contains algorithm id */
- hash_start = 1;
- fallthrough;
- case IMA_XATTR_DIGEST:
- if (*status != INTEGRITY_PASS_IMMUTABLE) {
- if (iint->flags & IMA_DIGSIG_REQUIRED) {
- if (iint->flags & IMA_VERITY_REQUIRED)
- *cause = "verity-signature-required";
- else
- *cause = "IMA-signature-required";
- *status = INTEGRITY_FAIL;
- break;
- }
- clear_bit(IMA_DIGSIG, &iint->atomic_flags);
- } else {
- set_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
- * version occupied 20 bytes in xattr, instead of 16
- */
- rc = memcmp(&xattr_value->data[hash_start],
- iint->ima_hash->digest,
- iint->ima_hash->length);
- else
- rc = -EINVAL;
- if (rc) {
- *cause = "invalid-hash";
- *status = INTEGRITY_FAIL;
- break;
- }
- *status = INTEGRITY_PASS;
- break;
- case EVM_IMA_XATTR_DIGSIG:
- set_bit(IMA_DIGSIG, &iint->atomic_flags);
- mask = IMA_DIGSIG_REQUIRED | IMA_VERITY_REQUIRED;
- if ((iint->flags & mask) == mask) {
- *cause = "verity-signature-required";
- *status = INTEGRITY_FAIL;
- break;
- }
- sig = (typeof(sig))xattr_value;
- if (sig->version >= 3) {
- *cause = "invalid-signature-version";
- *status = INTEGRITY_FAIL;
- break;
- }
- rc = integrity_digsig_verify(INTEGRITY_KEYRING_IMA,
- (const char *)xattr_value,
- xattr_len,
- iint->ima_hash->digest,
- iint->ima_hash->length);
- if (rc == -EOPNOTSUPP) {
- *status = INTEGRITY_UNKNOWN;
- break;
- }
- if (IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING) && rc &&
- func == KEXEC_KERNEL_CHECK)
- rc = integrity_digsig_verify(INTEGRITY_KEYRING_PLATFORM,
- (const char *)xattr_value,
- xattr_len,
- iint->ima_hash->digest,
- iint->ima_hash->length);
- if (rc) {
- *cause = "invalid-signature";
- *status = INTEGRITY_FAIL;
- } else {
- *status = INTEGRITY_PASS;
- }
- break;
- case IMA_VERITY_DIGSIG:
- set_bit(IMA_DIGSIG, &iint->atomic_flags);
- if (iint->flags & IMA_DIGSIG_REQUIRED) {
- if (!(iint->flags & IMA_VERITY_REQUIRED)) {
- *cause = "IMA-signature-required";
- *status = INTEGRITY_FAIL;
- break;
- }
- }
- sig = (typeof(sig))xattr_value;
- if (sig->version != 3) {
- *cause = "invalid-signature-version";
- *status = INTEGRITY_FAIL;
- break;
- }
- rc = calc_file_id_hash(IMA_VERITY_DIGSIG, iint->ima_hash->algo,
- iint->ima_hash->digest, &hash.hdr);
- if (rc) {
- *cause = "sigv3-hashing-error";
- *status = INTEGRITY_FAIL;
- break;
- }
- rc = integrity_digsig_verify(INTEGRITY_KEYRING_IMA,
- (const char *)xattr_value,
- xattr_len, hash.digest,
- hash.hdr.length);
- if (rc) {
- *cause = "invalid-verity-signature";
- *status = INTEGRITY_FAIL;
- } else {
- *status = INTEGRITY_PASS;
- }
- break;
- default:
- *status = INTEGRITY_UNKNOWN;
- *cause = "unknown-ima-data";
- break;
- }
- return rc;
- }
- /*
- * modsig_verify - verify modsig signature
- *
- * Verify whether the signature matches the file contents.
- *
- * Return 0 on success, error code otherwise.
- */
- static int modsig_verify(enum ima_hooks func, const struct modsig *modsig,
- enum integrity_status *status, const char **cause)
- {
- int rc;
- rc = integrity_modsig_verify(INTEGRITY_KEYRING_IMA, modsig);
- if (IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING) && rc &&
- func == KEXEC_KERNEL_CHECK)
- rc = integrity_modsig_verify(INTEGRITY_KEYRING_PLATFORM,
- modsig);
- if (rc) {
- *cause = "invalid-signature";
- *status = INTEGRITY_FAIL;
- } else {
- *status = INTEGRITY_PASS;
- }
- return rc;
- }
- /*
- * ima_check_blacklist - determine if the binary is blacklisted.
- *
- * Add the hash of the blacklisted binary to the measurement list, based
- * on policy.
- *
- * Returns -EPERM if the hash is blacklisted.
- */
- int ima_check_blacklist(struct integrity_iint_cache *iint,
- const struct modsig *modsig, int pcr)
- {
- enum hash_algo hash_algo;
- const u8 *digest = NULL;
- u32 digestsize = 0;
- int rc = 0;
- if (!(iint->flags & IMA_CHECK_BLACKLIST))
- return 0;
- if (iint->flags & IMA_MODSIG_ALLOWED && modsig) {
- ima_get_modsig_digest(modsig, &hash_algo, &digest, &digestsize);
- rc = is_binary_blacklisted(digest, digestsize);
- if ((rc == -EPERM) && (iint->flags & IMA_MEASURE))
- process_buffer_measurement(&init_user_ns, NULL, digest, digestsize,
- "blacklisted-hash", NONE,
- pcr, NULL, false, NULL, 0);
- }
- return rc;
- }
- /*
- * ima_appraise_measurement - appraise file measurement
- *
- * Call evm_verifyxattr() to verify the integrity of 'security.ima'.
- * Assuming success, compare the xattr hash with the collected measurement.
- *
- * Return 0 on success, error code otherwise
- */
- int ima_appraise_measurement(enum ima_hooks func,
- struct integrity_iint_cache *iint,
- struct file *file, const unsigned char *filename,
- struct evm_ima_xattr_data *xattr_value,
- int xattr_len, const struct modsig *modsig)
- {
- static const char op[] = "appraise_data";
- const char *cause = "unknown";
- struct dentry *dentry = file_dentry(file);
- struct inode *inode = d_backing_inode(dentry);
- enum integrity_status status = INTEGRITY_UNKNOWN;
- int rc = xattr_len;
- bool try_modsig = iint->flags & IMA_MODSIG_ALLOWED && modsig;
- /* If not appraising a modsig, we need an xattr. */
- if (!(inode->i_opflags & IOP_XATTR) && !try_modsig)
- return INTEGRITY_UNKNOWN;
- /* If reading the xattr failed and there's no modsig, error out. */
- if (rc <= 0 && !try_modsig) {
- if (rc && rc != -ENODATA)
- goto out;
- if (iint->flags & IMA_DIGSIG_REQUIRED) {
- if (iint->flags & IMA_VERITY_REQUIRED)
- cause = "verity-signature-required";
- else
- cause = "IMA-signature-required";
- } else {
- cause = "missing-hash";
- }
- status = INTEGRITY_NOLABEL;
- if (file->f_mode & FMODE_CREATED)
- iint->flags |= IMA_NEW_FILE;
- if ((iint->flags & IMA_NEW_FILE) &&
- (!(iint->flags & IMA_DIGSIG_REQUIRED) ||
- (inode->i_size == 0)))
- status = INTEGRITY_PASS;
- goto out;
- }
- status = evm_verifyxattr(dentry, XATTR_NAME_IMA, xattr_value,
- rc < 0 ? 0 : rc, iint);
- switch (status) {
- case INTEGRITY_PASS:
- case INTEGRITY_PASS_IMMUTABLE:
- case INTEGRITY_UNKNOWN:
- break;
- case INTEGRITY_NOXATTRS: /* No EVM protected xattrs. */
- /* It's fine not to have xattrs when using a modsig. */
- if (try_modsig)
- break;
- fallthrough;
- case INTEGRITY_NOLABEL: /* No security.evm xattr. */
- cause = "missing-HMAC";
- goto out;
- case INTEGRITY_FAIL_IMMUTABLE:
- set_bit(IMA_DIGSIG, &iint->atomic_flags);
- cause = "invalid-fail-immutable";
- goto out;
- case INTEGRITY_FAIL: /* Invalid HMAC/signature. */
- cause = "invalid-HMAC";
- goto out;
- default:
- WARN_ONCE(true, "Unexpected integrity status %d\n", status);
- }
- if (xattr_value)
- rc = xattr_verify(func, iint, xattr_value, xattr_len, &status,
- &cause);
- /*
- * If we have a modsig and either no imasig or the imasig's key isn't
- * known, then try verifying the modsig.
- */
- if (try_modsig &&
- (!xattr_value || xattr_value->type == IMA_XATTR_DIGEST_NG ||
- rc == -ENOKEY))
- rc = modsig_verify(func, modsig, &status, &cause);
- out:
- /*
- * File signatures on some filesystems can not be properly verified.
- * When such filesystems are mounted by an untrusted mounter or on a
- * system not willing to accept such a risk, fail the file signature
- * verification.
- */
- if ((inode->i_sb->s_iflags & SB_I_IMA_UNVERIFIABLE_SIGNATURE) &&
- ((inode->i_sb->s_iflags & SB_I_UNTRUSTED_MOUNTER) ||
- (iint->flags & IMA_FAIL_UNVERIFIABLE_SIGS))) {
- status = INTEGRITY_FAIL;
- cause = "unverifiable-signature";
- integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, filename,
- op, cause, rc, 0);
- } else if (status != INTEGRITY_PASS) {
- /* Fix mode, but don't replace file signatures. */
- if ((ima_appraise & IMA_APPRAISE_FIX) && !try_modsig &&
- (!xattr_value ||
- xattr_value->type != EVM_IMA_XATTR_DIGSIG)) {
- if (!ima_fix_xattr(dentry, iint))
- status = INTEGRITY_PASS;
- }
- /*
- * Permit new files with file/EVM portable signatures, but
- * without data.
- */
- if (inode->i_size == 0 && iint->flags & IMA_NEW_FILE &&
- test_bit(IMA_DIGSIG, &iint->atomic_flags)) {
- status = INTEGRITY_PASS;
- }
- integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, filename,
- op, cause, rc, 0);
- } else {
- ima_cache_flags(iint, func);
- }
- ima_set_cache_status(iint, func, status);
- return status;
- }
- /*
- * ima_update_xattr - update 'security.ima' hash value
- */
- void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
- {
- struct dentry *dentry = file_dentry(file);
- int rc = 0;
- /* do not collect and update hash for digital signatures */
- if (test_bit(IMA_DIGSIG, &iint->atomic_flags))
- return;
- if ((iint->ima_file_status != INTEGRITY_PASS) &&
- !(iint->flags & IMA_HASH))
- return;
- rc = ima_collect_measurement(iint, file, NULL, 0, ima_hash_algo, NULL);
- if (rc < 0)
- return;
- inode_lock(file_inode(file));
- ima_fix_xattr(dentry, iint);
- inode_unlock(file_inode(file));
- }
- /**
- * ima_inode_post_setattr - reflect file metadata changes
- * @mnt_userns: user namespace of the mount the inode was found from
- * @dentry: pointer to the affected dentry
- *
- * Changes to a dentry's metadata might result in needing to appraise.
- *
- * This function is called from notify_change(), which expects the caller
- * to lock the inode's i_mutex.
- */
- void ima_inode_post_setattr(struct user_namespace *mnt_userns,
- struct dentry *dentry)
- {
- struct inode *inode = d_backing_inode(dentry);
- struct integrity_iint_cache *iint;
- int action;
- if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode)
- || !(inode->i_opflags & IOP_XATTR))
- return;
- action = ima_must_appraise(mnt_userns, 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);
- }
- }
- /*
- * ima_protect_xattr - protect 'security.ima'
- *
- * Ensure that not just anyone can modify or remove 'security.ima'.
- */
- static int ima_protect_xattr(struct dentry *dentry, const char *xattr_name,
- const void *xattr_value, size_t xattr_value_len)
- {
- if (strcmp(xattr_name, XATTR_NAME_IMA) == 0) {
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
- return 1;
- }
- return 0;
- }
- static void ima_reset_appraise_flags(struct inode *inode, int digsig)
- {
- struct integrity_iint_cache *iint;
- 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)
- set_bit(IMA_DIGSIG, &iint->atomic_flags);
- else
- clear_bit(IMA_DIGSIG, &iint->atomic_flags);
- }
- /**
- * validate_hash_algo() - Block setxattr with unsupported hash algorithms
- * @dentry: object of the setxattr()
- * @xattr_value: userland supplied xattr value
- * @xattr_value_len: length of xattr_value
- *
- * The xattr value is mapped to its hash algorithm, and this algorithm
- * must be built in the kernel for the setxattr to be allowed.
- *
- * Emit an audit message when the algorithm is invalid.
- *
- * Return: 0 on success, else an error.
- */
- static int validate_hash_algo(struct dentry *dentry,
- const struct evm_ima_xattr_data *xattr_value,
- size_t xattr_value_len)
- {
- char *path = NULL, *pathbuf = NULL;
- enum hash_algo xattr_hash_algo;
- const char *errmsg = "unavailable-hash-algorithm";
- unsigned int allowed_hashes;
- xattr_hash_algo = ima_get_hash_algo(xattr_value, xattr_value_len);
- allowed_hashes = atomic_read(&ima_setxattr_allowed_hash_algorithms);
- if (allowed_hashes) {
- /* success if the algorithm is allowed in the ima policy */
- if (allowed_hashes & (1U << xattr_hash_algo))
- return 0;
- /*
- * We use a different audit message when the hash algorithm
- * is denied by a policy rule, instead of not being built
- * in the kernel image
- */
- errmsg = "denied-hash-algorithm";
- } else {
- if (likely(xattr_hash_algo == ima_hash_algo))
- return 0;
- /* allow any xattr using an algorithm built in the kernel */
- if (crypto_has_alg(hash_algo_name[xattr_hash_algo], 0, 0))
- return 0;
- }
- pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
- if (!pathbuf)
- return -EACCES;
- path = dentry_path(dentry, pathbuf, PATH_MAX);
- integrity_audit_msg(AUDIT_INTEGRITY_DATA, d_inode(dentry), path,
- "set_data", errmsg, -EACCES, 0);
- kfree(pathbuf);
- return -EACCES;
- }
- int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
- const void *xattr_value, size_t xattr_value_len)
- {
- const struct evm_ima_xattr_data *xvalue = xattr_value;
- int digsig = 0;
- int result;
- int err;
- result = ima_protect_xattr(dentry, xattr_name, xattr_value,
- xattr_value_len);
- if (result == 1) {
- if (!xattr_value_len || (xvalue->type >= IMA_XATTR_LAST))
- return -EINVAL;
- err = validate_hash_algo(dentry, xvalue, xattr_value_len);
- if (err)
- return err;
- digsig = (xvalue->type == EVM_IMA_XATTR_DIGSIG);
- } else if (!strcmp(xattr_name, XATTR_NAME_EVM) && xattr_value_len > 0) {
- digsig = (xvalue->type == EVM_XATTR_PORTABLE_DIGSIG);
- }
- if (result == 1 || evm_revalidate_status(xattr_name)) {
- ima_reset_appraise_flags(d_backing_inode(dentry), digsig);
- if (result == 1)
- result = 0;
- }
- return result;
- }
- int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name)
- {
- int result;
- result = ima_protect_xattr(dentry, xattr_name, NULL, 0);
- if (result == 1 || evm_revalidate_status(xattr_name)) {
- ima_reset_appraise_flags(d_backing_inode(dentry), 0);
- if (result == 1)
- result = 0;
- }
- return result;
- }
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