diff options
Diffstat (limited to 'security/integrity/evm/evm_main.c')
| -rw-r--r-- | security/integrity/evm/evm_main.c | 76 |
1 files changed, 56 insertions, 20 deletions
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index 0a089af83a45..81dbade5b9b3 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -178,14 +178,14 @@ static int is_unsupported_fs(struct dentry *dentry) static enum integrity_status evm_verify_hmac(struct dentry *dentry, const char *xattr_name, char *xattr_value, - size_t xattr_value_len, - struct integrity_iint_cache *iint) + size_t xattr_value_len) { struct evm_ima_xattr_data *xattr_data = NULL; struct signature_v2_hdr *hdr; enum integrity_status evm_status = INTEGRITY_PASS; struct evm_digest digest; - struct inode *inode; + struct inode *inode = d_backing_inode(dentry); + struct evm_iint_cache *iint = evm_iint_inode(inode); int rc, xattr_len, evm_immutable = 0; if (iint && (iint->evm_status == INTEGRITY_PASS || @@ -254,8 +254,6 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry, (const char *)xattr_data, xattr_len, digest.digest, digest.hdr.length); if (!rc) { - inode = d_backing_inode(dentry); - if (xattr_data->type == EVM_XATTR_PORTABLE_DIGSIG) { if (iint) iint->flags |= EVM_IMMUTABLE_DIGSIG; @@ -403,7 +401,6 @@ int evm_read_protected_xattrs(struct dentry *dentry, u8 *buffer, * @xattr_name: requested xattr * @xattr_value: requested xattr value * @xattr_value_len: requested xattr value length - * @iint: inode integrity metadata * * Calculate the HMAC for the given dentry and verify it against the stored * security.evm xattr. For performance, use the xattr value and length @@ -416,8 +413,7 @@ int evm_read_protected_xattrs(struct dentry *dentry, u8 *buffer, */ enum integrity_status evm_verifyxattr(struct dentry *dentry, const char *xattr_name, - void *xattr_value, size_t xattr_value_len, - struct integrity_iint_cache *iint) + void *xattr_value, size_t xattr_value_len) { if (!evm_key_loaded() || !evm_protected_xattr(xattr_name)) return INTEGRITY_UNKNOWN; @@ -425,13 +421,8 @@ enum integrity_status evm_verifyxattr(struct dentry *dentry, if (is_unsupported_fs(dentry)) return INTEGRITY_UNKNOWN; - if (!iint) { - iint = integrity_iint_find(d_backing_inode(dentry)); - if (!iint) - return INTEGRITY_UNKNOWN; - } return evm_verify_hmac(dentry, xattr_name, xattr_value, - xattr_value_len, iint); + xattr_value_len); } EXPORT_SYMBOL_GPL(evm_verifyxattr); @@ -448,7 +439,7 @@ static enum integrity_status evm_verify_current_integrity(struct dentry *dentry) if (!evm_key_loaded() || !S_ISREG(inode->i_mode) || evm_fixmode) return INTEGRITY_PASS; - return evm_verify_hmac(dentry, NULL, NULL, 0, NULL); + return evm_verify_hmac(dentry, NULL, NULL, 0); } /* @@ -526,14 +517,14 @@ static int evm_protect_xattr(struct mnt_idmap *idmap, evm_status = evm_verify_current_integrity(dentry); if (evm_status == INTEGRITY_NOXATTRS) { - struct integrity_iint_cache *iint; + struct evm_iint_cache *iint; /* Exception if the HMAC is not going to be calculated. */ if (evm_hmac_disabled()) return 0; - iint = integrity_iint_find(d_backing_inode(dentry)); - if (iint && (iint->flags & IMA_NEW_FILE)) + iint = evm_iint_inode(d_backing_inode(dentry)); + if (iint && (iint->flags & EVM_NEW_FILE)) return 0; /* exception for pseudo filesystems */ @@ -735,9 +726,9 @@ static int evm_inode_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry, static void evm_reset_status(struct inode *inode) { - struct integrity_iint_cache *iint; + struct evm_iint_cache *iint; - iint = integrity_iint_find(inode); + iint = evm_iint_inode(inode); if (iint) iint->evm_status = INTEGRITY_UNKNOWN; } @@ -1019,6 +1010,42 @@ out: } EXPORT_SYMBOL_GPL(evm_inode_init_security); +static int evm_inode_alloc_security(struct inode *inode) +{ + struct evm_iint_cache *iint = evm_iint_inode(inode); + + /* Called by security_inode_alloc(), it cannot be NULL. */ + iint->flags = 0UL; + iint->evm_status = INTEGRITY_UNKNOWN; + + return 0; +} + +static void evm_file_release(struct file *file) +{ + struct inode *inode = file_inode(file); + struct evm_iint_cache *iint = evm_iint_inode(inode); + fmode_t mode = file->f_mode; + + if (!S_ISREG(inode->i_mode) || !(mode & FMODE_WRITE)) + return; + + if (iint && atomic_read(&inode->i_writecount) == 1) + iint->flags &= ~EVM_NEW_FILE; +} + +static void evm_post_path_mknod(struct mnt_idmap *idmap, struct dentry *dentry) +{ + struct inode *inode = d_backing_inode(dentry); + struct evm_iint_cache *iint = evm_iint_inode(inode); + + if (!S_ISREG(inode->i_mode)) + return; + + if (iint) + iint->flags |= EVM_NEW_FILE; +} + #ifdef CONFIG_EVM_LOAD_X509 void __init evm_load_x509(void) { @@ -1071,6 +1098,9 @@ static struct security_hook_list evm_hooks[] __ro_after_init = { LSM_HOOK_INIT(inode_removexattr, evm_inode_removexattr), LSM_HOOK_INIT(inode_post_removexattr, evm_inode_post_removexattr), LSM_HOOK_INIT(inode_init_security, evm_inode_init_security), + LSM_HOOK_INIT(inode_alloc_security, evm_inode_alloc_security), + LSM_HOOK_INIT(file_release, evm_file_release), + LSM_HOOK_INIT(path_post_mknod, evm_post_path_mknod), }; static const struct lsm_id evm_lsmid = { @@ -1084,10 +1114,16 @@ static int __init init_evm_lsm(void) return 0; } +struct lsm_blob_sizes evm_blob_sizes __ro_after_init = { + .lbs_inode = sizeof(struct evm_iint_cache), + .lbs_xattr_count = 1, +}; + DEFINE_LSM(evm) = { .name = "evm", .init = init_evm_lsm, .order = LSM_ORDER_LAST, + .blobs = &evm_blob_sizes, }; late_initcall(init_evm); |