diff options
| -rw-r--r-- | include/linux/fs.h | 1 | ||||
| -rw-r--r-- | security/integrity/evm/evm_main.c | 35 |
2 files changed, 35 insertions, 1 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index 98b7a7a8c42e..1474f36e9b38 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1164,6 +1164,7 @@ extern int send_sigurg(struct fown_struct *fown); #define SB_I_USERNS_VISIBLE 0x00000010 /* fstype already mounted */ #define SB_I_IMA_UNVERIFIABLE_SIGNATURE 0x00000020 #define SB_I_UNTRUSTED_MOUNTER 0x00000040 +#define SB_I_EVM_UNSUPPORTED 0x00000080 #define SB_I_SKIP_SYNC 0x00000100 /* Skip superblock at global sync */ #define SB_I_PERSB_BDI 0x00000200 /* has a per-sb bdi */ diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index 02adba635b02..cc7956d7878b 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -151,6 +151,17 @@ static int evm_find_protected_xattrs(struct dentry *dentry) return count; } +static int is_unsupported_fs(struct dentry *dentry) +{ + struct inode *inode = d_backing_inode(dentry); + + if (inode->i_sb->s_iflags & SB_I_EVM_UNSUPPORTED) { + pr_info_once("%s not supported\n", inode->i_sb->s_type->name); + return 1; + } + return 0; +} + /* * evm_verify_hmac - calculate and compare the HMAC with the EVM xattr * @@ -181,6 +192,9 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry, iint->evm_status == INTEGRITY_PASS_IMMUTABLE)) return iint->evm_status; + if (is_unsupported_fs(dentry)) + return INTEGRITY_UNKNOWN; + /* if status is not PASS, try to check again - against -ENOMEM */ /* first need to know the sig type */ @@ -408,6 +422,9 @@ enum integrity_status evm_verifyxattr(struct dentry *dentry, if (!evm_key_loaded() || !evm_protected_xattr(xattr_name)) return INTEGRITY_UNKNOWN; + if (is_unsupported_fs(dentry)) + return INTEGRITY_UNKNOWN; + if (!iint) { iint = integrity_iint_find(d_backing_inode(dentry)); if (!iint) @@ -491,15 +508,21 @@ static int evm_protect_xattr(struct mnt_idmap *idmap, if (strcmp(xattr_name, XATTR_NAME_EVM) == 0) { if (!capable(CAP_SYS_ADMIN)) return -EPERM; + if (is_unsupported_fs(dentry)) + return -EPERM; } else if (!evm_protected_xattr(xattr_name)) { if (!posix_xattr_acl(xattr_name)) return 0; + if (is_unsupported_fs(dentry)) + return 0; + evm_status = evm_verify_current_integrity(dentry); if ((evm_status == INTEGRITY_PASS) || (evm_status == INTEGRITY_NOXATTRS)) return 0; goto out; - } + } else if (is_unsupported_fs(dentry)) + return 0; evm_status = evm_verify_current_integrity(dentry); if (evm_status == INTEGRITY_NOXATTRS) { @@ -750,6 +773,9 @@ void evm_inode_post_setxattr(struct dentry *dentry, const char *xattr_name, if (!(evm_initialized & EVM_INIT_HMAC)) return; + if (is_unsupported_fs(dentry)) + return; + evm_update_evmxattr(dentry, xattr_name, xattr_value, xattr_value_len); } @@ -814,8 +840,12 @@ int evm_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, if (evm_initialized & EVM_ALLOW_METADATA_WRITES) return 0; + if (is_unsupported_fs(dentry)) + return 0; + if (!(ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID))) return 0; + evm_status = evm_verify_current_integrity(dentry); /* * Writing attrs is safe for portable signatures, as portable signatures @@ -859,6 +889,9 @@ void evm_inode_post_setattr(struct dentry *dentry, int ia_valid) if (!(evm_initialized & EVM_INIT_HMAC)) return; + if (is_unsupported_fs(dentry)) + return; + if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)) evm_update_evmxattr(dentry, NULL, NULL, 0); } |