diff options
| author | Mimi Zohar <zohar@linux.vnet.ibm.com> | 2015-04-21 13:59:31 -0400 |
|---|---|---|
| committer | Sasha Levin <sasha.levin@oracle.com> | 2015-08-04 14:29:15 -0400 |
| commit | 7a889192e322242945874e52b25f88c8841c8f47 (patch) | |
| tree | c13ce032bef515fa298ade9acd1330ca8ebb1b79 /security | |
| parent | 66db51c9f7b2fe7ebdfa753b2aa9abbb9feddc87 (diff) | |
| download | lwn-7a889192e322242945874e52b25f88c8841c8f47.tar.gz lwn-7a889192e322242945874e52b25f88c8841c8f47.zip | |
evm: labeling pseudo filesystems exception
[ Upstream commit 5101a1850bb7ccbf107929dee9af0cd2f400940f ]
To prevent offline stripping of existing file xattrs and relabeling of
them at runtime, EVM allows only newly created files to be labeled. As
pseudo filesystems are not persistent, stripping of xattrs is not a
concern.
Some LSMs defer file labeling on pseudo filesystems. This patch
permits the labeling of existing files on pseudo files systems.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'security')
| -rw-r--r-- | security/integrity/evm/evm_main.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index c5ee1a7c5e8a..4ada1a97a60b 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -22,6 +22,7 @@ #include <linux/xattr.h> #include <linux/integrity.h> #include <linux/evm.h> +#include <linux/magic.h> #include <crypto/hash.h> #include "evm.h" @@ -291,6 +292,17 @@ static int evm_protect_xattr(struct dentry *dentry, const char *xattr_name, iint = integrity_iint_find(dentry->d_inode); if (iint && (iint->flags & IMA_NEW_FILE)) return 0; + + /* exception for pseudo filesystems */ + if (dentry->d_inode->i_sb->s_magic == TMPFS_MAGIC + || dentry->d_inode->i_sb->s_magic == SYSFS_MAGIC) + return 0; + + integrity_audit_msg(AUDIT_INTEGRITY_METADATA, + dentry->d_inode, dentry->d_name.name, + "update_metadata", + integrity_status_msg[evm_status], + -EPERM, 0); } out: if (evm_status != INTEGRITY_PASS) |