From 20267e45276da9d4f4cb7f4bb274ccdc94b9cc22 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Tue, 21 Apr 2015 13:59:31 -0400 Subject: evm: labeling pseudo filesystems exception commit 5101a1850bb7ccbf107929dee9af0cd2f400940f upstream. 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 [ luis: backported to 3.16: - added magic.h header file ] Signed-off-by: Luis Henriques --- security/integrity/evm/evm_main.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'security') diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index 970772c731ff..41f32259437c 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include "evm.h" @@ -290,6 +291,17 @@ 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) -- cgit v1.2.3