leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

evm: reset EVM status when file attributes change

Browse Source 
The EVM verification status is cached in iint->evm_status and if it
was successful, never re-verified again when IMA passes the 'iint' to
evm_verifyxattr().

When file attributes or extended attributes change, we may wish to
re-verify EVM integrity as well.  For example, after setting a digital
signature we may need to re-verify the signature and update the
iint->flags that there is an EVM signature.

This patch enables that by resetting evm_status to INTEGRITY_UKNOWN
state.

Changes in v2:
* Flag setting moved to EVM layer

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This commit is contained in:
Dmitry Kasatkin 2015-10-22 21:26:42 +03:00 committed by Mimi Zohar
parent 7626676320
commit 523b74b16b
1 changed files with 13 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
security/integrity/evm/evm_main.c
View File

@ -358,6 +358,15 @@ int evm_inode_removexattr(struct dentry *dentry, const char *xattr_name)
return evm_protect_xattr(dentry, xattr_name, NULL, 0);
}
static void evm_reset_status(struct inode *inode)
{
struct integrity_iint_cache *iint;
iint = integrity_iint_find(inode);
if (iint)
iint->evm_status = INTEGRITY_UNKNOWN;
}
/**
* evm_inode_post_setxattr - update 'security.evm' to reflect the changes
* @dentry: pointer to the affected dentry
@ -378,6 +387,8 @@ void evm_inode_post_setxattr(struct dentry *dentry, const char *xattr_name,
&& !posix_xattr_acl(xattr_name)))
return;
evm_reset_status(dentry->d_inode);
evm_update_evmxattr(dentry, xattr_name, xattr_value, xattr_value_len);
}
@ -396,6 +407,8 @@ void evm_inode_post_removexattr(struct dentry *dentry, const char *xattr_name)
if (!evm_initialized || !evm_protected_xattr(xattr_name))
return;
evm_reset_status(dentry->d_inode);
evm_update_evmxattr(dentry, xattr_name, NULL, 0);
}