Re: [PATCH v7 6/6] evm: Support multiple LSMs providing an xattr
Mimi Zohar <[email protected]>
| Newsgroups | gmane.linux.kernel,gmane.comp.file-systems.ocfs2.devel,gmane.comp.file-systems.reiserfs.general,gmane.linux.kernel.lsm |
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| Message-ID | <[email protected]> |
On Thu, 2022-12-01 at 11:41 +0100, Roberto Sassu wrote: > From: Roberto Sassu <[email protected]> > > Currently, evm_inode_init_security() processes a single LSM xattr from > the array passed by security_inode_init_security(), and calculates the > HMAC on it and other inode metadata. > > Given that initxattrs() callbacks, called by > security_inode_init_security(), expect that this array is terminated when > the xattr name is set to NULL, reuse the same assumption to scan all xattrs > and to calculate the HMAC on all of them. > > Signed-off-by: Roberto Sassu <[email protected]> > Reviewed-by: Casey Schaufler <[email protected]> Normally changing the contents of the EVM HMAC calculation would break existing systems. Assuming for the time being this is safe, at what point will it affect backwards compatability? Should it be documented now or then? -- thanks, Mimi