On Tue, 2024-04-16 at 10:05 +0200, Miklos Szeredi wrote: > On Mon, 15 Apr 2024 at 20:35, Mimi Zohar <zohar@xxxxxxxxxxxxx> wrote: > > > Although "Changes to the underlying filesystems while part of a mounted overlay > > filesystem are not allowed.", from an integrity perspective these changes might > > affect overlay files. So they need to be detected and possibly re-measured, re- > > appraised, and/or re-audited [1, 2]. > > How are changes of non-overlay files detected? Originally there was a single measureent unless the filesystem was mounted with SB_I_VERSION. With commit a2a2c3c8580a ("ima: Use i_version only when filesystem supports it") this changed to always re-measure the file if the filesystem wasn't mounted with SB_I_VERSION. With commit db1d1e8b9867 ("IMA: use vfs_getattr_nosec to get the i_version") it's not directly accessing i_version. thanks, Mimi