gOn Mon, 2023-09-04 at 15:34 +0200, Roberto Sassu wrote: > From: Roberto Sassu <roberto.sassu@xxxxxxxxxx> > > In preparation for moving IMA and EVM to the LSM infrastructure, introduce > the inode_post_setattr hook. > > It is useful for EVM to recalculate the HMAC on modified file attributes > and other file metadata, after it verified the HMAC of current file > metadata with the inode_setattr hook. "useful"? At inode_setattr hook, EVM verifies the file's existing HMAC value. At inode_post_setattr, EVM re-calculates the file's HMAC based on the modified file attributes and other file metadata. > > LSMs should use the new hook instead of inode_setattr, when they need to > know that the operation was done successfully (not known in inode_setattr). > The new hook cannot return an error and cannot cause the operation to be > reverted. Other LSMs could similarly update security xattrs or ... > > Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx> Reviewed-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
