On Mon, Feb 03, 2014 at 01:31:19PM -0800, Linus Torvalds wrote: > If the protocol is path-based (and it happens, and it's actually the > *correct* thing to do for a network filesystem, rather than the > idiotic "file handle" crap that tries to emulate the unix inode > semantics in the protocol), then the inode is simply not sufficient. > > And no, d_find_alias() is not correct or sufficient either. It can > work in practice (and probably does perfectly fine 99.9% of the time), > but it can equally well give the *wrong* dentry: yes, the dentry it > returns would have been a valid dentry for somebody at some time, but > it might be a stale dentry *now*, and it might be the wrong dentry for > the current user (because the current user may not have permissions to > that particular path, even if the user has permissions through his > *own* path). > > So I really think you're *fundamentally* incorrect when you say > "result *is* a function of inode alone". Which fs are you talking about? For 9P it *is* a function of inode alone. For CIFS there's no wrong dentry to pick - it doesn't have links to start with. If we really have hardlinks, the result of permission check would better be a function of inode itself - as in, "if it gives different results for two pathnames reachable for the same user, we have a bug". -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
