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Peter Anvin" , "Kees Cook" , "Farid Zakaria" , "Al Viro" , "Jan Kara" , LKML , "Jonathan Corbet" , linux-doc Message-Id: <09b4735f-c04e-40f3-a7f5-254b7918fbfd@app.fastmail.com> In-Reply-To: References: <20260723-work-failfs-v1-0-3f69b9a9e958@kernel.org> <20260723-work-failfs-v1-4-3f69b9a9e958@kernel.org> <20260723-mahlt-abhob-semantik-21254c8d36cb@brauner> <20260723-wutausbruch-aufraffen-gipfel-73767d4aa71f@brauner> Subject: Re: [PATCH RFC 4/7] fs: support FD_FAILFS_ROOT in fchroot() Content-Type: text/plain Content-Transfer-Encoding: 7bit Very happy to see this patch series appear; thanks Christian! Also happy with where this specific thread is going. I will just add that an additional flag in fs_struct to force RESOLVE_BENEATH in *all* path lookup would also be nice. The combination of: root = pwd = failfs; chroot_locked = false; always_resolve_beneath = true; goes along way to getting Capsicum's "capability mode". Then we just need to figure out things like more capabilities for directory file descriptors per Andy's brainstorming thread thread (which I ought to get to replying to). John