On Fri, Jan 17, 2025 at 07:39:09AM +1030, Qu Wenruo wrote: > The original problem is that we can get very weird device path, like > '/proc/<pid>/<fd>' or any blockdev node created by the end user, as > mount source, which can cause various problems in mount_info for end users. You do realize that different namespaces may very well have the same pathname resolve to different things, right? So "userland can't open a device pathname it sees in /proc/self/mountinfo" was not going to be solved that way anyway... While we are at it, it is entirely possible to have a trimmed-down ramfs with the minimal set of static device nodes mounted on /dev in user's namespace, with not a block device in sight - despite having a bunch of local filesystems mounted.
