kernel/linux.git/include/linux/proc_ns.h, branch v6.19.11

ns: move ns type into struct ns_common

2025-09-25T07:23:54+00:00

It's misplaced in struct proc_ns_operations and ns->ops might be NULL if the namespace is compiled out but we still want to know the type of the namespace for the initial namespace struct. Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

ns: add ns_common_free()

2025-09-19T14:22:36+00:00

And drop ns_free_inum(). Anything common that can be wasted centrally should be wasted in the new common helper. Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

nscommon: move to separate file

2025-09-19T12:26:18+00:00

It's really awkward spilling the ns common infrastructure into multiple headers. Move it to a separate file. Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

nstree: make iterator generic

2025-09-19T12:26:14+00:00

Move the namespace iteration infrastructure originally introduced for mount namespaces into a generic library usable by all namespace types. Signed-off-by: Christian Brauner

ns: remove ns_alloc_inum()

2025-09-19T12:26:14+00:00

It's now unused. Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

ns: uniformly initialize ns_common

2025-09-19T12:26:13+00:00

No point in cargo-culting the same code across all the different types. Use one common initializer. Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

nsfs: add nsfs.h header

2025-09-19T12:26:12+00:00

And move the stuff out from proc_ns.h where it really doesn't belong. Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

uapi: export PROCFS_ROOT_INO

2025-07-10T07:39:18+00:00

The root inode of /proc having a fixed inode number has been part of the core kernel ABI since its inception, and recently some userspace programs (mainly container runtimes) have started to explicitly depend on this behaviour. The main reason this is useful to userspace is that by checking that a suspect /proc handle has fstype PROC_SUPER_MAGIC and is PROCFS_ROOT_INO, they can then use openat2(RESOLVE_{NO_{XDEV,MAGICLINK},BENEATH}) to ensure that there isn't a bind-mount that replaces some procfs file with a different one. This kind of attack has lead to security issues in container runtimes in the past (such as CVE-2019-19921) and libraries like libpathrs[1] use this feature of procfs to provide safe procfs handling functions. There was also some trailing whitespace in the "struct proc_dir_entry" initialiser, so fix that up as well. [1]: https://github.com/openSUSE/libpathrs Signed-off-by: Aleksa Sarai Link: https://lore.kernel.org/20250708-uapi-procfs-root-ino-v1-1-6ae61e97c79b@cyphar.com Signed-off-by: Christian Brauner

mntns: use stable inode number for initial mount ns

2025-06-11T09:59:08+00:00

Apart from the network and mount namespace all other namespaces expose a stable inode number and userspace has been relying on that for a very long time now. It's very much heavily used API. Align the mount namespace and use a stable inode number from the reserved procfs inode number space so this is consistent across all namespaces. Link: https://lore.kernel.org/20250606-work-nsfs-v1-3-b8749c9a8844@kernel.org Signed-off-by: Christian Brauner

netns: use stable inode number for initial mount ns

2025-06-11T09:59:08+00:00

Apart from the network and mount namespace all other namespaces expose a stable inode number and userspace has been relying on that for a very long time now. It's very much heavily used API. Align the network namespace and use a stable inode number from the reserved procfs inode number space so this is consistent across all namespaces. Link: https://lore.kernel.org/20250606-work-nsfs-v1-2-b8749c9a8844@kernel.org Reviewed-by: Jakub Kicinski Signed-off-by: Christian Brauner