| Message ID | 20240712-vfs-mount-8fd93381a87f@brauner (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [GIT,PULL,for,v6.11] vfs mount | expand |
The pull request you sent on Fri, 12 Jul 2024 15:59:50 +0200:
> git@gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs tags/vfs-6.11.mount
has been merged into torvalds/linux.git:
https://git.kernel.org/torvalds/c/f608cabaeda472887c008e42398e8fca14e8f411
Thank you!
Hey Linus, /* Summary */ This contains work to extend the abilities of listmount() and statmount() and various fixes and cleanups. Features: - Allow iterating through mounts via listmount() from newest to oldest. This makes it possible for mount(8) to keep iterating the mount table in reverse order so it gets newest mounts first. - Relax permissions on listmount() and statmount(). It's not necessary to have capabilities in the initial namespace. It's sufficient to have capabilities in the owning namespace of the mount namespace we're located in to list unreachable mounts in that namespace. - Extend both listmount() and statmount() to list and stat mounts in foreign mount namespaces. Currently the only way to iterate over mount entries in mount namespaces that aren't in the caller's mount namespace is by crawling through /proc in order to find /proc/<pid>/mountinfo for the relevant mount namespace. This is both very clumsy and hugely inefficient. So extend struct mnt_id_req with a new member that allows to specify the mount namespace id of the mount namespace we want to look at. Luckily internally we already have most of the infrastructure for this so we just need to expose it to userspace. Give userspace a way to retrieve the id of a mount namespace via statmount() and through a new nsfs ioctl() on mount namespace file descriptor. This comes with appropriate selftests. - Expose mount options through statmount(). Currently if userspace wants to get mount options for a mount and with statmount(), they still have to open /proc/<pid>/mountinfo to parse mount options. Simply the information through statmount() directly. Afterwards it's possible to only rely on statmount() and listmount() to retrieve all and more information than /proc/<pid>/mountinfo provides. This comes with appropriate selftests. Fixes: - Avoid copying to userspace under the namespace semaphore in listmount. Cleanups: - Simplify the error handling in listmount by relying on our newly added cleanup infrastructure. - Refuse invalid mount ids early for both listmount and statmount. /* Testing */ clang: Debian clang version 16.0.6 (26) gcc: (Debian 13.2.0-24) All patches are based on v6.10-rc1 and have been sitting in linux-next. No build failures or warnings were observed. /* Conflicts */ No known conflicts. The following changes since commit 1613e604df0cd359cf2a7fbd9be7a0bcfacfabd0: Linux 6.10-rc1 (2024-05-26 15:20:12 -0700) are available in the Git repository at: git@gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs tags/vfs-6.11.mount for you to fetch changes up to 4bed843b10004d9101b49ac7270131051c39a92b: fs: reject invalid last mount id early (2024-07-08 06:32:18 +0200) Please consider pulling these changes from the signed vfs-6.11.mount tag. Thanks! Christian ---------------------------------------------------------------- vfs-6.11.mount ---------------------------------------------------------------- Christian Brauner (15): path: add cleanup helper fs: don't copy to userspace under namespace semaphore fs: simplify error handling fs: relax permissions for listmount() listmount: allow listing in reverse order fs: relax permissions for statmount() fs: Allow listmount() in foreign mount namespace fs: Allow statmount() in foreign mount namespace Merge patch series "Support foreign mount namespace with statmount/listmount" fs: use guard for namespace_sem in statmount() Merge patch series "Add the ability to query mount options in statmount" fs: only copy to userspace on success in listmount() fs: find rootfs mount of the mount namespace fs: refuse mnt id requests with invalid ids early fs: reject invalid last mount id early Josef Bacik (7): fs: keep an index of current mount namespaces fs: export the mount ns id via statmount fs: add an ioctl to get the mnt ns id from nsfs selftests: add a test for the foreign mnt ns extensions fs: rename show_mnt_opts -> show_vfsmnt_opts fs: export mount options via statmount() sefltests: extend the statmount test for mount options fs/mount.h | 2 + fs/namespace.c | 450 +++++++++++++++++---- fs/nsfs.c | 14 + fs/proc_namespace.c | 6 +- include/linux/path.h | 9 + include/uapi/linux/mount.h | 10 +- include/uapi/linux/nsfs.h | 2 + .../selftests/filesystems/statmount/Makefile | 2 +- .../selftests/filesystems/statmount/statmount.h | 46 +++ .../filesystems/statmount/statmount_test.c | 144 +++++-- .../filesystems/statmount/statmount_test_ns.c | 364 +++++++++++++++++ 11 files changed, 926 insertions(+), 123 deletions(-) create mode 100644 tools/testing/selftests/filesystems/statmount/statmount.h create mode 100644 tools/testing/selftests/filesystems/statmount/statmount_test_ns.c