diff options
| author | Christian Brauner <brauner@kernel.org> | 2025-09-12 13:52:52 +0200 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2025-09-19 14:26:16 +0200 |
| commit | e83f0b5d10dcf62833008327cb661c7d118bca85 (patch) | |
| tree | 8aea9ee6ffc99baf11533a770fc683efe76c8db9 /fs | |
| parent | 5222470b2fbb3740f931f189db33dd1367b1ae75 (diff) | |
nsfs: support exhaustive file handles
Pidfd file handles are exhaustive meaning they don't require a handle on
another pidfd to pass to open_by_handle_at() so it can derive the
filesystem to decode in. Instead it can be derived from the file
handle itself. The same is possible for namespace file handles.
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/fhandle.c | 6 | ||||
| -rw-r--r-- | fs/internal.h | 1 | ||||
| -rw-r--r-- | fs/nsfs.c | 10 |
3 files changed, 17 insertions, 0 deletions
diff --git a/fs/fhandle.c b/fs/fhandle.c index 68a7d2861c58..dd734d8828d0 100644 --- a/fs/fhandle.c +++ b/fs/fhandle.c @@ -11,6 +11,7 @@ #include <linux/personality.h> #include <linux/uaccess.h> #include <linux/compat.h> +#include <linux/nsfs.h> #include "internal.h" #include "mount.h" @@ -189,6 +190,11 @@ static int get_path_anchor(int fd, struct path *root) return 0; } + if (fd == FD_NSFS_ROOT) { + nsfs_get_root(root); + return 0; + } + return -EBADF; } diff --git a/fs/internal.h b/fs/internal.h index 38e8aab27bbd..a33d18ee5b74 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -355,3 +355,4 @@ int anon_inode_getattr(struct mnt_idmap *idmap, const struct path *path, int anon_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *attr); void pidfs_get_root(struct path *path); +void nsfs_get_root(struct path *path); diff --git a/fs/nsfs.c b/fs/nsfs.c index 926e2680414e..22765fcab18e 100644 --- a/fs/nsfs.c +++ b/fs/nsfs.c @@ -25,6 +25,14 @@ static struct vfsmount *nsfs_mnt; +static struct path nsfs_root_path = {}; + +void nsfs_get_root(struct path *path) +{ + *path = nsfs_root_path; + path_get(path); +} + static long ns_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg); static const struct file_operations ns_file_operations = { @@ -598,4 +606,6 @@ void __init nsfs_init(void) if (IS_ERR(nsfs_mnt)) panic("can't set nsfs up\n"); nsfs_mnt->mnt_sb->s_flags &= ~SB_NOUSER; + nsfs_root_path.mnt = nsfs_mnt; + nsfs_root_path.dentry = nsfs_mnt->mnt_root; } |