summaryrefslogtreecommitdiff
path: root/fs
diff options
context:
space:
mode:
Diffstat (limited to 'fs')
-rw-r--r--fs/cachefiles/bind.c2
-rw-r--r--fs/ecryptfs/main.c2
-rw-r--r--fs/ksmbd/smbacl.c19
-rw-r--r--fs/ksmbd/smbacl.h5
-rw-r--r--fs/namespace.c53
-rw-r--r--fs/nfsd/export.c2
-rw-r--r--fs/open.c8
-rw-r--r--fs/overlayfs/super.c2
-rw-r--r--fs/posix_acl.c17
-rw-r--r--fs/proc_namespace.c2
-rw-r--r--fs/xfs/xfs_inode.c8
-rw-r--r--fs/xfs/xfs_linux.h1
-rw-r--r--fs/xfs/xfs_symlink.c4
13 files changed, 73 insertions, 52 deletions
diff --git a/fs/cachefiles/bind.c b/fs/cachefiles/bind.c
index d463d89f5db8..146291be6263 100644
--- a/fs/cachefiles/bind.c
+++ b/fs/cachefiles/bind.c
@@ -117,7 +117,7 @@ static int cachefiles_daemon_add_cache(struct cachefiles_cache *cache)
root = path.dentry;
ret = -EINVAL;
- if (mnt_user_ns(path.mnt) != &init_user_ns) {
+ if (is_idmapped_mnt(path.mnt)) {
pr_warn("File cache on idmapped mounts not supported");
goto error_unsupported;
}
diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
index d66bbd2df191..2dd23a82e0de 100644
--- a/fs/ecryptfs/main.c
+++ b/fs/ecryptfs/main.c
@@ -537,7 +537,7 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
goto out_free;
}
- if (mnt_user_ns(path.mnt) != &init_user_ns) {
+ if (is_idmapped_mnt(path.mnt)) {
rc = -EINVAL;
printk(KERN_ERR "Mounting on idmapped mounts currently disallowed\n");
goto out_free;
diff --git a/fs/ksmbd/smbacl.c b/fs/ksmbd/smbacl.c
index bd792db32623..6ecf55ea1fed 100644
--- a/fs/ksmbd/smbacl.c
+++ b/fs/ksmbd/smbacl.c
@@ -9,6 +9,7 @@
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/string.h>
+#include <linux/mnt_idmapping.h>
#include "smbacl.h"
#include "smb_common.h"
@@ -274,14 +275,7 @@ static int sid_to_id(struct user_namespace *user_ns,
uid_t id;
id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
- /*
- * Translate raw sid into kuid in the server's user
- * namespace.
- */
- uid = make_kuid(&init_user_ns, id);
-
- /* If this is an idmapped mount, apply the idmapping. */
- uid = kuid_from_mnt(user_ns, uid);
+ uid = mapped_kuid_user(user_ns, &init_user_ns, KUIDT_INIT(id));
if (uid_valid(uid)) {
fattr->cf_uid = uid;
rc = 0;
@@ -291,14 +285,7 @@ static int sid_to_id(struct user_namespace *user_ns,
gid_t id;
id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
- /*
- * Translate raw sid into kgid in the server's user
- * namespace.
- */
- gid = make_kgid(&init_user_ns, id);
-
- /* If this is an idmapped mount, apply the idmapping. */
- gid = kgid_from_mnt(user_ns, gid);
+ gid = mapped_kgid_user(user_ns, &init_user_ns, KGIDT_INIT(id));
if (gid_valid(gid)) {
fattr->cf_gid = gid;
rc = 0;
diff --git a/fs/ksmbd/smbacl.h b/fs/ksmbd/smbacl.h
index 73e08cad412b..811af3309429 100644
--- a/fs/ksmbd/smbacl.h
+++ b/fs/ksmbd/smbacl.h
@@ -11,6 +11,7 @@
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/posix_acl.h>
+#include <linux/mnt_idmapping.h>
#include "mgmt/tree_connect.h"
@@ -216,7 +217,7 @@ static inline uid_t posix_acl_uid_translate(struct user_namespace *mnt_userns,
kuid_t kuid;
/* If this is an idmapped mount, apply the idmapping. */
- kuid = kuid_into_mnt(mnt_userns, pace->e_uid);
+ kuid = mapped_kuid_fs(mnt_userns, &init_user_ns, pace->e_uid);
/* Translate the kuid into a userspace id ksmbd would see. */
return from_kuid(&init_user_ns, kuid);
@@ -228,7 +229,7 @@ static inline gid_t posix_acl_gid_translate(struct user_namespace *mnt_userns,
kgid_t kgid;
/* If this is an idmapped mount, apply the idmapping. */
- kgid = kgid_into_mnt(mnt_userns, pace->e_gid);
+ kgid = mapped_kgid_fs(mnt_userns, &init_user_ns, pace->e_gid);
/* Translate the kgid into a userspace id ksmbd would see. */
return from_kgid(&init_user_ns, kgid);
diff --git a/fs/namespace.c b/fs/namespace.c
index b696543adab8..dc31ad6b370f 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -31,6 +31,7 @@
#include <uapi/linux/mount.h>
#include <linux/fs_context.h>
#include <linux/shmem_fs.h>
+#include <linux/mnt_idmapping.h>
#include "pnode.h"
#include "internal.h"
@@ -561,7 +562,7 @@ static void free_vfsmnt(struct mount *mnt)
struct user_namespace *mnt_userns;
mnt_userns = mnt_user_ns(&mnt->mnt);
- if (mnt_userns != &init_user_ns)
+ if (!initial_idmapping(mnt_userns))
put_user_ns(mnt_userns);
kfree_const(mnt->mnt_devname);
#ifdef CONFIG_SMP
@@ -965,6 +966,7 @@ static struct mount *skip_mnt_tree(struct mount *p)
struct vfsmount *vfs_create_mount(struct fs_context *fc)
{
struct mount *mnt;
+ struct user_namespace *fs_userns;
if (!fc->root)
return ERR_PTR(-EINVAL);
@@ -982,6 +984,10 @@ struct vfsmount *vfs_create_mount(struct fs_context *fc)
mnt->mnt_mountpoint = mnt->mnt.mnt_root;
mnt->mnt_parent = mnt;
+ fs_userns = mnt->mnt.mnt_sb->s_user_ns;
+ if (!initial_idmapping(fs_userns))
+ mnt->mnt.mnt_userns = get_user_ns(fs_userns);
+
lock_mount_hash();
list_add_tail(&mnt->mnt_instance, &mnt->mnt.mnt_sb->s_mounts);
unlock_mount_hash();
@@ -1072,7 +1078,7 @@ static struct mount *clone_mnt(struct mount *old, struct dentry *root,
atomic_inc(&sb->s_active);
mnt->mnt.mnt_userns = mnt_user_ns(&old->mnt);
- if (mnt->mnt.mnt_userns != &init_user_ns)
+ if (!initial_idmapping(mnt->mnt.mnt_userns))
mnt->mnt.mnt_userns = get_user_ns(mnt->mnt.mnt_userns);
mnt->mnt.mnt_sb = sb;
mnt->mnt.mnt_root = dget(root);
@@ -3927,28 +3933,32 @@ static unsigned int recalc_flags(struct mount_kattr *kattr, struct mount *mnt)
static int can_idmap_mount(const struct mount_kattr *kattr, struct mount *mnt)
{
struct vfsmount *m = &mnt->mnt;
+ struct user_namespace *fs_userns = m->mnt_sb->s_user_ns;
if (!kattr->mnt_userns)
return 0;
/*
+ * Creating an idmapped mount with the filesystem wide idmapping
+ * doesn't make sense so block that. We don't allow mushy semantics.
+ */
+ if (kattr->mnt_userns == fs_userns)
+ return -EINVAL;
+
+ /*
* Once a mount has been idmapped we don't allow it to change its
* mapping. It makes things simpler and callers can just create
* another bind-mount they can idmap if they want to.
*/
- if (mnt_user_ns(m) != &init_user_ns)
+ if (is_idmapped_mnt(m))
return -EPERM;
/* The underlying filesystem doesn't support idmapped mounts yet. */
if (!(m->mnt_sb->s_type->fs_flags & FS_ALLOW_IDMAP))
return -EINVAL;
- /* Don't yet support filesystem mountable in user namespaces. */
- if (m->mnt_sb->s_user_ns != &init_user_ns)
- return -EINVAL;
-
/* We're not controlling the superblock. */
- if (!capable(CAP_SYS_ADMIN))
+ if (!ns_capable(fs_userns, CAP_SYS_ADMIN))
return -EPERM;
/* Mount has already been visible in the filesystem hierarchy. */
@@ -4002,14 +4012,27 @@ out:
static void do_idmap_mount(const struct mount_kattr *kattr, struct mount *mnt)
{
- struct user_namespace *mnt_userns;
+ struct user_namespace *mnt_userns, *old_mnt_userns;
if (!kattr->mnt_userns)
return;
+ /*
+ * We're the only ones able to change the mount's idmapping. So
+ * mnt->mnt.mnt_userns is stable and we can retrieve it directly.
+ */
+ old_mnt_userns = mnt->mnt.mnt_userns;
+
mnt_userns = get_user_ns(kattr->mnt_userns);
/* Pairs with smp_load_acquire() in mnt_user_ns(). */
smp_store_release(&mnt->mnt.mnt_userns, mnt_userns);
+
+ /*
+ * If this is an idmapped filesystem drop the reference we've taken
+ * in vfs_create_mount() before.
+ */
+ if (!initial_idmapping(old_mnt_userns))
+ put_user_ns(old_mnt_userns);
}
static void mount_setattr_commit(struct mount_kattr *kattr,
@@ -4133,13 +4156,15 @@ static int build_mount_idmapped(const struct mount_attr *attr, size_t usize,
}
/*
- * The init_user_ns is used to indicate that a vfsmount is not idmapped.
- * This is simpler than just having to treat NULL as unmapped. Users
- * wanting to idmap a mount to init_user_ns can just use a namespace
- * with an identity mapping.
+ * The initial idmapping cannot be used to create an idmapped
+ * mount. We use the initial idmapping as an indicator of a mount
+ * that is not idmapped. It can simply be passed into helpers that
+ * are aware of idmapped mounts as a convenient shortcut. A user
+ * can just create a dedicated identity mapping to achieve the same
+ * result.
*/
mnt_userns = container_of(ns, struct user_namespace, ns);
- if (mnt_userns == &init_user_ns) {
+ if (initial_idmapping(mnt_userns)) {
err = -EPERM;
goto out_fput;
}
diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 9421dae22737..668c7527b17e 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -427,7 +427,7 @@ static int check_export(struct path *path, int *flags, unsigned char *uuid)
return -EINVAL;
}
- if (mnt_user_ns(path->mnt) != &init_user_ns) {
+ if (is_idmapped_mnt(path->mnt)) {
dprintk("exp_export: export of idmapped mounts not yet supported.\n");
return -EINVAL;
}
diff --git a/fs/open.c b/fs/open.c
index f732fb94600c..9ff2f621b760 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -32,6 +32,7 @@
#include <linux/ima.h>
#include <linux/dnotify.h>
#include <linux/compat.h>
+#include <linux/mnt_idmapping.h>
#include "internal.h"
@@ -640,7 +641,7 @@ SYSCALL_DEFINE2(chmod, const char __user *, filename, umode_t, mode)
int chown_common(const struct path *path, uid_t user, gid_t group)
{
- struct user_namespace *mnt_userns;
+ struct user_namespace *mnt_userns, *fs_userns;
struct inode *inode = path->dentry->d_inode;
struct inode *delegated_inode = NULL;
int error;
@@ -652,8 +653,9 @@ int chown_common(const struct path *path, uid_t user, gid_t group)
gid = make_kgid(current_user_ns(), group);
mnt_userns = mnt_user_ns(path->mnt);
- uid = kuid_from_mnt(mnt_userns, uid);
- gid = kgid_from_mnt(mnt_userns, gid);
+ fs_userns = i_user_ns(inode);
+ uid = mapped_kuid_user(mnt_userns, fs_userns, uid);
+ gid = mapped_kgid_user(mnt_userns, fs_userns, gid);
retry_deleg:
newattrs.ia_valid = ATTR_CTIME;
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 265181c110ae..7bb0a47cb615 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -873,7 +873,7 @@ static int ovl_mount_dir_noesc(const char *name, struct path *path)
pr_err("filesystem on '%s' not supported\n", name);
goto out_put;
}
- if (mnt_user_ns(path->mnt) != &init_user_ns) {
+ if (is_idmapped_mnt(path->mnt)) {
pr_err("idmapped layers are currently not supported\n");
goto out_put;
}
diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 9323a854a60a..80acb6885cf9 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -23,6 +23,7 @@
#include <linux/export.h>
#include <linux/user_namespace.h>
#include <linux/namei.h>
+#include <linux/mnt_idmapping.h>
static struct posix_acl **acl_by_type(struct inode *inode, int type)
{
@@ -374,7 +375,9 @@ posix_acl_permission(struct user_namespace *mnt_userns, struct inode *inode,
goto check_perm;
break;
case ACL_USER:
- uid = kuid_into_mnt(mnt_userns, pa->e_uid);
+ uid = mapped_kuid_fs(mnt_userns,
+ i_user_ns(inode),
+ pa->e_uid);
if (uid_eq(uid, current_fsuid()))
goto mask;
break;
@@ -387,7 +390,9 @@ posix_acl_permission(struct user_namespace *mnt_userns, struct inode *inode,
}
break;
case ACL_GROUP:
- gid = kgid_into_mnt(mnt_userns, pa->e_gid);
+ gid = mapped_kgid_fs(mnt_userns,
+ i_user_ns(inode),
+ pa->e_gid);
if (in_group_p(gid)) {
found = 1;
if ((pa->e_perm & want) == want)
@@ -734,17 +739,17 @@ static void posix_acl_fix_xattr_userns(
case ACL_USER:
uid = make_kuid(from, le32_to_cpu(entry->e_id));
if (from_user)
- uid = kuid_from_mnt(mnt_userns, uid);
+ uid = mapped_kuid_user(mnt_userns, &init_user_ns, uid);
else
- uid = kuid_into_mnt(mnt_userns, uid);
+ uid = mapped_kuid_fs(mnt_userns, &init_user_ns, uid);
entry->e_id = cpu_to_le32(from_kuid(to, uid));
break;
case ACL_GROUP:
gid = make_kgid(from, le32_to_cpu(entry->e_id));
if (from_user)
- gid = kgid_from_mnt(mnt_userns, gid);
+ gid = mapped_kgid_user(mnt_userns, &init_user_ns, gid);
else
- gid = kgid_into_mnt(mnt_userns, gid);
+ gid = mapped_kgid_fs(mnt_userns, &init_user_ns, gid);
entry->e_id = cpu_to_le32(from_kgid(to, gid));
break;
default:
diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c
index 392ef5162655..49650e54d2f8 100644
--- a/fs/proc_namespace.c
+++ b/fs/proc_namespace.c
@@ -80,7 +80,7 @@ static void show_mnt_opts(struct seq_file *m, struct vfsmount *mnt)
seq_puts(m, fs_infop->str);
}
- if (mnt_user_ns(mnt) != &init_user_ns)
+ if (is_idmapped_mnt(mnt))
seq_puts(m, ",idmapped");
}
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 6771f357ad2c..04bf467b1090 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -988,8 +988,8 @@ xfs_create(
/*
* Make sure that we have allocated dquot(s) on disk.
*/
- error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
- mapped_fsgid(mnt_userns), prid,
+ error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns, &init_user_ns),
+ mapped_fsgid(mnt_userns, &init_user_ns), prid,
XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
&udqp, &gdqp, &pdqp);
if (error)
@@ -1142,8 +1142,8 @@ xfs_create_tmpfile(
/*
* Make sure that we have allocated dquot(s) on disk.
*/
- error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
- mapped_fsgid(mnt_userns), prid,
+ error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns, &init_user_ns),
+ mapped_fsgid(mnt_userns, &init_user_ns), prid,
XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
&udqp, &gdqp, &pdqp);
if (error)
diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
index c174262a074e..09a8fba84ff9 100644
--- a/fs/xfs/xfs_linux.h
+++ b/fs/xfs/xfs_linux.h
@@ -61,6 +61,7 @@ typedef __u32 xfs_nlink_t;
#include <linux/ratelimit.h>
#include <linux/rhashtable.h>
#include <linux/xattr.h>
+#include <linux/mnt_idmapping.h>
#include <asm/page.h>
#include <asm/div64.h>
diff --git a/fs/xfs/xfs_symlink.c b/fs/xfs/xfs_symlink.c
index fc2c6a404647..a31d2e5d0321 100644
--- a/fs/xfs/xfs_symlink.c
+++ b/fs/xfs/xfs_symlink.c
@@ -184,8 +184,8 @@ xfs_symlink(
/*
* Make sure that we have allocated dquot(s) on disk.
*/
- error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
- mapped_fsgid(mnt_userns), prid,
+ error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns, &init_user_ns),
+ mapped_fsgid(mnt_userns, &init_user_ns), prid,
XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
&udqp, &gdqp, &pdqp);
if (error)
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-04 05:18:54 +0000