Skip to content

Commit

Permalink
fs: port i_{g,u}id_into_vfs{g,u}id() to mnt_idmap
Browse files Browse the repository at this point in the history 
Convert to struct mnt_idmap.
Remove legacy file_mnt_user_ns() and mnt_user_ns().

Last cycle we merged the necessary infrastructure in
256c8ae ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Christian Brauner (Microsoft) <[email protected]>
  • Loading branch information
@brauner
brauner committed Jan 19, 2023
1 parent 0dbe12f commit e67fe63
Show file tree
Hide file tree
Showing 33 changed files with 113 additions and 183 deletions.
24 changes: 8 additions & 16 deletions fs/attr.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -36,15 +36,13 @@
int setattr_should_drop_sgid(struct mnt_idmap *idmap,
const struct inode *inode)
{
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);
umode_t mode = inode->i_mode;

if (!(mode & S_ISGID))
return 0;
if (mode & S_IXGRP)
return ATTR_KILL_SGID;
if (!in_group_or_capable(idmap, inode,
i_gid_into_vfsgid(mnt_userns, inode)))
if (!in_group_or_capable(idmap, inode, i_gid_into_vfsgid(idmap, inode)))
return ATTR_KILL_SGID;
return 0;
}
Expand Down Expand Up @@ -98,9 +96,7 @@ EXPORT_SYMBOL(setattr_should_drop_suidgid);
static bool chown_ok(struct mnt_idmap *idmap,
const struct inode *inode, vfsuid_t ia_vfsuid)
{
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);

vfsuid_t vfsuid = i_uid_into_vfsuid(mnt_userns, inode);
vfsuid_t vfsuid = i_uid_into_vfsuid(idmap, inode);
if (vfsuid_eq_kuid(vfsuid, current_fsuid()) &&
vfsuid_eq(ia_vfsuid, vfsuid))
return true;
Expand All @@ -127,10 +123,8 @@ static bool chown_ok(struct mnt_idmap *idmap,
static bool chgrp_ok(struct mnt_idmap *idmap,
const struct inode *inode, vfsgid_t ia_vfsgid)
{
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);

vfsgid_t vfsgid = i_gid_into_vfsgid(mnt_userns, inode);
vfsuid_t vfsuid = i_uid_into_vfsuid(mnt_userns, inode);
vfsgid_t vfsgid = i_gid_into_vfsgid(idmap, inode);
vfsuid_t vfsuid = i_uid_into_vfsuid(idmap, inode);
if (vfsuid_eq_kuid(vfsuid, current_fsuid())) {
if (vfsgid_eq(ia_vfsgid, vfsgid))
return true;
Expand Down Expand Up @@ -169,7 +163,6 @@ static bool chgrp_ok(struct mnt_idmap *idmap,
int setattr_prepare(struct mnt_idmap *idmap, struct dentry *dentry,
struct iattr *attr)
{
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);
struct inode *inode = d_inode(dentry);
unsigned int ia_valid = attr->ia_valid;

Expand Down Expand Up @@ -207,7 +200,7 @@ int setattr_prepare(struct mnt_idmap *idmap, struct dentry *dentry,
if (ia_valid & ATTR_GID)
vfsgid = attr->ia_vfsgid;
else
vfsgid = i_gid_into_vfsgid(mnt_userns, inode);
vfsgid = i_gid_into_vfsgid(idmap, inode);

/* Also check the setgid bit! */
if (!in_group_or_capable(idmap, inode, vfsgid))
Expand Down Expand Up @@ -308,7 +301,6 @@ EXPORT_SYMBOL(inode_newsize_ok);
void setattr_copy(struct mnt_idmap *idmap, struct inode *inode,
const struct iattr *attr)
{
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);
unsigned int ia_valid = attr->ia_valid;

i_uid_update(idmap, attr, inode);
Expand All @@ -322,7 +314,7 @@ void setattr_copy(struct mnt_idmap *idmap, struct inode *inode,
if (ia_valid & ATTR_MODE) {
umode_t mode = attr->ia_mode;
if (!in_group_or_capable(idmap, inode,
i_gid_into_vfsgid(mnt_userns, inode)))
i_gid_into_vfsgid(idmap, inode)))
mode &= ~S_ISGID;
inode->i_mode = mode;
}
Expand Down Expand Up @@ -473,10 +465,10 @@ int notify_change(struct mnt_idmap *idmap, struct dentry *dentry,
* gids unless those uids & gids are being made valid.
*/
if (!(ia_valid & ATTR_UID) &&
!vfsuid_valid(i_uid_into_vfsuid(mnt_userns, inode)))
!vfsuid_valid(i_uid_into_vfsuid(idmap, inode)))
return -EOVERFLOW;
if (!(ia_valid & ATTR_GID) &&
!vfsgid_valid(i_gid_into_vfsgid(mnt_userns, inode)))
!vfsgid_valid(i_gid_into_vfsgid(idmap, inode)))
return -EOVERFLOW;

error = security_inode_setattr(idmap, dentry, attr);
Expand Down
4 changes: 1 addition & 3 deletions fs/coredump.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -645,7 +645,6 @@ void do_coredump(const kernel_siginfo_t *siginfo)
}
} else {
struct mnt_idmap *idmap;
struct user_namespace *mnt_userns;
struct inode *inode;
int open_flags = O_CREAT | O_RDWR | O_NOFOLLOW |
O_LARGEFILE | O_EXCL;
Expand Down Expand Up @@ -724,8 +723,7 @@ void do_coredump(const kernel_siginfo_t *siginfo)
* filesystem.
*/
idmap = file_mnt_idmap(cprm.file);
mnt_userns = mnt_idmap_owner(idmap);
if (!vfsuid_eq_kuid(i_uid_into_vfsuid(mnt_userns, inode),
if (!vfsuid_eq_kuid(i_uid_into_vfsuid(idmap, inode),
current_fsuid())) {
pr_info_ratelimited("Core dump to %s aborted: cannot preserve file owner\n",
cn.corename);
Expand Down
8 changes: 4 additions & 4 deletions fs/exec.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1596,7 +1596,7 @@ static void check_unsafe_exec(struct linux_binprm *bprm)
static void bprm_fill_uid(struct linux_binprm *bprm, struct file *file)
{
/* Handle suid and sgid on files */
struct user_namespace *mnt_userns;
struct mnt_idmap *idmap;
struct inode *inode = file_inode(file);
unsigned int mode;
vfsuid_t vfsuid;
Expand All @@ -1612,15 +1612,15 @@ static void bprm_fill_uid(struct linux_binprm *bprm, struct file *file)
if (!(mode & (S_ISUID|S_ISGID)))
return;

mnt_userns = file_mnt_user_ns(file);
idmap = file_mnt_idmap(file);

/* Be careful if suid/sgid is set */
inode_lock(inode);

/* reload atomically mode/uid/gid now that lock held */
mode = inode->i_mode;
vfsuid = i_uid_into_vfsuid(mnt_userns, inode);
vfsgid = i_gid_into_vfsgid(mnt_userns, inode);
vfsuid = i_uid_into_vfsuid(idmap, inode);
vfsgid = i_gid_into_vfsgid(idmap, inode);
inode_unlock(inode);

/* We ignore suid/sgid if there are no mappings for them in the ns */
Expand Down
3 changes: 1 addition & 2 deletions fs/f2fs/acl.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -209,7 +209,6 @@ static int f2fs_acl_update_mode(struct mnt_idmap *idmap,
struct posix_acl **acl)
{
umode_t mode = inode->i_mode;
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);
int error;

if (is_inode_flag_set(inode, FI_ACL_MODE))
Expand All @@ -220,7 +219,7 @@ static int f2fs_acl_update_mode(struct mnt_idmap *idmap,
return error;
if (error == 0)
*acl = NULL;
if (!vfsgid_in_group_p(i_gid_into_vfsgid(mnt_userns, inode)) &&
if (!vfsgid_in_group_p(i_gid_into_vfsgid(idmap, inode)) &&
!capable_wrt_inode_uidgid(idmap, inode, CAP_FSETID))
mode &= ~S_ISGID;
*mode_p = mode;
Expand Down
3 changes: 1 addition & 2 deletions fs/f2fs/file.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -907,7 +907,6 @@ static void __setattr_copy(struct mnt_idmap *idmap,
struct inode *inode, const struct iattr *attr)
{
unsigned int ia_valid = attr->ia_valid;
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);

i_uid_update(idmap, attr, inode);
i_gid_update(idmap, attr, inode);
Expand All @@ -919,7 +918,7 @@ static void __setattr_copy(struct mnt_idmap *idmap,
inode->i_ctime = attr->ia_ctime;
if (ia_valid & ATTR_MODE) {
umode_t mode = attr->ia_mode;
vfsgid_t vfsgid = i_gid_into_vfsgid(mnt_userns, inode);
vfsgid_t vfsgid = i_gid_into_vfsgid(idmap, inode);

if (!vfsgid_in_group_p(vfsgid) &&
!capable_wrt_inode_uidgid(idmap, inode, CAP_FSETID))
Expand Down
4 changes: 2 additions & 2 deletions fs/f2fs/recovery.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -258,9 +258,9 @@ static int recover_quota_data(struct inode *inode, struct page *page)
attr.ia_vfsuid = VFSUIDT_INIT(make_kuid(inode->i_sb->s_user_ns, i_uid));
attr.ia_vfsgid = VFSGIDT_INIT(make_kgid(inode->i_sb->s_user_ns, i_gid));

if (!vfsuid_eq(attr.ia_vfsuid, i_uid_into_vfsuid(&init_user_ns, inode)))
if (!vfsuid_eq(attr.ia_vfsuid, i_uid_into_vfsuid(&nop_mnt_idmap, inode)))
attr.ia_valid |= ATTR_UID;
if (!vfsgid_eq(attr.ia_vfsgid, i_gid_into_vfsgid(&init_user_ns, inode)))
if (!vfsgid_eq(attr.ia_vfsgid, i_gid_into_vfsgid(&nop_mnt_idmap, inode)))
attr.ia_valid |= ATTR_GID;

if (!attr.ia_valid)
Expand Down
8 changes: 4 additions & 4 deletions fs/fat/file.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -456,14 +456,14 @@ static int fat_sanitize_mode(const struct msdos_sb_info *sbi,
return 0;
}

static int fat_allow_set_time(struct user_namespace *mnt_userns,
static int fat_allow_set_time(struct mnt_idmap *idmap,
struct msdos_sb_info *sbi, struct inode *inode)
{
umode_t allow_utime = sbi->options.allow_utime;

if (!vfsuid_eq_kuid(i_uid_into_vfsuid(mnt_userns, inode),
if (!vfsuid_eq_kuid(i_uid_into_vfsuid(idmap, inode),
current_fsuid())) {
if (vfsgid_in_group_p(i_gid_into_vfsgid(mnt_userns, inode)))
if (vfsgid_in_group_p(i_gid_into_vfsgid(idmap, inode)))
allow_utime >>= 3;
if (allow_utime & MAY_WRITE)
return 1;
Expand All @@ -489,7 +489,7 @@ int fat_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
/* Check for setting the inode time. */
ia_valid = attr->ia_valid;
if (ia_valid & TIMES_SET_FLAGS) {
if (fat_allow_set_time(mnt_userns, sbi, inode))
if (fat_allow_set_time(idmap, sbi, inode))
attr->ia_valid &= ~TIMES_SET_FLAGS;
}

Expand Down
2 changes: 1 addition & 1 deletion fs/fuse/acl.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -99,7 +99,7 @@ int fuse_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
return ret;
}

if (!vfsgid_in_group_p(i_gid_into_vfsgid(&init_user_ns, inode)) &&
if (!vfsgid_in_group_p(i_gid_into_vfsgid(&nop_mnt_idmap, inode)) &&
!capable_wrt_inode_uidgid(&nop_mnt_idmap, inode, CAP_FSETID))
extra_flags |= FUSE_SETXATTR_ACL_KILL_SGID;

Expand Down
8 changes: 2 additions & 6 deletions fs/inode.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2327,9 +2327,8 @@ bool inode_owner_or_capable(struct mnt_idmap *idmap,
{
vfsuid_t vfsuid;
struct user_namespace *ns;
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);

vfsuid = i_uid_into_vfsuid(mnt_userns, inode);
vfsuid = i_uid_into_vfsuid(idmap, inode);
if (vfsuid_eq_kuid(vfsuid, current_fsuid()))
return true;

Expand Down Expand Up @@ -2498,14 +2497,11 @@ bool in_group_or_capable(struct mnt_idmap *idmap,
umode_t mode_strip_sgid(struct mnt_idmap *idmap,
const struct inode *dir, umode_t mode)
{
struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);

if ((mode & (S_ISGID | S_IXGRP)) != (S_ISGID | S_IXGRP))
return mode;
if (S_ISDIR(mode) || !dir || !(dir->i_mode & S_ISGID))
return mode;
if (in_group_or_capable(idmap, dir,
i_gid_into_vfsgid(mnt_userns, dir)))
if (in_group_or_capable(idmap, dir, i_gid_into_vfsgid(idmap, dir)))
return mode;
return mode & ~S_ISGID;
}
Expand Down
6 changes: 3 additions & 3 deletions fs/ksmbd/ndr.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -338,7 +338,7 @@ static int ndr_encode_posix_acl_entry(struct ndr *n, struct xattr_smb_acl *acl)
}

int ndr_encode_posix_acl(struct ndr *n,
struct user_namespace *user_ns,
struct mnt_idmap *idmap,
struct inode *inode,
struct xattr_smb_acl *acl,
struct xattr_smb_acl *def_acl)
Expand Down Expand Up @@ -374,11 +374,11 @@ int ndr_encode_posix_acl(struct ndr *n,
if (ret)
return ret;

vfsuid = i_uid_into_vfsuid(user_ns, inode);
vfsuid = i_uid_into_vfsuid(idmap, inode);
ret = ndr_write_int64(n, from_kuid(&init_user_ns, vfsuid_into_kuid(vfsuid)));
if (ret)
return ret;
vfsgid = i_gid_into_vfsgid(user_ns, inode);
vfsgid = i_gid_into_vfsgid(idmap, inode);
ret = ndr_write_int64(n, from_kgid(&init_user_ns, vfsgid_into_kgid(vfsgid)));
if (ret)
return ret;
Expand Down
2 changes: 1 addition & 1 deletion fs/ksmbd/ndr.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -14,7 +14,7 @@ struct ndr {

int ndr_encode_dos_attr(struct ndr *n, struct xattr_dos_attrib *da);
int ndr_decode_dos_attr(struct ndr *n, struct xattr_dos_attrib *da);
int ndr_encode_posix_acl(struct ndr *n, struct user_namespace *user_ns,
int ndr_encode_posix_acl(struct ndr *n, struct mnt_idmap *idmap,
struct inode *inode, struct xattr_smb_acl *acl,
struct xattr_smb_acl *def_acl);
int ndr_encode_v4_ntacl(struct ndr *n, struct xattr_ntacl *acl);
Expand Down
6 changes: 3 additions & 3 deletions fs/ksmbd/oplock.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1608,9 +1608,9 @@ void create_posix_rsp_buf(char *cc, struct ksmbd_file *fp)
{
struct create_posix_rsp *buf;
struct inode *inode = file_inode(fp->filp);
struct user_namespace *user_ns = file_mnt_user_ns(fp->filp);
vfsuid_t vfsuid = i_uid_into_vfsuid(user_ns, inode);
vfsgid_t vfsgid = i_gid_into_vfsgid(user_ns, inode);
struct mnt_idmap *idmap = file_mnt_idmap(fp->filp);
vfsuid_t vfsuid = i_uid_into_vfsuid(idmap, inode);
vfsgid_t vfsgid = i_gid_into_vfsgid(idmap, inode);

buf = (struct create_posix_rsp *)cc;
memset(buf, 0, sizeof(struct create_posix_rsp));
Expand Down
16 changes: 8 additions & 8 deletions fs/ksmbd/smb2pdu.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2476,11 +2476,11 @@ static int smb2_create_sd_buffer(struct ksmbd_work *work,
}

static void ksmbd_acls_fattr(struct smb_fattr *fattr,
struct user_namespace *mnt_userns,
struct mnt_idmap *idmap,
struct inode *inode)
{
vfsuid_t vfsuid = i_uid_into_vfsuid(mnt_userns, inode);
vfsgid_t vfsgid = i_gid_into_vfsgid(mnt_userns, inode);
vfsuid_t vfsuid = i_uid_into_vfsuid(idmap, inode);
vfsgid_t vfsgid = i_gid_into_vfsgid(idmap, inode);

fattr->cf_uid = vfsuid_into_kuid(vfsuid);
fattr->cf_gid = vfsgid_into_kgid(vfsgid);
Expand Down Expand Up @@ -2985,7 +2985,7 @@ int smb2_open(struct ksmbd_work *work)
struct smb_ntsd *pntsd;
int pntsd_size, ace_num = 0;

ksmbd_acls_fattr(&fattr, user_ns, inode);
ksmbd_acls_fattr(&fattr, idmap, inode);
if (fattr.cf_acls)
ace_num = fattr.cf_acls->a_count;
if (fattr.cf_dacls)
Expand Down Expand Up @@ -4725,9 +4725,9 @@ static int find_file_posix_info(struct smb2_query_info_rsp *rsp,
{
struct smb311_posix_qinfo *file_info;
struct inode *inode = file_inode(fp->filp);
struct user_namespace *user_ns = file_mnt_user_ns(fp->filp);
vfsuid_t vfsuid = i_uid_into_vfsuid(user_ns, inode);
vfsgid_t vfsgid = i_gid_into_vfsgid(user_ns, inode);
struct mnt_idmap *idmap = file_mnt_idmap(fp->filp);
vfsuid_t vfsuid = i_uid_into_vfsuid(idmap, inode);
vfsgid_t vfsgid = i_gid_into_vfsgid(idmap, inode);
u64 time;
int out_buf_len = sizeof(struct smb311_posix_qinfo) + 32;

Expand Down Expand Up @@ -5178,7 +5178,7 @@ static int smb2_get_info_sec(struct ksmbd_work *work,
idmap = file_mnt_idmap(fp->filp);
user_ns = mnt_idmap_owner(idmap);
inode = file_inode(fp->filp);
ksmbd_acls_fattr(&fattr, user_ns, inode);
ksmbd_acls_fattr(&fattr, idmap, inode);

if (test_share_config_flag(work->tcon->share_conf,
KSMBD_SHARE_FLAG_ACL_XATTR))
Expand Down
4 changes: 2 additions & 2 deletions fs/ksmbd/vfs.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1468,7 +1468,7 @@ int ksmbd_vfs_set_sd_xattr(struct ksmbd_conn *conn,
def_smb_acl = ksmbd_vfs_make_xattr_posix_acl(user_ns, inode,
ACL_TYPE_DEFAULT);

rc = ndr_encode_posix_acl(&acl_ndr, user_ns, inode,
rc = ndr_encode_posix_acl(&acl_ndr, idmap, inode,
smb_acl, def_smb_acl);
if (rc) {
pr_err("failed to encode ndr to posix acl\n");
Expand Down Expand Up @@ -1531,7 +1531,7 @@ int ksmbd_vfs_get_sd_xattr(struct ksmbd_conn *conn,
def_smb_acl = ksmbd_vfs_make_xattr_posix_acl(user_ns, inode,
ACL_TYPE_DEFAULT);

rc = ndr_encode_posix_acl(&acl_ndr, user_ns, inode, smb_acl,
rc = ndr_encode_posix_acl(&acl_ndr, idmap, inode, smb_acl,
def_smb_acl);
if (rc) {
pr_err("failed to encode ndr to posix acl\n");
Expand Down
Loading

0 comments on commit e67fe63

Please sign in to comment.