On Tue, Feb 18, 2020 at 01:00:20PM -0800, Christoph Hellwig wrote:
> Remove the XFS wrappers for converting from and to the kuid/kgid types.
> Mostly this means switching to VFS i_{u,g}id_{read,write} helpers, but
> in a few spots the calls to the conversion functions is open coded.
> To match the use of sb->s_user_ns in the helpers and other file systems,
> sb->s_user_ns is also used in the quota code. The ACL code already does
> the conversion in a grotty layering violation in the VFS xattr code,
> so it keeps using init_user_ns for the identity mapping.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> fs/xfs/libxfs/xfs_inode_buf.c | 8 ++++----
> fs/xfs/xfs_acl.c | 12 ++++++++----
> fs/xfs/xfs_dquot.c | 4 ++--
> fs/xfs/xfs_inode_item.c | 4 ++--
> fs/xfs/xfs_itable.c | 4 ++--
> fs/xfs/xfs_linux.h | 26 --------------------------
> fs/xfs/xfs_qm.c | 23 +++++++++--------------
> 7 files changed, 27 insertions(+), 54 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c
> index bc72b575ceed..17e88a8c8353 100644
> --- a/fs/xfs/libxfs/xfs_inode_buf.c
> +++ b/fs/xfs/libxfs/xfs_inode_buf.c
> @@ -222,8 +222,8 @@ xfs_inode_from_disk(
> }
>
> to->di_format = from->di_format;
> - inode->i_uid = xfs_uid_to_kuid(be32_to_cpu(from->di_uid));
Hmm. I'm not up on my userns-fu, but right now this is effectively:
inode->i_uid = make_kuid(&init_user_ns, be32_to_cpu(from->di_uid));
> - inode->i_gid = xfs_gid_to_kgid(be32_to_cpu(from->di_gid));
> + i_uid_write(inode, be32_to_cpu(from->di_uid));
Whereas this is:
inode->i_uid = make_kuid(inode->i_sb->s_user_ns, be32_to_cpu(...));
What happens if s_user_ns != init_user_ns? Isn't this a behavior
change? Granted, it looks like many of the other filesystems use
i_uid_write so maybe we're the ones who are doing it wrong...?
> + i_gid_write(inode, be32_to_cpu(from->di_gid));
> to->di_flushiter = be16_to_cpu(from->di_flushiter);
>
> /*
> @@ -276,8 +276,8 @@ xfs_inode_to_disk(
>
> to->di_version = from->di_version;
> to->di_format = from->di_format;
> - to->di_uid = cpu_to_be32(xfs_kuid_to_uid(inode->i_uid));
> - to->di_gid = cpu_to_be32(xfs_kgid_to_gid(inode->i_gid));
> + to->di_uid = cpu_to_be32(i_uid_read(inode));
> + to->di_gid = cpu_to_be32(i_gid_read(inode));
> to->di_projid_lo = cpu_to_be16(from->di_projid & 0xffff);
> to->di_projid_hi = cpu_to_be16(from->di_projid >> 16);
>
> diff --git a/fs/xfs/xfs_acl.c b/fs/xfs/xfs_acl.c
> index cd743fad8478..e7314b525b19 100644
> --- a/fs/xfs/xfs_acl.c
> +++ b/fs/xfs/xfs_acl.c
> @@ -67,10 +67,12 @@ xfs_acl_from_disk(
>
> switch (acl_e->e_tag) {
> case ACL_USER:
> - acl_e->e_uid = xfs_uid_to_kuid(be32_to_cpu(ace->ae_id));
> + acl_e->e_uid = make_kuid(&init_user_ns,
> + be32_to_cpu(ace->ae_id));
And I'm assuming that the "gross layering violation in the vfs xattr
code" is why it's init_user_ns here?
--D
> break;
> case ACL_GROUP:
> - acl_e->e_gid = xfs_gid_to_kgid(be32_to_cpu(ace->ae_id));
> + acl_e->e_gid = make_kgid(&init_user_ns,
> + be32_to_cpu(ace->ae_id));
> break;
> case ACL_USER_OBJ:
> case ACL_GROUP_OBJ:
> @@ -103,10 +105,12 @@ xfs_acl_to_disk(struct xfs_acl *aclp, const struct posix_acl *acl)
> ace->ae_tag = cpu_to_be32(acl_e->e_tag);
> switch (acl_e->e_tag) {
> case ACL_USER:
> - ace->ae_id = cpu_to_be32(xfs_kuid_to_uid(acl_e->e_uid));
> + ace->ae_id = cpu_to_be32(
> + from_kuid(&init_user_ns, acl_e->e_uid));
> break;
> case ACL_GROUP:
> - ace->ae_id = cpu_to_be32(xfs_kgid_to_gid(acl_e->e_gid));
> + ace->ae_id = cpu_to_be32(
> + from_kgid(&init_user_ns, acl_e->e_gid));
> break;
> default:
> ace->ae_id = cpu_to_be32(ACL_UNDEFINED_ID);
> diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
> index 3579de9306c1..711376ca269f 100644
> --- a/fs/xfs/xfs_dquot.c
> +++ b/fs/xfs/xfs_dquot.c
> @@ -829,9 +829,9 @@ xfs_qm_id_for_quotatype(
> {
> switch (type) {
> case XFS_DQ_USER:
> - return xfs_kuid_to_uid(VFS_I(ip)->i_uid);
> + return i_uid_read(VFS_I(ip));
> case XFS_DQ_GROUP:
> - return xfs_kgid_to_gid(VFS_I(ip)->i_gid);
> + return i_gid_read(VFS_I(ip));
> case XFS_DQ_PROJ:
> return ip->i_d.di_projid;
> }
> diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c
> index 83d7914556ef..f021b55a0301 100644
> --- a/fs/xfs/xfs_inode_item.c
> +++ b/fs/xfs/xfs_inode_item.c
> @@ -308,8 +308,8 @@ xfs_inode_to_log_dinode(
>
> to->di_version = from->di_version;
> to->di_format = from->di_format;
> - to->di_uid = xfs_kuid_to_uid(inode->i_uid);
> - to->di_gid = xfs_kgid_to_gid(inode->i_gid);
> + to->di_uid = i_uid_read(inode);
> + to->di_gid = i_gid_read(inode);
> to->di_projid_lo = from->di_projid & 0xffff;
> to->di_projid_hi = from->di_projid >> 16;
>
> diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
> index 497db4160283..d10660469884 100644
> --- a/fs/xfs/xfs_itable.c
> +++ b/fs/xfs/xfs_itable.c
> @@ -86,8 +86,8 @@ xfs_bulkstat_one_int(
> */
> buf->bs_projectid = ip->i_d.di_projid;
> buf->bs_ino = ino;
> - buf->bs_uid = xfs_kuid_to_uid(inode->i_uid);
> - buf->bs_gid = xfs_kgid_to_gid(inode->i_gid);
> + buf->bs_uid = i_uid_read(inode);
> + buf->bs_gid = i_gid_read(inode);
> buf->bs_size = dic->di_size;
>
> buf->bs_nlink = inode->i_nlink;
> diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
> index 8738bb03f253..bc43cd98697b 100644
> --- a/fs/xfs/xfs_linux.h
> +++ b/fs/xfs/xfs_linux.h
> @@ -163,32 +163,6 @@ struct xstats {
>
> extern struct xstats xfsstats;
>
> -/* Kernel uid/gid conversion. These are used to convert to/from the on disk
> - * uid_t/gid_t types to the kuid_t/kgid_t types that the kernel uses internally.
> - * The conversion here is type only, the value will remain the same since we
> - * are converting to the init_user_ns. The uid is later mapped to a particular
> - * user namespace value when crossing the kernel/user boundary.
> - */
> -static inline uint32_t xfs_kuid_to_uid(kuid_t uid)
> -{
> - return from_kuid(&init_user_ns, uid);
> -}
> -
> -static inline kuid_t xfs_uid_to_kuid(uint32_t uid)
> -{
> - return make_kuid(&init_user_ns, uid);
> -}
> -
> -static inline uint32_t xfs_kgid_to_gid(kgid_t gid)
> -{
> - return from_kgid(&init_user_ns, gid);
> -}
> -
> -static inline kgid_t xfs_gid_to_kgid(uint32_t gid)
> -{
> - return make_kgid(&init_user_ns, gid);
> -}
> -
> static inline dev_t xfs_to_linux_dev_t(xfs_dev_t dev)
> {
> return MKDEV(sysv_major(dev) & 0x1ff, sysv_minor(dev));
> diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
> index 54dda7d982c9..de1d2c606c14 100644
> --- a/fs/xfs/xfs_qm.c
> +++ b/fs/xfs/xfs_qm.c
> @@ -326,8 +326,7 @@ xfs_qm_dqattach_locked(
> ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
>
> if (XFS_IS_UQUOTA_ON(mp) && !ip->i_udquot) {
> - error = xfs_qm_dqattach_one(ip,
> - xfs_kuid_to_uid(VFS_I(ip)->i_uid),
> + error = xfs_qm_dqattach_one(ip, i_uid_read(VFS_I(ip)),
> XFS_DQ_USER, doalloc, &ip->i_udquot);
> if (error)
> goto done;
> @@ -335,8 +334,7 @@ xfs_qm_dqattach_locked(
> }
>
> if (XFS_IS_GQUOTA_ON(mp) && !ip->i_gdquot) {
> - error = xfs_qm_dqattach_one(ip,
> - xfs_kgid_to_gid(VFS_I(ip)->i_gid),
> + error = xfs_qm_dqattach_one(ip, i_gid_read(VFS_I(ip)),
> XFS_DQ_GROUP, doalloc, &ip->i_gdquot);
> if (error)
> goto done;
> @@ -1625,6 +1623,7 @@ xfs_qm_vop_dqalloc(
> {
> struct xfs_mount *mp = ip->i_mount;
> struct inode *inode = VFS_I(ip);
> + struct user_namespace *user_ns = inode->i_sb->s_user_ns;
> struct xfs_dquot *uq = NULL;
> struct xfs_dquot *gq = NULL;
> struct xfs_dquot *pq = NULL;
> @@ -1664,7 +1663,7 @@ xfs_qm_vop_dqalloc(
> * holding ilock.
> */
> xfs_iunlock(ip, lockflags);
> - error = xfs_qm_dqget(mp, xfs_kuid_to_uid(uid),
> + error = xfs_qm_dqget(mp, from_kuid(user_ns, uid),
> XFS_DQ_USER, true, &uq);
> if (error) {
> ASSERT(error != -ENOENT);
> @@ -1688,7 +1687,7 @@ xfs_qm_vop_dqalloc(
> if ((flags & XFS_QMOPT_GQUOTA) && XFS_IS_GQUOTA_ON(mp)) {
> if (!gid_eq(inode->i_gid, gid)) {
> xfs_iunlock(ip, lockflags);
> - error = xfs_qm_dqget(mp, xfs_kgid_to_gid(gid),
> + error = xfs_qm_dqget(mp, from_kgid(user_ns, gid),
> XFS_DQ_GROUP, true, &gq);
> if (error) {
> ASSERT(error != -ENOENT);
> @@ -1815,8 +1814,7 @@ xfs_qm_vop_chown_reserve(
> XFS_QMOPT_RES_RTBLKS : XFS_QMOPT_RES_REGBLKS;
>
> if (XFS_IS_UQUOTA_ON(mp) && udqp &&
> - xfs_kuid_to_uid(VFS_I(ip)->i_uid) !=
> - be32_to_cpu(udqp->q_core.d_id)) {
> + i_uid_read(VFS_I(ip)) != be32_to_cpu(udqp->q_core.d_id)) {
> udq_delblks = udqp;
> /*
> * If there are delayed allocation blocks, then we have to
> @@ -1829,8 +1827,7 @@ xfs_qm_vop_chown_reserve(
> }
> }
> if (XFS_IS_GQUOTA_ON(ip->i_mount) && gdqp &&
> - xfs_kgid_to_gid(VFS_I(ip)->i_gid) !=
> - be32_to_cpu(gdqp->q_core.d_id)) {
> + i_gid_read(VFS_I(ip)) != be32_to_cpu(gdqp->q_core.d_id)) {
> gdq_delblks = gdqp;
> if (delblks) {
> ASSERT(ip->i_gdquot);
> @@ -1927,16 +1924,14 @@ xfs_qm_vop_create_dqattach(
>
> if (udqp && XFS_IS_UQUOTA_ON(mp)) {
> ASSERT(ip->i_udquot == NULL);
> - ASSERT(xfs_kuid_to_uid(VFS_I(ip)->i_uid) ==
> - be32_to_cpu(udqp->q_core.d_id));
> + ASSERT(i_uid_read(VFS_I(ip)) == be32_to_cpu(udqp->q_core.d_id));
>
> ip->i_udquot = xfs_qm_dqhold(udqp);
> xfs_trans_mod_dquot(tp, udqp, XFS_TRANS_DQ_ICOUNT, 1);
> }
> if (gdqp && XFS_IS_GQUOTA_ON(mp)) {
> ASSERT(ip->i_gdquot == NULL);
> - ASSERT(xfs_kgid_to_gid(VFS_I(ip)->i_gid) ==
> - be32_to_cpu(gdqp->q_core.d_id));
> + ASSERT(i_gid_read(VFS_I(ip)) == be32_to_cpu(gdqp->q_core.d_id));
>
> ip->i_gdquot = xfs_qm_dqhold(gdqp);
> xfs_trans_mod_dquot(tp, gdqp, XFS_TRANS_DQ_ICOUNT, 1);
> --
> 2.24.1
>
