ovl: use wrappers to all vfs_*xattr() calls

Use helpers ovl_*xattr() to access user/trusted.overlay.* xattrs
and use helpers ovl_do_*xattr() to access generic xattrs. This is a
preparatory patch for using idmapped base layers with overlay.

Note that a few of those places called vfs_*xattr() calls directly to
reduce the amount of debug output. But as Miklos pointed out since
overlayfs has been stable for quite some time the debug output isn't all
that relevant anymore and the additional debug in all locations was
actually quite helpful when developing this patch series.

Cc: <linux-unionfs@vger.kernel.org>
Tested-by: Giuseppe Scrivano <gscrivan@redhat.com>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index e040970408d4ff2b57c3e64518961eacbf66113a..fead5fd19c81c507fd1fa507c20406356005c6b0 100644 (file)
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -117,7 +117,7 @@ retry:
                        goto retry;
                }
 
-               error = vfs_setxattr(&init_user_ns, new, name, value, size, 0);
+               error = ovl_do_setxattr(OVL_FS(sb), new, name, value, size, 0);
                if (error) {
                        if (error != -EOPNOTSUPP || ovl_must_copy_xattr(name))
                                break;
@@ -433,7 +433,7 @@ static int ovl_set_upper_fh(struct ovl_fs *ofs, struct dentry *upper,
        if (IS_ERR(fh))
                return PTR_ERR(fh);
 
-       err = ovl_do_setxattr(ofs, index, OVL_XATTR_UPPER, fh->buf, fh->fb.len);
+       err = ovl_setxattr(ofs, index, OVL_XATTR_UPPER, fh->buf, fh->fb.len);
 
        kfree(fh);
        return err;
@@ -865,12 +865,13 @@ static bool ovl_need_meta_copy_up(struct dentry *dentry, umode_t mode,
        return true;
 }
 
-static ssize_t ovl_getxattr(struct dentry *dentry, char *name, char **value)
+static ssize_t ovl_getxattr_value(struct ovl_fs *ofs, struct dentry *dentry,
+                                 char *name, char **value)
 {
        ssize_t res;
        char *buf;
 
-       res = vfs_getxattr(&init_user_ns, dentry, name, NULL, 0);
+       res = ovl_do_getxattr(ofs, dentry, name, NULL, 0);
        if (res == -ENODATA || res == -EOPNOTSUPP)
                res = 0;
 
@@ -879,7 +880,7 @@ static ssize_t ovl_getxattr(struct dentry *dentry, char *name, char **value)
                if (!buf)
                        return -ENOMEM;
 
-               res = vfs_getxattr(&init_user_ns, dentry, name, buf, res);
+               res = ovl_do_getxattr(ofs, dentry, name, buf, res);
                if (res < 0)
                        kfree(buf);
                else
@@ -906,8 +907,8 @@ static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c)
                return -EIO;
 
        if (c->stat.size) {
-               err = cap_size = ovl_getxattr(upperpath.dentry, XATTR_NAME_CAPS,
-                                             &capability);
+               err = cap_size = ovl_getxattr_value(ofs, upperpath.dentry,
+                                                   XATTR_NAME_CAPS, &capability);
                if (cap_size < 0)
                        goto out;
        }
@@ -921,14 +922,14 @@ static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c)
         * don't want that to happen for normal copy-up operation.
         */
        if (capability) {
-               err = vfs_setxattr(&init_user_ns, upperpath.dentry,
-                                  XATTR_NAME_CAPS, capability, cap_size, 0);
+               err = ovl_do_setxattr(ofs, upperpath.dentry, XATTR_NAME_CAPS,
+                                     capability, cap_size, 0);
                if (err)
                        goto out_free;
        }
 
 
-       err = ovl_do_removexattr(ofs, upperpath.dentry, OVL_XATTR_METACOPY);
+       err = ovl_removexattr(ofs, upperpath.dentry, OVL_XATTR_METACOPY);
        if (err)
                goto out_free;
 

diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index f18490813170af41375c24360ba6e136a841b30a..8bf800c5796a9f60d3113f06cc05d73f5bf72c56 100644 (file)
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -432,8 +432,8 @@ out:
        return ERR_PTR(err);
 }
 
-static int ovl_set_upper_acl(struct dentry *upperdentry, const char *name,
-                            const struct posix_acl *acl)
+static int ovl_set_upper_acl(struct ovl_fs *ofs, struct dentry *upperdentry,
+                            const char *name, const struct posix_acl *acl)
 {
        void *buffer;
        size_t size;
@@ -451,7 +451,7 @@ static int ovl_set_upper_acl(struct dentry *upperdentry, const char *name,
        if (err < 0)
                goto out_free;
 
-       err = vfs_setxattr(&init_user_ns, upperdentry, name, buffer, size, XATTR_CREATE);
+       err = ovl_do_setxattr(ofs, upperdentry, name, buffer, size, XATTR_CREATE);
 out_free:
        kfree(buffer);
        return err;
@@ -460,6 +460,7 @@ out_free:
 static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
                                    struct ovl_cattr *cattr)
 {
+       struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
        struct dentry *workdir = ovl_workdir(dentry);
        struct inode *wdir = workdir->d_inode;
        struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
@@ -516,13 +517,13 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
                        goto out_cleanup;
        }
        if (!hardlink) {
-               err = ovl_set_upper_acl(newdentry, XATTR_NAME_POSIX_ACL_ACCESS,
-                                       acl);
+               err = ovl_set_upper_acl(ofs, newdentry,
+                                       XATTR_NAME_POSIX_ACL_ACCESS, acl);
                if (err)
                        goto out_cleanup;
 
-               err = ovl_set_upper_acl(newdentry, XATTR_NAME_POSIX_ACL_DEFAULT,
-                                       default_acl);
+               err = ovl_set_upper_acl(ofs, newdentry,
+                                       XATTR_NAME_POSIX_ACL_DEFAULT, default_acl);
                if (err)
                        goto out_cleanup;
        }

diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 1f36158c7dbe2f8782a2dcb6f15a4f0c4bbef28c..40210d6d451de0cc5f7113c64185acf7ce88d79c 100644 (file)
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -342,6 +342,7 @@ int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
                  const void *value, size_t size, int flags)
 {
        int err;
+       struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
        struct dentry *upperdentry = ovl_i_dentry_upper(inode);
        struct dentry *realdentry = upperdentry ?: ovl_dentry_lower(dentry);
        const struct cred *old_cred;
@@ -367,12 +368,12 @@ int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
        }
 
        old_cred = ovl_override_creds(dentry->d_sb);
-       if (value)
-               err = vfs_setxattr(&init_user_ns, realdentry, name, value, size,
-                                  flags);
-       else {
+       if (value) {
+               err = ovl_do_setxattr(ofs, realdentry, name, value, size,
+                                     flags);
+       } else {
                WARN_ON(flags != XATTR_REPLACE);
-               err = vfs_removexattr(&init_user_ns, realdentry, name);
+               err = ovl_do_removexattr(ofs, realdentry, name);
        }
        revert_creds(old_cred);
 
@@ -871,8 +872,8 @@ static int ovl_set_nlink_common(struct dentry *dentry,
        if (WARN_ON(len >= sizeof(buf)))
                return -EIO;
 
-       return ovl_do_setxattr(OVL_FS(inode->i_sb), ovl_dentry_upper(dentry),
-                              OVL_XATTR_NLINK, buf, len);
+       return ovl_setxattr(OVL_FS(inode->i_sb), ovl_dentry_upper(dentry),
+                           OVL_XATTR_NLINK, buf, len);
 }
 
 int ovl_set_nlink_upper(struct dentry *dentry)
@@ -897,7 +898,7 @@ unsigned int ovl_get_nlink(struct ovl_fs *ofs, struct dentry *lowerdentry,
        if (!lowerdentry || !upperdentry || d_inode(lowerdentry)->i_nlink == 1)
                return fallback;
 
-       err = ovl_do_getxattr(ofs, upperdentry, OVL_XATTR_NLINK,
+       err = ovl_getxattr(ofs, upperdentry, OVL_XATTR_NLINK,
                              &buf, sizeof(buf) - 1);
        if (err < 0)
                goto fail;

diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
index 1a9b515fc45d468bcd435931a99444aed9eca634..042f6394a3d502ffd89a68a40de0eebd8faa6717 100644 (file)
--- a/fs/overlayfs/namei.c
+++ b/fs/overlayfs/namei.c
@@ -111,7 +111,7 @@ static struct ovl_fh *ovl_get_fh(struct ovl_fs *ofs, struct dentry *dentry,
        int res, err;
        struct ovl_fh *fh = NULL;
 
-       res = ovl_do_getxattr(ofs, dentry, ox, NULL, 0);
+       res = ovl_getxattr(ofs, dentry, ox, NULL, 0);
        if (res < 0) {
                if (res == -ENODATA || res == -EOPNOTSUPP)
                        return NULL;
@@ -125,7 +125,7 @@ static struct ovl_fh *ovl_get_fh(struct ovl_fs *ofs, struct dentry *dentry,
        if (!fh)
                return ERR_PTR(-ENOMEM);
 
-       res = ovl_do_getxattr(ofs, dentry, ox, fh->buf, res);
+       res = ovl_getxattr(ofs, dentry, ox, fh->buf, res);
        if (res < 0)
                goto fail;
 
@@ -464,7 +464,7 @@ int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
 
        err = ovl_verify_fh(ofs, dentry, ox, fh);
        if (set && err == -ENODATA)
-               err = ovl_do_setxattr(ofs, dentry, ox, fh->buf, fh->fb.len);
+               err = ovl_setxattr(ofs, dentry, ox, fh->buf, fh->fb.len);
        if (err)
                goto fail;
 

diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 2cd5741c873b60592a139273017b669075bac72f..e6e30237d51ad49d3c15efb019cafa8291873b09 100644 (file)
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -183,10 +183,9 @@ static inline int ovl_do_symlink(struct inode *dir, struct dentry *dentry,
 }
 
 static inline ssize_t ovl_do_getxattr(struct ovl_fs *ofs, struct dentry *dentry,
-                                     enum ovl_xattr ox, void *value,
+                                     const char *name, void *value,
                                      size_t size)
 {
-       const char *name = ovl_xattr(ofs, ox);
        int err = vfs_getxattr(&init_user_ns, dentry, name, value, size);
        int len = (value && err > 0) ? err : 0;
 
@@ -195,26 +194,45 @@ static inline ssize_t ovl_do_getxattr(struct ovl_fs *ofs, struct dentry *dentry,
        return err;
 }
 
+static inline ssize_t ovl_getxattr(struct ovl_fs *ofs, struct dentry *dentry,
+                                  enum ovl_xattr ox, void *value,
+                                  size_t size)
+{
+       return ovl_do_getxattr(ofs, dentry, ovl_xattr(ofs, ox), value, size);
+}
+
 static inline int ovl_do_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
-                                 enum ovl_xattr ox, const void *value,
-                                 size_t size)
+                                 const char *name, const void *value,
+                                 size_t size, int flags)
 {
-       const char *name = ovl_xattr(ofs, ox);
-       int err = vfs_setxattr(&init_user_ns, dentry, name, value, size, 0);
-       pr_debug("setxattr(%pd2, \"%s\", \"%*pE\", %zu, 0) = %i\n",
-                dentry, name, min((int)size, 48), value, size, err);
+       int err = vfs_setxattr(&init_user_ns, dentry, name, value, size, flags);
+
+       pr_debug("setxattr(%pd2, \"%s\", \"%*pE\", %zu, %d) = %i\n",
+                dentry, name, min((int)size, 48), value, size, flags, err);
        return err;
 }
 
+static inline int ovl_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
+                              enum ovl_xattr ox, const void *value,
+                              size_t size)
+{
+       return ovl_do_setxattr(ofs, dentry, ovl_xattr(ofs, ox), value, size, 0);
+}
+
 static inline int ovl_do_removexattr(struct ovl_fs *ofs, struct dentry *dentry,
-                                    enum ovl_xattr ox)
+                                    const char *name)
 {
-       const char *name = ovl_xattr(ofs, ox);
        int err = vfs_removexattr(&init_user_ns, dentry, name);
        pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry, name, err);
        return err;
 }
 
+static inline int ovl_removexattr(struct ovl_fs *ofs, struct dentry *dentry,
+                                 enum ovl_xattr ox)
+{
+       return ovl_do_removexattr(ofs, dentry, ovl_xattr(ofs, ox));
+}
+
 static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry,
                                struct inode *newdir, struct dentry *newdentry,
                                unsigned int flags)

diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 150fdf3bc68d4c812fe45a886c724e58c56f84aa..c7b542331065c4325ee0c3a3ebb50bdaf9068bc9 100644 (file)
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -623,8 +623,8 @@ static struct ovl_dir_cache *ovl_cache_get_impure(struct path *path)
                 * Removing the "impure" xattr is best effort.
                 */
                if (!ovl_want_write(dentry)) {
-                       ovl_do_removexattr(ofs, ovl_dentry_upper(dentry),
-                                          OVL_XATTR_IMPURE);
+                       ovl_removexattr(ofs, ovl_dentry_upper(dentry),
+                                       OVL_XATTR_IMPURE);
                        ovl_drop_write(dentry);
                }
                ovl_clear_flag(OVL_IMPURE, d_inode(dentry));

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 001cdbb8f015212b3bf2ade964adaf82294954b1..7dd5dcdeeb65874ce350cf3662d7e142ce93567c 100644 (file)
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -809,13 +809,13 @@ retry:
                 * allowed as upper are limited to "normal" ones, where checking
                 * for the above two errors is sufficient.
                 */
-               err = vfs_removexattr(&init_user_ns, work,
-                                     XATTR_NAME_POSIX_ACL_DEFAULT);
+               err = ovl_do_removexattr(ofs, work,
+                                        XATTR_NAME_POSIX_ACL_DEFAULT);
                if (err && err != -ENODATA && err != -EOPNOTSUPP)
                        goto out_dput;
 
-               err = vfs_removexattr(&init_user_ns, work,
-                                     XATTR_NAME_POSIX_ACL_ACCESS);
+               err = ovl_do_removexattr(ofs, work,
+                                        XATTR_NAME_POSIX_ACL_ACCESS);
                if (err && err != -ENODATA && err != -EOPNOTSUPP)
                        goto out_dput;
 
@@ -1411,7 +1411,7 @@ static int ovl_make_workdir(struct super_block *sb, struct ovl_fs *ofs,
        /*
         * Check if upper/work fs supports (trusted|user).overlay.* xattr
         */
-       err = ovl_do_setxattr(ofs, ofs->workdir, OVL_XATTR_OPAQUE, "0", 1);
+       err = ovl_setxattr(ofs, ofs->workdir, OVL_XATTR_OPAQUE, "0", 1);
        if (err) {
                ofs->noxattr = true;
                if (ofs->config.index || ofs->config.metacopy) {
@@ -1429,7 +1429,7 @@ static int ovl_make_workdir(struct super_block *sb, struct ovl_fs *ofs,
                }
                err = 0;
        } else {
-               ovl_do_removexattr(ofs, ofs->workdir, OVL_XATTR_OPAQUE);
+               ovl_removexattr(ofs, ofs->workdir, OVL_XATTR_OPAQUE);
        }
 
        /*

diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index f48284a2a89600d32ef96ec600cdbc47b04781d4..453551f564673d2e0fa4c73652770cbb4de93e1d 100644 (file)
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -554,7 +554,7 @@ bool ovl_check_origin_xattr(struct ovl_fs *ofs, struct dentry *dentry)
 {
        int res;
 
-       res = ovl_do_getxattr(ofs, dentry, OVL_XATTR_ORIGIN, NULL, 0);
+       res = ovl_getxattr(ofs, dentry, OVL_XATTR_ORIGIN, NULL, 0);
 
        /* Zero size value means "copied up but origin unknown" */
        if (res >= 0)
@@ -572,7 +572,7 @@ bool ovl_check_dir_xattr(struct super_block *sb, struct dentry *dentry,
        if (!d_is_dir(dentry))
                return false;
 
-       res = ovl_do_getxattr(OVL_FS(sb), dentry, ox, &val, 1);
+       res = ovl_getxattr(OVL_FS(sb), dentry, ox, &val, 1);
        if (res == 1 && val == 'y')
                return true;
 
@@ -612,7 +612,7 @@ int ovl_check_setxattr(struct ovl_fs *ofs, struct dentry *upperdentry,
        if (ofs->noxattr)
                return xerr;
 
-       err = ovl_do_setxattr(ofs, upperdentry, ox, value, size);
+       err = ovl_setxattr(ofs, upperdentry, ox, value, size);
 
        if (err == -EOPNOTSUPP) {
                pr_warn("cannot set %s xattr on upper\n", ovl_xattr(ofs, ox));
@@ -652,7 +652,7 @@ void ovl_check_protattr(struct inode *inode, struct dentry *upper)
        char buf[OVL_PROTATTR_MAX+1];
        int res, n;
 
-       res = ovl_do_getxattr(ofs, upper, OVL_XATTR_PROTATTR, buf,
+       res = ovl_getxattr(ofs, upper, OVL_XATTR_PROTATTR, buf,
                              OVL_PROTATTR_MAX);
        if (res < 0)
                return;
@@ -708,7 +708,7 @@ int ovl_set_protattr(struct inode *inode, struct dentry *upper,
                err = ovl_check_setxattr(ofs, upper, OVL_XATTR_PROTATTR,
                                         buf, len, -EPERM);
        } else if (inode->i_flags & OVL_PROT_I_FLAGS_MASK) {
-               err = ovl_do_removexattr(ofs, upper, OVL_XATTR_PROTATTR);
+               err = ovl_removexattr(ofs, upper, OVL_XATTR_PROTATTR);
                if (err == -EOPNOTSUPP || err == -ENODATA)
                        err = 0;
        }
@@ -951,7 +951,7 @@ int ovl_check_metacopy_xattr(struct ovl_fs *ofs, struct dentry *dentry)
        if (!S_ISREG(d_inode(dentry)->i_mode))
                return 0;
 
-       res = ovl_do_getxattr(ofs, dentry, OVL_XATTR_METACOPY, NULL, 0);
+       res = ovl_getxattr(ofs, dentry, OVL_XATTR_METACOPY, NULL, 0);
        if (res < 0) {
                if (res == -ENODATA || res == -EOPNOTSUPP)
                        return 0;
@@ -993,7 +993,7 @@ char *ovl_get_redirect_xattr(struct ovl_fs *ofs, struct dentry *dentry,
        int res;
        char *s, *next, *buf = NULL;
 
-       res = ovl_do_getxattr(ofs, dentry, OVL_XATTR_REDIRECT, NULL, 0);
+       res = ovl_getxattr(ofs, dentry, OVL_XATTR_REDIRECT, NULL, 0);
        if (res == -ENODATA || res == -EOPNOTSUPP)
                return NULL;
        if (res < 0)
@@ -1005,7 +1005,7 @@ char *ovl_get_redirect_xattr(struct ovl_fs *ofs, struct dentry *dentry,
        if (!buf)
                return ERR_PTR(-ENOMEM);
 
-       res = ovl_do_getxattr(ofs, dentry, OVL_XATTR_REDIRECT, buf, res);
+       res = ovl_getxattr(ofs, dentry, OVL_XATTR_REDIRECT, buf, res);
        if (res < 0)
                goto fail;
        if (res == 0)