[PATCH] cifs: add mount option to encode xattr names as hexadecimal

[PATCH] cifs: add mount option to encode xattr names as hexadecimal

[Ronnie Sahlberg]

We store xattrs as Extended Attributes for SMB.
Some servers treat the EA names as case-insensitive as well as converting them to all upper-case.

This addresses that issue by adding a new mount option to convert all EA names to/from
hexadecimal representation.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
---
 fs/cifs/cifs_fs_sb.h |  1 +
 fs/cifs/cifsfs.c     |  3 +++
 fs/cifs/cifsglob.h   |  3 ++-
 fs/cifs/connect.c    |  7 +++++++
 fs/cifs/smb2ops.c    | 58 ++++++++++++++++++++++++++++++++++++++++------------
 5 files changed, 58 insertions(+), 14 deletions(-)

diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index ed49222abecb..11fb5f4d2b0e 100644
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -52,6 +52,7 @@
 #define CIFS_MOUNT_UID_FROM_ACL 0x2000000 /* try to get UID via special SID */
 #define CIFS_MOUNT_NO_HANDLE_CACHE 0x4000000 /* disable caching dir handles */
 #define CIFS_MOUNT_NO_DFS 0x8000000 /* disable DFS resolving */
+#define CIFS_MOUNT_ENCODED_XATTR  0x10000000 /* encode the xattr names */
 
 struct cifs_sb_info {
 	struct rb_root tlink_tree;
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index d06edebf3a73..c3c837ee3c4e 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -471,6 +471,9 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
 	else
 		seq_puts(s, ",noforcegid");
 
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_ENCODED_XATTR)
+		seq_puts(s, ",endodedxattr");
+
 	cifs_show_address(s, tcon->ses->server);
 
 	if (!tcon->unix_ext)
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 4777b3c4a92c..b479207f7f74 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -585,6 +585,7 @@ struct smb_vol {
 	bool resilient:1; /* noresilient not required since not fored for CA */
 	bool domainauto:1;
 	bool rdma:1;
+	bool encoded_xattr:1;
 	unsigned int bsize;
 	unsigned int rsize;
 	unsigned int wsize;
@@ -617,7 +618,7 @@ struct smb_vol {
 			 CIFS_MOUNT_FSCACHE | CIFS_MOUNT_MF_SYMLINKS | \
 			 CIFS_MOUNT_MULTIUSER | CIFS_MOUNT_STRICT_IO | \
 			 CIFS_MOUNT_CIFS_BACKUPUID | CIFS_MOUNT_CIFS_BACKUPGID | \
-			 CIFS_MOUNT_NO_DFS)
+			 CIFS_MOUNT_NO_DFS|CIFS_MOUNT_ENCODED_XATTR)
 
 /**
  * Generic VFS superblock mount flags (s_flags) to consider when
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 51f272377ae1..f955b28a9b38 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -97,6 +97,7 @@ enum {
 	Opt_persistent, Opt_nopersistent,
 	Opt_resilient, Opt_noresilient,
 	Opt_domainauto, Opt_rdma,
+	Opt_encodedxattr,
 
 	/* Mount options which take numeric value */
 	Opt_backupuid, Opt_backupgid, Opt_uid,
@@ -194,6 +195,7 @@ static const match_table_t cifs_mount_option_tokens = {
 	{ Opt_noresilient, "noresilienthandles"},
 	{ Opt_domainauto, "domainauto"},
 	{ Opt_rdma, "rdma"},
+	{ Opt_encodedxattr, "encodedxattr" },
 
 	{ Opt_backupuid, "backupuid=%s" },
 	{ Opt_backupgid, "backupgid=%s" },
@@ -1911,6 +1913,9 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
 		case Opt_rdma:
 			vol->rdma = true;
 			break;
+		case Opt_encodedxattr:
+			vol->encoded_xattr = 1;
+			break;
 
 		/* Numeric Values */
 		case Opt_backupuid:
@@ -3986,6 +3991,8 @@ int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_UID;
 	if (pvolume_info->override_gid)
 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_GID;
+	if (pvolume_info->encoded_xattr)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_ENCODED_XATTR;
 	if (pvolume_info->dynperm)
 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DYNPERM;
 	if (pvolume_info->fsc)
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 376577cc4159..e2684a6627bb 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -891,7 +891,8 @@ smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
 static ssize_t
 move_smb2_ea_to_cifs(char *dst, size_t dst_size,
 		     struct smb2_file_full_ea_info *src, size_t src_size,
-		     const unsigned char *ea_name)
+		     const unsigned char *ea_name,
+		     struct cifs_sb_info *cifs_sb)
 {
 	int rc = 0;
 	unsigned int ea_name_len = ea_name ? strlen(ea_name) : 0;
@@ -905,6 +906,18 @@ move_smb2_ea_to_cifs(char *dst, size_t dst_size,
 		value = &src->ea_data[src->ea_name_length + 1];
 		value_len = (size_t)le16_to_cpu(src->ea_value_length);
 
+		if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR) {
+			if (name_len & 0x01) {
+				rc = -EINVAL;
+				goto out;
+			}
+			name_len = name_len / 2;
+			if (hex2bin(name, name, name_len)) {
+				rc = -EINVAL;
+				goto out;
+			}
+		}
+
 		if (name_len == 0)
 			break;
 
@@ -1018,7 +1031,8 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
 	info = (struct smb2_file_full_ea_info *)(
 			le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
 	rc = move_smb2_ea_to_cifs(ea_data, buf_size, info,
-			le32_to_cpu(rsp->OutputBufferLength), ea_name);
+				  le32_to_cpu(rsp->OutputBufferLength),
+				  ea_name, cifs_sb);
 
  qeas_exit:
 	kfree(utf16_path);
@@ -1029,13 +1043,14 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
 
 static int
 smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
-	    const char *path, const char *ea_name, const void *ea_value,
+	    const char *path, const char *name, const void *ea_value,
 	    const __u16 ea_value_len, const struct nls_table *nls_codepage,
 	    struct cifs_sb_info *cifs_sb)
 {
 	struct cifs_ses *ses = tcon->ses;
 	__le16 *utf16_path = NULL;
-	int ea_name_len = strlen(ea_name);
+	char *ea_name = (char *)name;
+	int ea_name_len = strlen(name);
 	int flags = 0;
 	int len;
 	struct smb_rqst rqst[3];
@@ -1050,21 +1065,36 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
 	void *data[1];
 	struct smb2_file_full_ea_info *ea = NULL;
 	struct kvec close_iov[1];
-	int rc;
+	int i, rc;
+
+	memset(rqst, 0, sizeof(rqst));
+	resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
+	memset(rsp_iov, 0, sizeof(rsp_iov));
 
 	if (smb3_encryption_required(tcon))
 		flags |= CIFS_TRANSFORM_REQ;
 
-	if (ea_name_len > 255)
-		return -EINVAL;
+	/* Do we need to encode the name in hex ? */
+	if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR) {
+		ea_name = kzalloc(ea_name_len * 2 + 1, GFP_KERNEL);
+		if (ea_name == NULL) {
+			rc = -ENOMEM;
+			goto sea_exit;
+		}
+		bin2hex(ea_name, name, ea_name_len);
+		ea_name_len = 2 * ea_name_len;
+	}
 
-	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
-	if (!utf16_path)
-		return -ENOMEM;
+	if (ea_name_len > 255) {
+		rc = -EINVAL;
+		goto sea_exit;
+	}
 
-	memset(rqst, 0, sizeof(rqst));
-	resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
-	memset(rsp_iov, 0, sizeof(rsp_iov));
+	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
+	if (!utf16_path) {
+		rc = -ENOMEM;
+		goto sea_exit;
+	}
 
 	if (ses->server->ops->query_all_EAs) {
 		if (!ea_value) {
@@ -1137,6 +1167,8 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
 				resp_buftype, rsp_iov);
 
  sea_exit:
+	if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR)
+		kfree(ea_name);
 	kfree(ea);
 	kfree(utf16_path);
 	SMB2_open_free(&rqst[0]);
-- 
2.13.6

Re: [PATCH] cifs: add mount option to encode xattr names as hexadecimal

[Steve French]

Do you remember which xfstests this fixes?

Also any ideas on whether we still need a fix for deleting an empty or
nonexistent xattr?

On Thu, Jun 20, 2019 at 7:03 PM Ronnie Sahlberg <lsahlber@redhat.com> wrote:
>
> We store xattrs as Extended Attributes for SMB.
> Some servers treat the EA names as case-insensitive as well as converting them to all upper-case.
>
> This addresses that issue by adding a new mount option to convert all EA names to/from
> hexadecimal representation.
>
> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
> ---
>  fs/cifs/cifs_fs_sb.h |  1 +
>  fs/cifs/cifsfs.c     |  3 +++
>  fs/cifs/cifsglob.h   |  3 ++-
>  fs/cifs/connect.c    |  7 +++++++
>  fs/cifs/smb2ops.c    | 58 ++++++++++++++++++++++++++++++++++++++++------------
>  5 files changed, 58 insertions(+), 14 deletions(-)
>
> diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
> index ed49222abecb..11fb5f4d2b0e 100644
> --- a/fs/cifs/cifs_fs_sb.h
> +++ b/fs/cifs/cifs_fs_sb.h
> @@ -52,6 +52,7 @@
>  #define CIFS_MOUNT_UID_FROM_ACL 0x2000000 /* try to get UID via special SID */
>  #define CIFS_MOUNT_NO_HANDLE_CACHE 0x4000000 /* disable caching dir handles */
>  #define CIFS_MOUNT_NO_DFS 0x8000000 /* disable DFS resolving */
> +#define CIFS_MOUNT_ENCODED_XATTR  0x10000000 /* encode the xattr names */
>
>  struct cifs_sb_info {
>         struct rb_root tlink_tree;
> diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> index d06edebf3a73..c3c837ee3c4e 100644
> --- a/fs/cifs/cifsfs.c
> +++ b/fs/cifs/cifsfs.c
> @@ -471,6 +471,9 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
>         else
>                 seq_puts(s, ",noforcegid");
>
> +       if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_ENCODED_XATTR)
> +               seq_puts(s, ",endodedxattr");
> +
>         cifs_show_address(s, tcon->ses->server);
>
>         if (!tcon->unix_ext)
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index 4777b3c4a92c..b479207f7f74 100644
> --- a/fs/cifs/cifsglob.h
> +++ b/fs/cifs/cifsglob.h
> @@ -585,6 +585,7 @@ struct smb_vol {
>         bool resilient:1; /* noresilient not required since not fored for CA */
>         bool domainauto:1;
>         bool rdma:1;
> +       bool encoded_xattr:1;
>         unsigned int bsize;
>         unsigned int rsize;
>         unsigned int wsize;
> @@ -617,7 +618,7 @@ struct smb_vol {
>                          CIFS_MOUNT_FSCACHE | CIFS_MOUNT_MF_SYMLINKS | \
>                          CIFS_MOUNT_MULTIUSER | CIFS_MOUNT_STRICT_IO | \
>                          CIFS_MOUNT_CIFS_BACKUPUID | CIFS_MOUNT_CIFS_BACKUPGID | \
> -                        CIFS_MOUNT_NO_DFS)
> +                        CIFS_MOUNT_NO_DFS|CIFS_MOUNT_ENCODED_XATTR)
>
>  /**
>   * Generic VFS superblock mount flags (s_flags) to consider when
> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
> index 51f272377ae1..f955b28a9b38 100644
> --- a/fs/cifs/connect.c
> +++ b/fs/cifs/connect.c
> @@ -97,6 +97,7 @@ enum {
>         Opt_persistent, Opt_nopersistent,
>         Opt_resilient, Opt_noresilient,
>         Opt_domainauto, Opt_rdma,
> +       Opt_encodedxattr,
>
>         /* Mount options which take numeric value */
>         Opt_backupuid, Opt_backupgid, Opt_uid,
> @@ -194,6 +195,7 @@ static const match_table_t cifs_mount_option_tokens = {
>         { Opt_noresilient, "noresilienthandles"},
>         { Opt_domainauto, "domainauto"},
>         { Opt_rdma, "rdma"},
> +       { Opt_encodedxattr, "encodedxattr" },
>
>         { Opt_backupuid, "backupuid=%s" },
>         { Opt_backupgid, "backupgid=%s" },
> @@ -1911,6 +1913,9 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
>                 case Opt_rdma:
>                         vol->rdma = true;
>                         break;
> +               case Opt_encodedxattr:
> +                       vol->encoded_xattr = 1;
> +                       break;
>
>                 /* Numeric Values */
>                 case Opt_backupuid:
> @@ -3986,6 +3991,8 @@ int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
>                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_UID;
>         if (pvolume_info->override_gid)
>                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_GID;
> +       if (pvolume_info->encoded_xattr)
> +               cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_ENCODED_XATTR;
>         if (pvolume_info->dynperm)
>                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DYNPERM;
>         if (pvolume_info->fsc)
> diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
> index 376577cc4159..e2684a6627bb 100644
> --- a/fs/cifs/smb2ops.c
> +++ b/fs/cifs/smb2ops.c
> @@ -891,7 +891,8 @@ smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
>  static ssize_t
>  move_smb2_ea_to_cifs(char *dst, size_t dst_size,
>                      struct smb2_file_full_ea_info *src, size_t src_size,
> -                    const unsigned char *ea_name)
> +                    const unsigned char *ea_name,
> +                    struct cifs_sb_info *cifs_sb)
>  {
>         int rc = 0;
>         unsigned int ea_name_len = ea_name ? strlen(ea_name) : 0;
> @@ -905,6 +906,18 @@ move_smb2_ea_to_cifs(char *dst, size_t dst_size,
>                 value = &src->ea_data[src->ea_name_length + 1];
>                 value_len = (size_t)le16_to_cpu(src->ea_value_length);
>
> +               if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR) {
> +                       if (name_len & 0x01) {
> +                               rc = -EINVAL;
> +                               goto out;
> +                       }
> +                       name_len = name_len / 2;
> +                       if (hex2bin(name, name, name_len)) {
> +                               rc = -EINVAL;
> +                               goto out;
> +                       }
> +               }
> +
>                 if (name_len == 0)
>                         break;
>
> @@ -1018,7 +1031,8 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
>         info = (struct smb2_file_full_ea_info *)(
>                         le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
>         rc = move_smb2_ea_to_cifs(ea_data, buf_size, info,
> -                       le32_to_cpu(rsp->OutputBufferLength), ea_name);
> +                                 le32_to_cpu(rsp->OutputBufferLength),
> +                                 ea_name, cifs_sb);
>
>   qeas_exit:
>         kfree(utf16_path);
> @@ -1029,13 +1043,14 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
>
>  static int
>  smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
> -           const char *path, const char *ea_name, const void *ea_value,
> +           const char *path, const char *name, const void *ea_value,
>             const __u16 ea_value_len, const struct nls_table *nls_codepage,
>             struct cifs_sb_info *cifs_sb)
>  {
>         struct cifs_ses *ses = tcon->ses;
>         __le16 *utf16_path = NULL;
> -       int ea_name_len = strlen(ea_name);
> +       char *ea_name = (char *)name;
> +       int ea_name_len = strlen(name);
>         int flags = 0;
>         int len;
>         struct smb_rqst rqst[3];
> @@ -1050,21 +1065,36 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
>         void *data[1];
>         struct smb2_file_full_ea_info *ea = NULL;
>         struct kvec close_iov[1];
> -       int rc;
> +       int i, rc;
> +
> +       memset(rqst, 0, sizeof(rqst));
> +       resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
> +       memset(rsp_iov, 0, sizeof(rsp_iov));
>
>         if (smb3_encryption_required(tcon))
>                 flags |= CIFS_TRANSFORM_REQ;
>
> -       if (ea_name_len > 255)
> -               return -EINVAL;
> +       /* Do we need to encode the name in hex ? */
> +       if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR) {
> +               ea_name = kzalloc(ea_name_len * 2 + 1, GFP_KERNEL);
> +               if (ea_name == NULL) {
> +                       rc = -ENOMEM;
> +                       goto sea_exit;
> +               }
> +               bin2hex(ea_name, name, ea_name_len);
> +               ea_name_len = 2 * ea_name_len;
> +       }
>
> -       utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
> -       if (!utf16_path)
> -               return -ENOMEM;
> +       if (ea_name_len > 255) {
> +               rc = -EINVAL;
> +               goto sea_exit;
> +       }
>
> -       memset(rqst, 0, sizeof(rqst));
> -       resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
> -       memset(rsp_iov, 0, sizeof(rsp_iov));
> +       utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
> +       if (!utf16_path) {
> +               rc = -ENOMEM;
> +               goto sea_exit;
> +       }
>
>         if (ses->server->ops->query_all_EAs) {
>                 if (!ea_value) {
> @@ -1137,6 +1167,8 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
>                                 resp_buftype, rsp_iov);
>
>   sea_exit:
> +       if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR)
> +               kfree(ea_name);
>         kfree(ea);
>         kfree(utf16_path);
>         SMB2_open_free(&rqst[0]);
> --
> 2.13.6
>


-- 
Thanks,

Steve

Re: [PATCH] cifs: add mount option to encode xattr names as hexadecimal

[ronnie sahlberg]

On Fri, Jun 21, 2019 at 10:20 AM Steve French <smfrench@gmail.com> wrote:
>
> Do you remember which xfstests this fixes?

I will take a look. As far as I remember we do run all those affected
xfstests in the buildbot.
I just pointed the failing tests to one of the samba hosts instead of
the default win2016 test server.

>
> Also any ideas on whether we still need a fix for deleting an empty or
> nonexistent xattr?

I think these bugs are already fixed in the current tree. At least for SMB2+.

>
> On Thu, Jun 20, 2019 at 7:03 PM Ronnie Sahlberg <lsahlber@redhat.com> wrote:
> >
> > We store xattrs as Extended Attributes for SMB.
> > Some servers treat the EA names as case-insensitive as well as converting them to all upper-case.
> >
> > This addresses that issue by adding a new mount option to convert all EA names to/from
> > hexadecimal representation.
> >
> > Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
> > ---
> >  fs/cifs/cifs_fs_sb.h |  1 +
> >  fs/cifs/cifsfs.c     |  3 +++
> >  fs/cifs/cifsglob.h   |  3 ++-
> >  fs/cifs/connect.c    |  7 +++++++
> >  fs/cifs/smb2ops.c    | 58 ++++++++++++++++++++++++++++++++++++++++------------
> >  5 files changed, 58 insertions(+), 14 deletions(-)
> >
> > diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
> > index ed49222abecb..11fb5f4d2b0e 100644
> > --- a/fs/cifs/cifs_fs_sb.h
> > +++ b/fs/cifs/cifs_fs_sb.h
> > @@ -52,6 +52,7 @@
> >  #define CIFS_MOUNT_UID_FROM_ACL 0x2000000 /* try to get UID via special SID */
> >  #define CIFS_MOUNT_NO_HANDLE_CACHE 0x4000000 /* disable caching dir handles */
> >  #define CIFS_MOUNT_NO_DFS 0x8000000 /* disable DFS resolving */
> > +#define CIFS_MOUNT_ENCODED_XATTR  0x10000000 /* encode the xattr names */
> >
> >  struct cifs_sb_info {
> >         struct rb_root tlink_tree;
> > diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> > index d06edebf3a73..c3c837ee3c4e 100644
> > --- a/fs/cifs/cifsfs.c
> > +++ b/fs/cifs/cifsfs.c
> > @@ -471,6 +471,9 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
> >         else
> >                 seq_puts(s, ",noforcegid");
> >
> > +       if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_ENCODED_XATTR)
> > +               seq_puts(s, ",endodedxattr");
> > +
> >         cifs_show_address(s, tcon->ses->server);
> >
> >         if (!tcon->unix_ext)
> > diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> > index 4777b3c4a92c..b479207f7f74 100644
> > --- a/fs/cifs/cifsglob.h
> > +++ b/fs/cifs/cifsglob.h
> > @@ -585,6 +585,7 @@ struct smb_vol {
> >         bool resilient:1; /* noresilient not required since not fored for CA */
> >         bool domainauto:1;
> >         bool rdma:1;
> > +       bool encoded_xattr:1;
> >         unsigned int bsize;
> >         unsigned int rsize;
> >         unsigned int wsize;
> > @@ -617,7 +618,7 @@ struct smb_vol {
> >                          CIFS_MOUNT_FSCACHE | CIFS_MOUNT_MF_SYMLINKS | \
> >                          CIFS_MOUNT_MULTIUSER | CIFS_MOUNT_STRICT_IO | \
> >                          CIFS_MOUNT_CIFS_BACKUPUID | CIFS_MOUNT_CIFS_BACKUPGID | \
> > -                        CIFS_MOUNT_NO_DFS)
> > +                        CIFS_MOUNT_NO_DFS|CIFS_MOUNT_ENCODED_XATTR)
> >
> >  /**
> >   * Generic VFS superblock mount flags (s_flags) to consider when
> > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
> > index 51f272377ae1..f955b28a9b38 100644
> > --- a/fs/cifs/connect.c
> > +++ b/fs/cifs/connect.c
> > @@ -97,6 +97,7 @@ enum {
> >         Opt_persistent, Opt_nopersistent,
> >         Opt_resilient, Opt_noresilient,
> >         Opt_domainauto, Opt_rdma,
> > +       Opt_encodedxattr,
> >
> >         /* Mount options which take numeric value */
> >         Opt_backupuid, Opt_backupgid, Opt_uid,
> > @@ -194,6 +195,7 @@ static const match_table_t cifs_mount_option_tokens = {
> >         { Opt_noresilient, "noresilienthandles"},
> >         { Opt_domainauto, "domainauto"},
> >         { Opt_rdma, "rdma"},
> > +       { Opt_encodedxattr, "encodedxattr" },
> >
> >         { Opt_backupuid, "backupuid=%s" },
> >         { Opt_backupgid, "backupgid=%s" },
> > @@ -1911,6 +1913,9 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
> >                 case Opt_rdma:
> >                         vol->rdma = true;
> >                         break;
> > +               case Opt_encodedxattr:
> > +                       vol->encoded_xattr = 1;
> > +                       break;
> >
> >                 /* Numeric Values */
> >                 case Opt_backupuid:
> > @@ -3986,6 +3991,8 @@ int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
> >                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_UID;
> >         if (pvolume_info->override_gid)
> >                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_GID;
> > +       if (pvolume_info->encoded_xattr)
> > +               cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_ENCODED_XATTR;
> >         if (pvolume_info->dynperm)
> >                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DYNPERM;
> >         if (pvolume_info->fsc)
> > diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
> > index 376577cc4159..e2684a6627bb 100644
> > --- a/fs/cifs/smb2ops.c
> > +++ b/fs/cifs/smb2ops.c
> > @@ -891,7 +891,8 @@ smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
> >  static ssize_t
> >  move_smb2_ea_to_cifs(char *dst, size_t dst_size,
> >                      struct smb2_file_full_ea_info *src, size_t src_size,
> > -                    const unsigned char *ea_name)
> > +                    const unsigned char *ea_name,
> > +                    struct cifs_sb_info *cifs_sb)
> >  {
> >         int rc = 0;
> >         unsigned int ea_name_len = ea_name ? strlen(ea_name) : 0;
> > @@ -905,6 +906,18 @@ move_smb2_ea_to_cifs(char *dst, size_t dst_size,
> >                 value = &src->ea_data[src->ea_name_length + 1];
> >                 value_len = (size_t)le16_to_cpu(src->ea_value_length);
> >
> > +               if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR) {
> > +                       if (name_len & 0x01) {
> > +                               rc = -EINVAL;
> > +                               goto out;
> > +                       }
> > +                       name_len = name_len / 2;
> > +                       if (hex2bin(name, name, name_len)) {
> > +                               rc = -EINVAL;
> > +                               goto out;
> > +                       }
> > +               }
> > +
> >                 if (name_len == 0)
> >                         break;
> >
> > @@ -1018,7 +1031,8 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
> >         info = (struct smb2_file_full_ea_info *)(
> >                         le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
> >         rc = move_smb2_ea_to_cifs(ea_data, buf_size, info,
> > -                       le32_to_cpu(rsp->OutputBufferLength), ea_name);
> > +                                 le32_to_cpu(rsp->OutputBufferLength),
> > +                                 ea_name, cifs_sb);
> >
> >   qeas_exit:
> >         kfree(utf16_path);
> > @@ -1029,13 +1043,14 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
> >
> >  static int
> >  smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
> > -           const char *path, const char *ea_name, const void *ea_value,
> > +           const char *path, const char *name, const void *ea_value,
> >             const __u16 ea_value_len, const struct nls_table *nls_codepage,
> >             struct cifs_sb_info *cifs_sb)
> >  {
> >         struct cifs_ses *ses = tcon->ses;
> >         __le16 *utf16_path = NULL;
> > -       int ea_name_len = strlen(ea_name);
> > +       char *ea_name = (char *)name;
> > +       int ea_name_len = strlen(name);
> >         int flags = 0;
> >         int len;
> >         struct smb_rqst rqst[3];
> > @@ -1050,21 +1065,36 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
> >         void *data[1];
> >         struct smb2_file_full_ea_info *ea = NULL;
> >         struct kvec close_iov[1];
> > -       int rc;
> > +       int i, rc;
> > +
> > +       memset(rqst, 0, sizeof(rqst));
> > +       resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
> > +       memset(rsp_iov, 0, sizeof(rsp_iov));
> >
> >         if (smb3_encryption_required(tcon))
> >                 flags |= CIFS_TRANSFORM_REQ;
> >
> > -       if (ea_name_len > 255)
> > -               return -EINVAL;
> > +       /* Do we need to encode the name in hex ? */
> > +       if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR) {
> > +               ea_name = kzalloc(ea_name_len * 2 + 1, GFP_KERNEL);
> > +               if (ea_name == NULL) {
> > +                       rc = -ENOMEM;
> > +                       goto sea_exit;
> > +               }
> > +               bin2hex(ea_name, name, ea_name_len);
> > +               ea_name_len = 2 * ea_name_len;
> > +       }
> >
> > -       utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
> > -       if (!utf16_path)
> > -               return -ENOMEM;
> > +       if (ea_name_len > 255) {
> > +               rc = -EINVAL;
> > +               goto sea_exit;
> > +       }
> >
> > -       memset(rqst, 0, sizeof(rqst));
> > -       resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
> > -       memset(rsp_iov, 0, sizeof(rsp_iov));
> > +       utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
> > +       if (!utf16_path) {
> > +               rc = -ENOMEM;
> > +               goto sea_exit;
> > +       }
> >
> >         if (ses->server->ops->query_all_EAs) {
> >                 if (!ea_value) {
> > @@ -1137,6 +1167,8 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
> >                                 resp_buftype, rsp_iov);
> >
> >   sea_exit:
> > +       if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR)
> > +               kfree(ea_name);
> >         kfree(ea);
> >         kfree(utf16_path);
> >         SMB2_open_free(&rqst[0]);
> > --
> > 2.13.6
> >
>
>
> --
> Thanks,
>
> Steve

Re: [PATCH] cifs: add mount option to encode xattr names as hexadecimal

[Steve French]

[-- Attachment #1: Type: text/plain, Size: 9161 bytes --]

Updated patch to fix minor compile warning and to rebase it on current for-next


On Thu, Jun 20, 2019 at 7:03 PM Ronnie Sahlberg <lsahlber@redhat.com> wrote:
>
> We store xattrs as Extended Attributes for SMB.
> Some servers treat the EA names as case-insensitive as well as converting them to all upper-case.
>
> This addresses that issue by adding a new mount option to convert all EA names to/from
> hexadecimal representation.
>
> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
> ---
>  fs/cifs/cifs_fs_sb.h |  1 +
>  fs/cifs/cifsfs.c     |  3 +++
>  fs/cifs/cifsglob.h   |  3 ++-
>  fs/cifs/connect.c    |  7 +++++++
>  fs/cifs/smb2ops.c    | 58 ++++++++++++++++++++++++++++++++++++++++------------
>  5 files changed, 58 insertions(+), 14 deletions(-)
>
> diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
> index ed49222abecb..11fb5f4d2b0e 100644
> --- a/fs/cifs/cifs_fs_sb.h
> +++ b/fs/cifs/cifs_fs_sb.h
> @@ -52,6 +52,7 @@
>  #define CIFS_MOUNT_UID_FROM_ACL 0x2000000 /* try to get UID via special SID */
>  #define CIFS_MOUNT_NO_HANDLE_CACHE 0x4000000 /* disable caching dir handles */
>  #define CIFS_MOUNT_NO_DFS 0x8000000 /* disable DFS resolving */
> +#define CIFS_MOUNT_ENCODED_XATTR  0x10000000 /* encode the xattr names */
>
>  struct cifs_sb_info {
>         struct rb_root tlink_tree;
> diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> index d06edebf3a73..c3c837ee3c4e 100644
> --- a/fs/cifs/cifsfs.c
> +++ b/fs/cifs/cifsfs.c
> @@ -471,6 +471,9 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
>         else
>                 seq_puts(s, ",noforcegid");
>
> +       if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_ENCODED_XATTR)
> +               seq_puts(s, ",endodedxattr");
> +
>         cifs_show_address(s, tcon->ses->server);
>
>         if (!tcon->unix_ext)
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index 4777b3c4a92c..b479207f7f74 100644
> --- a/fs/cifs/cifsglob.h
> +++ b/fs/cifs/cifsglob.h
> @@ -585,6 +585,7 @@ struct smb_vol {
>         bool resilient:1; /* noresilient not required since not fored for CA */
>         bool domainauto:1;
>         bool rdma:1;
> +       bool encoded_xattr:1;
>         unsigned int bsize;
>         unsigned int rsize;
>         unsigned int wsize;
> @@ -617,7 +618,7 @@ struct smb_vol {
>                          CIFS_MOUNT_FSCACHE | CIFS_MOUNT_MF_SYMLINKS | \
>                          CIFS_MOUNT_MULTIUSER | CIFS_MOUNT_STRICT_IO | \
>                          CIFS_MOUNT_CIFS_BACKUPUID | CIFS_MOUNT_CIFS_BACKUPGID | \
> -                        CIFS_MOUNT_NO_DFS)
> +                        CIFS_MOUNT_NO_DFS|CIFS_MOUNT_ENCODED_XATTR)
>
>  /**
>   * Generic VFS superblock mount flags (s_flags) to consider when
> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
> index 51f272377ae1..f955b28a9b38 100644
> --- a/fs/cifs/connect.c
> +++ b/fs/cifs/connect.c
> @@ -97,6 +97,7 @@ enum {
>         Opt_persistent, Opt_nopersistent,
>         Opt_resilient, Opt_noresilient,
>         Opt_domainauto, Opt_rdma,
> +       Opt_encodedxattr,
>
>         /* Mount options which take numeric value */
>         Opt_backupuid, Opt_backupgid, Opt_uid,
> @@ -194,6 +195,7 @@ static const match_table_t cifs_mount_option_tokens = {
>         { Opt_noresilient, "noresilienthandles"},
>         { Opt_domainauto, "domainauto"},
>         { Opt_rdma, "rdma"},
> +       { Opt_encodedxattr, "encodedxattr" },
>
>         { Opt_backupuid, "backupuid=%s" },
>         { Opt_backupgid, "backupgid=%s" },
> @@ -1911,6 +1913,9 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
>                 case Opt_rdma:
>                         vol->rdma = true;
>                         break;
> +               case Opt_encodedxattr:
> +                       vol->encoded_xattr = 1;
> +                       break;
>
>                 /* Numeric Values */
>                 case Opt_backupuid:
> @@ -3986,6 +3991,8 @@ int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
>                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_UID;
>         if (pvolume_info->override_gid)
>                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_GID;
> +       if (pvolume_info->encoded_xattr)
> +               cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_ENCODED_XATTR;
>         if (pvolume_info->dynperm)
>                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DYNPERM;
>         if (pvolume_info->fsc)
> diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
> index 376577cc4159..e2684a6627bb 100644
> --- a/fs/cifs/smb2ops.c
> +++ b/fs/cifs/smb2ops.c
> @@ -891,7 +891,8 @@ smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
>  static ssize_t
>  move_smb2_ea_to_cifs(char *dst, size_t dst_size,
>                      struct smb2_file_full_ea_info *src, size_t src_size,
> -                    const unsigned char *ea_name)
> +                    const unsigned char *ea_name,
> +                    struct cifs_sb_info *cifs_sb)
>  {
>         int rc = 0;
>         unsigned int ea_name_len = ea_name ? strlen(ea_name) : 0;
> @@ -905,6 +906,18 @@ move_smb2_ea_to_cifs(char *dst, size_t dst_size,
>                 value = &src->ea_data[src->ea_name_length + 1];
>                 value_len = (size_t)le16_to_cpu(src->ea_value_length);
>
> +               if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR) {
> +                       if (name_len & 0x01) {
> +                               rc = -EINVAL;
> +                               goto out;
> +                       }
> +                       name_len = name_len / 2;
> +                       if (hex2bin(name, name, name_len)) {
> +                               rc = -EINVAL;
> +                               goto out;
> +                       }
> +               }
> +
>                 if (name_len == 0)
>                         break;
>
> @@ -1018,7 +1031,8 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
>         info = (struct smb2_file_full_ea_info *)(
>                         le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
>         rc = move_smb2_ea_to_cifs(ea_data, buf_size, info,
> -                       le32_to_cpu(rsp->OutputBufferLength), ea_name);
> +                                 le32_to_cpu(rsp->OutputBufferLength),
> +                                 ea_name, cifs_sb);
>
>   qeas_exit:
>         kfree(utf16_path);
> @@ -1029,13 +1043,14 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
>
>  static int
>  smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
> -           const char *path, const char *ea_name, const void *ea_value,
> +           const char *path, const char *name, const void *ea_value,
>             const __u16 ea_value_len, const struct nls_table *nls_codepage,
>             struct cifs_sb_info *cifs_sb)
>  {
>         struct cifs_ses *ses = tcon->ses;
>         __le16 *utf16_path = NULL;
> -       int ea_name_len = strlen(ea_name);
> +       char *ea_name = (char *)name;
> +       int ea_name_len = strlen(name);
>         int flags = 0;
>         int len;
>         struct smb_rqst rqst[3];
> @@ -1050,21 +1065,36 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
>         void *data[1];
>         struct smb2_file_full_ea_info *ea = NULL;
>         struct kvec close_iov[1];
> -       int rc;
> +       int i, rc;
> +
> +       memset(rqst, 0, sizeof(rqst));
> +       resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
> +       memset(rsp_iov, 0, sizeof(rsp_iov));
>
>         if (smb3_encryption_required(tcon))
>                 flags |= CIFS_TRANSFORM_REQ;
>
> -       if (ea_name_len > 255)
> -               return -EINVAL;
> +       /* Do we need to encode the name in hex ? */
> +       if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR) {
> +               ea_name = kzalloc(ea_name_len * 2 + 1, GFP_KERNEL);
> +               if (ea_name == NULL) {
> +                       rc = -ENOMEM;
> +                       goto sea_exit;
> +               }
> +               bin2hex(ea_name, name, ea_name_len);
> +               ea_name_len = 2 * ea_name_len;
> +       }
>
> -       utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
> -       if (!utf16_path)
> -               return -ENOMEM;
> +       if (ea_name_len > 255) {
> +               rc = -EINVAL;
> +               goto sea_exit;
> +       }
>
> -       memset(rqst, 0, sizeof(rqst));
> -       resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
> -       memset(rsp_iov, 0, sizeof(rsp_iov));
> +       utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
> +       if (!utf16_path) {
> +               rc = -ENOMEM;
> +               goto sea_exit;
> +       }
>
>         if (ses->server->ops->query_all_EAs) {
>                 if (!ea_value) {
> @@ -1137,6 +1167,8 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
>                                 resp_buftype, rsp_iov);
>
>   sea_exit:
> +       if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR)
> +               kfree(ea_name);
>         kfree(ea);
>         kfree(utf16_path);
>         SMB2_open_free(&rqst[0]);
> --
> 2.13.6
>


-- 
Thanks,

Steve

[-- Attachment #2: 0005-smb3-add-mount-option-to-encode-xattr-names-as-hexad.patch --]
[-- Type: text/x-patch, Size: 7491 bytes --]

From 8ee52a8ad1dabc3e4802cfb064a0025c2cd0eec6 Mon Sep 17 00:00:00 2001
From: Ronnie Sahlberg <lsahlber@redhat.com>
Date: Tue, 16 Jul 2019 00:25:16 -0500
Subject: [PATCH 5/5] smb3: add mount option to encode xattr names as
 hexadecimal

We store xattrs as Extended Attributes for SMB.
Some servers treat the EA names as case-insensitive as well
as converting them to all upper-case.

This addresses that issue by adding a new mount option to convert
all EA names to/from hexadecimal representation.

Fixes xfstest generic/533 to Windows servers

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
---
 fs/cifs/cifs_fs_sb.h |  1 +
 fs/cifs/cifsfs.c     |  3 +++
 fs/cifs/cifsglob.h   |  4 +++-
 fs/cifs/connect.c    |  8 ++++++-
 fs/cifs/smb2ops.c    | 56 ++++++++++++++++++++++++++++++++++----------
 5 files changed, 58 insertions(+), 14 deletions(-)

diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index b326d2ca3765..90e2192daeff 100644
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -53,6 +53,7 @@
 #define CIFS_MOUNT_NO_HANDLE_CACHE 0x4000000 /* disable caching dir handles */
 #define CIFS_MOUNT_NO_DFS 0x8000000 /* disable DFS resolving */
 #define CIFS_MOUNT_MODE_FROM_SID 0x10000000 /* retrieve mode from special ACE */
+#define CIFS_MOUNT_ENCODED_XATTR 0x20000000 /* encode the xattr names */
 
 struct cifs_sb_info {
 	struct rb_root tlink_tree;
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 0ee63ac4ef72..320c7a6fd318 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -471,6 +471,9 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
 	else
 		seq_puts(s, ",noforcegid");
 
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_ENCODED_XATTR)
+		seq_puts(s, ",endodedxattr");
+
 	cifs_show_address(s, tcon->ses->server);
 
 	if (!tcon->unix_ext)
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index fe610e7e3670..8c7ea733947b 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -586,6 +586,7 @@ struct smb_vol {
 	bool resilient:1; /* noresilient not required since not fored for CA */
 	bool domainauto:1;
 	bool rdma:1;
+	bool encoded_xattr:1;
 	unsigned int bsize;
 	unsigned int rsize;
 	unsigned int wsize;
@@ -620,7 +621,8 @@ struct smb_vol {
 			 CIFS_MOUNT_MULTIUSER | CIFS_MOUNT_STRICT_IO | \
 			 CIFS_MOUNT_CIFS_BACKUPUID | CIFS_MOUNT_CIFS_BACKUPGID | \
 			 CIFS_MOUNT_UID_FROM_ACL | CIFS_MOUNT_NO_HANDLE_CACHE | \
-			 CIFS_MOUNT_NO_DFS | CIFS_MOUNT_MODE_FROM_SID)
+			 CIFS_MOUNT_NO_DFS | CIFS_MOUNT_MODE_FROM_SID | \
+			 CIFS_MOUNT_ENCODED_XATTR)
 
 /**
  * Generic VFS superblock mount flags (s_flags) to consider when
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 6331c4f93b59..35dfc412370b 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -97,7 +97,7 @@ enum {
 	Opt_persistent, Opt_nopersistent,
 	Opt_resilient, Opt_noresilient,
 	Opt_domainauto, Opt_rdma, Opt_modesid,
-	Opt_compress,
+	Opt_compress, Opt_encodedxattr,
 
 	/* Mount options which take numeric value */
 	Opt_backupuid, Opt_backupgid, Opt_uid,
@@ -196,6 +196,7 @@ static const match_table_t cifs_mount_option_tokens = {
 	{ Opt_noresilient, "noresilienthandles"},
 	{ Opt_domainauto, "domainauto"},
 	{ Opt_rdma, "rdma"},
+	{ Opt_encodedxattr, "encodedxattr" },
 
 	{ Opt_backupuid, "backupuid=%s" },
 	{ Opt_backupgid, "backupgid=%s" },
@@ -1922,6 +1923,9 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
 			cifs_dbg(VFS,
 				"SMB3 compression support is experimental\n");
 			break;
+		case Opt_encodedxattr:
+			vol->encoded_xattr = 1;
+			break;
 
 		/* Numeric Values */
 		case Opt_backupuid:
@@ -4004,6 +4008,8 @@ int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_UID;
 	if (pvolume_info->override_gid)
 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_GID;
+	if (pvolume_info->encoded_xattr)
+		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_ENCODED_XATTR;
 	if (pvolume_info->dynperm)
 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DYNPERM;
 	if (pvolume_info->fsc)
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 0cdc4e47ca87..6cb4def11ebe 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -878,7 +878,8 @@ smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
 static ssize_t
 move_smb2_ea_to_cifs(char *dst, size_t dst_size,
 		     struct smb2_file_full_ea_info *src, size_t src_size,
-		     const unsigned char *ea_name)
+		     const unsigned char *ea_name,
+		     struct cifs_sb_info *cifs_sb)
 {
 	int rc = 0;
 	unsigned int ea_name_len = ea_name ? strlen(ea_name) : 0;
@@ -892,6 +893,18 @@ move_smb2_ea_to_cifs(char *dst, size_t dst_size,
 		value = &src->ea_data[src->ea_name_length + 1];
 		value_len = (size_t)le16_to_cpu(src->ea_value_length);
 
+		if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR) {
+			if (name_len & 0x01) {
+				rc = -EINVAL;
+				goto out;
+			}
+			name_len = name_len / 2;
+			if (hex2bin(name, name, name_len)) {
+				rc = -EINVAL;
+				goto out;
+			}
+		}
+
 		if (name_len == 0)
 			break;
 
@@ -1005,7 +1018,8 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
 	info = (struct smb2_file_full_ea_info *)(
 			le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
 	rc = move_smb2_ea_to_cifs(ea_data, buf_size, info,
-			le32_to_cpu(rsp->OutputBufferLength), ea_name);
+				  le32_to_cpu(rsp->OutputBufferLength),
+				  ea_name, cifs_sb);
 
  qeas_exit:
 	kfree(utf16_path);
@@ -1016,13 +1030,14 @@ smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
 
 static int
 smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
-	    const char *path, const char *ea_name, const void *ea_value,
+	    const char *path, const char *name, const void *ea_value,
 	    const __u16 ea_value_len, const struct nls_table *nls_codepage,
 	    struct cifs_sb_info *cifs_sb)
 {
 	struct cifs_ses *ses = tcon->ses;
 	__le16 *utf16_path = NULL;
-	int ea_name_len = strlen(ea_name);
+	char *ea_name = (char *)name;
+	int ea_name_len = strlen(name);
 	int flags = 0;
 	int len;
 	struct smb_rqst rqst[3];
@@ -1039,19 +1054,34 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
 	struct kvec close_iov[1];
 	int rc;
 
+	memset(rqst, 0, sizeof(rqst));
+	resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
+	memset(rsp_iov, 0, sizeof(rsp_iov));
+
 	if (smb3_encryption_required(tcon))
 		flags |= CIFS_TRANSFORM_REQ;
 
-	if (ea_name_len > 255)
-		return -EINVAL;
+	/* Do we need to encode the name in hex ? */
+	if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR) {
+		ea_name = kzalloc(ea_name_len * 2 + 1, GFP_KERNEL);
+		if (ea_name == NULL) {
+			rc = -ENOMEM;
+			goto sea_exit;
+		}
+		bin2hex(ea_name, name, ea_name_len);
+		ea_name_len = 2 * ea_name_len;
+	}
 
-	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
-	if (!utf16_path)
-		return -ENOMEM;
+	if (ea_name_len > 255) {
+		rc = -EINVAL;
+		goto sea_exit;
+	}
 
-	memset(rqst, 0, sizeof(rqst));
-	resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
-	memset(rsp_iov, 0, sizeof(rsp_iov));
+	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
+	if (!utf16_path) {
+		rc = -ENOMEM;
+		goto sea_exit;
+	}
 
 	if (ses->server->ops->query_all_EAs) {
 		if (!ea_value) {
@@ -1124,6 +1154,8 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
 				resp_buftype, rsp_iov);
 
  sea_exit:
+	if (cifs_sb->mnt_cifs_flags | CIFS_MOUNT_ENCODED_XATTR)
+		kfree(ea_name);
 	kfree(ea);
 	kfree(utf16_path);
 	SMB2_open_free(&rqst[0]);
-- 
2.20.1