smb3: add support for stat of WSL reparse points for special file types
This is needed so when mounting to Windows we do not
misinterpret various special files created by Linux (WSL) as symlinks.
An earlier patch addressed readdir. This patch fixes stat (getattr).
With this patch:
File: /mnt1/char
Size: 0 Blocks: 0 IO Block: 16384 character special file
Device: 34h/52d Inode: 844424930132069 Links: 1 Device type: 0,0
Access: (0755/crwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2020-10-21 17:46:51.839458900 -0500
Modify: 2020-10-21 17:46:51.839458900 -0500
Change: 2020-10-21 18:30:39.797358800 -0500
Birth: -
File: /mnt1/fifo
Size: 0 Blocks: 0 IO Block: 16384 fifo
Device: 34h/52d Inode: 1125899906842722 Links: 1
Access: (0755/prwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2020-10-21 16:21:37.259249700 -0500
Modify: 2020-10-21 16:21:37.259249700 -0500
Change: 2020-10-21 18:30:39.797358800 -0500
Birth: -
File: /mnt1/block
Size: 0 Blocks: 0 IO Block: 16384 block special file
Device: 34h/52d Inode: 844424930132068 Links: 1 Device type: 0,0
Access: (0755/brwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2020-10-21 17:10:47.913103200 -0500
Modify: 2020-10-21 17:10:47.913103200 -0500
Change: 2020-10-21 18:30:39.796725500 -0500
Birth: -
without the patch all show up incorrectly as symlinks with annoying "operation not supported error also returned"
File: /mnt1/charstat: cannot read symbolic link '/mnt1/char': Operation not supported
Size: 0 Blocks: 0 IO Block: 16384 symbolic link
Device: 34h/52d Inode: 844424930132069 Links: 1
Access: (0000/l---------) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2020-10-21 17:46:51.839458900 -0500
Modify: 2020-10-21 17:46:51.839458900 -0500
Change: 2020-10-21 18:30:39.797358800 -0500
Birth: -
File: /mnt1/fifostat: cannot read symbolic link '/mnt1/fifo': Operation not supported
Size: 0 Blocks: 0 IO Block: 16384 symbolic link
Device: 34h/52d Inode: 1125899906842722 Links: 1
Access: (0000/l---------) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2020-10-21 16:21:37.259249700 -0500
Modify: 2020-10-21 16:21:37.259249700 -0500
Change: 2020-10-21 18:30:39.797358800 -0500
Birth: -
File: /mnt1/blockstat: cannot read symbolic link '/mnt1/block': Operation not supported
Size: 0 Blocks: 0 IO Block: 16384 symbolic link
Device: 34h/52d Inode: 844424930132068 Links: 1
Access: (0000/l---------) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2020-10-21 17:10:47.913103200 -0500
Modify: 2020-10-21 17:10:47.913103200 -0500
Change: 2020-10-21 18:30:39.796725500 -0500
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index daec31b..9ee5f30 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -656,7 +656,7 @@ smb311_posix_info_to_fattr(struct cifs_fattr *fattr, struct smb311_posix_qinfo *
static void
cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info,
struct super_block *sb, bool adjust_tz,
- bool symlink)
+ bool symlink, u32 reparse_tag)
{
struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
@@ -684,8 +684,22 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info,
fattr->cf_createtime = le64_to_cpu(info->CreationTime);
fattr->cf_nlink = le32_to_cpu(info->NumberOfLinks);
-
- if (symlink) {
+ if (reparse_tag == IO_REPARSE_TAG_LX_SYMLINK) {
+ fattr->cf_mode |= S_IFLNK | cifs_sb->mnt_file_mode;
+ fattr->cf_dtype = DT_LNK;
+ } else if (reparse_tag == IO_REPARSE_TAG_LX_FIFO) {
+ fattr->cf_mode |= S_IFIFO | cifs_sb->mnt_file_mode;
+ fattr->cf_dtype = DT_FIFO;
+ } else if (reparse_tag == IO_REPARSE_TAG_AF_UNIX) {
+ fattr->cf_mode |= S_IFSOCK | cifs_sb->mnt_file_mode;
+ fattr->cf_dtype = DT_SOCK;
+ } else if (reparse_tag == IO_REPARSE_TAG_LX_CHR) {
+ fattr->cf_mode |= S_IFCHR | cifs_sb->mnt_file_mode;
+ fattr->cf_dtype = DT_CHR;
+ } else if (reparse_tag == IO_REPARSE_TAG_LX_BLK) {
+ fattr->cf_mode |= S_IFBLK | cifs_sb->mnt_file_mode;
+ fattr->cf_dtype = DT_BLK;
+ } else if (symlink) { /* TODO add more reparse tag checks */
fattr->cf_mode = S_IFLNK;
fattr->cf_dtype = DT_LNK;
} else if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
@@ -740,8 +754,9 @@ cifs_get_file_info(struct file *filp)
rc = server->ops->query_file_info(xid, tcon, &cfile->fid, &find_data);
switch (rc) {
case 0:
+ /* TODO: add support to query reparse tag */
cifs_all_info_to_fattr(&fattr, &find_data, inode->i_sb, false,
- false);
+ false, 0 /* no reparse tag */);
break;
case -EREMOTE:
cifs_create_dfs_fattr(&fattr, inode->i_sb);
@@ -910,12 +925,13 @@ cifs_get_inode_info(struct inode **inode,
struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
bool adjust_tz = false;
struct cifs_fattr fattr = {0};
- bool symlink = false;
+ bool is_reparse_point = false;
FILE_ALL_INFO *data = in_data;
FILE_ALL_INFO *tmp_data = NULL;
void *smb1_backup_rsp_buf = NULL;
int rc = 0;
int tmprc = 0;
+ __u32 reparse_tag = 0;
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink))
@@ -938,8 +954,8 @@ cifs_get_inode_info(struct inode **inode,
goto out;
}
rc = server->ops->query_path_info(xid, tcon, cifs_sb,
- full_path, tmp_data,
- &adjust_tz, &symlink);
+ full_path, tmp_data,
+ &adjust_tz, &is_reparse_point);
data = tmp_data;
}
@@ -949,7 +965,19 @@ cifs_get_inode_info(struct inode **inode,
switch (rc) {
case 0:
- cifs_all_info_to_fattr(&fattr, data, sb, adjust_tz, symlink);
+ /*
+ * If the file is a reparse point, it is more complicated
+ * since we have to check if its reparse tag matches a known
+ * special file type e.g. symlink or fifo or char etc.
+ */
+ if ((le32_to_cpu(data->Attributes) & ATTR_REPARSE) &&
+ server->ops->query_reparse_tag) {
+ rc = server->ops->query_reparse_tag(xid, tcon, cifs_sb,
+ full_path, &reparse_tag);
+ cifs_dbg(FYI, "reparse tag 0x%x\n", reparse_tag);
+ }
+ cifs_all_info_to_fattr(&fattr, data, sb, adjust_tz,
+ is_reparse_point, reparse_tag);
break;
case -EREMOTE:
/* DFS link, no metadata available on this server */
