Major and minor numbers for char and block devices are mandatory for stat.
So check that the WSL EA $LXDEV is present for WSL CHR and BLK reparse
points.
WSL reparse point tag determinate type of the file. But file type is
present also in the WSL EA $LXMOD. So check that both file types are same.
Fixes: 78e26bec4d6d ("smb: client: parse uid, gid, mode and dev from WSL reparse points")
Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
---
fs/smb/client/reparse.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
diff --git a/fs/smb/client/reparse.c b/fs/smb/client/reparse.c
index 9fe9dd71a6fa..9e40f5709c7f 100644
--- a/fs/smb/client/reparse.c
+++ b/fs/smb/client/reparse.c
@@ -1105,11 +1105,12 @@ struct reparse_data_buffer *smb2_get_reparse_point_buffer(const struct kvec *rsp
le32_to_cpu(io->OutputOffset));
}
-static void wsl_to_fattr(struct cifs_open_info_data *data,
+static bool wsl_to_fattr(struct cifs_open_info_data *data,
struct cifs_sb_info *cifs_sb,
u32 tag, struct cifs_fattr *fattr)
{
struct smb2_file_full_ea_info *ea;
+ bool have_xattr_dev = false;
u32 next = 0;
switch (tag) {
@@ -1152,13 +1153,24 @@ static void wsl_to_fattr(struct cifs_open_info_data *data,
fattr->cf_uid = wsl_make_kuid(cifs_sb, v);
else if (!strncmp(name, SMB2_WSL_XATTR_GID, nlen))
fattr->cf_gid = wsl_make_kgid(cifs_sb, v);
- else if (!strncmp(name, SMB2_WSL_XATTR_MODE, nlen))
+ else if (!strncmp(name, SMB2_WSL_XATTR_MODE, nlen)) {
+ /* File type in reparse point tag and in xattr mode must match. */
+ if (S_DT(fattr->cf_mode) != S_DT(le32_to_cpu(*(__le32 *)v)))
+ return false;
fattr->cf_mode = (umode_t)le32_to_cpu(*(__le32 *)v);
- else if (!strncmp(name, SMB2_WSL_XATTR_DEV, nlen))
+ } else if (!strncmp(name, SMB2_WSL_XATTR_DEV, nlen)) {
fattr->cf_rdev = reparse_mkdev(v);
+ have_xattr_dev = true;
+ }
} while (next);
out:
+
+ /* Major and minor numbers for char and block devices are mandatory. */
+ if (!have_xattr_dev && (tag == IO_REPARSE_TAG_LX_CHR || tag == IO_REPARSE_TAG_LX_BLK))
+ return false;
+
fattr->cf_dtype = S_DT(fattr->cf_mode);
+ return true;
}
static bool posix_reparse_to_fattr(struct cifs_sb_info *cifs_sb,
@@ -1221,7 +1233,9 @@ bool cifs_reparse_point_to_fattr(struct cifs_sb_info *cifs_sb,
case IO_REPARSE_TAG_AF_UNIX:
case IO_REPARSE_TAG_LX_CHR:
case IO_REPARSE_TAG_LX_BLK:
- wsl_to_fattr(data, cifs_sb, tag, fattr);
+ ok = wsl_to_fattr(data, cifs_sb, tag, fattr);
+ if (!ok)
+ return false;
break;
case IO_REPARSE_TAG_NFS:
ok = posix_reparse_to_fattr(cifs_sb, fattr, data);
--
2.20.1
