[PATCH 4.14 008/126] SMB3: Backup intent flag missing for directory opens with backupuid mounts

From: Greg Kroah-Hartman
Date: Mon Sep 17 2018 - 19:00:24 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Steve French <stfrench@xxxxxxxxxxxxx>

commit 5e19697b56a64004e2d0ff1bb952ea05493c088f upstream.

When "backup intent" is requested on the mount (e.g. backupuid or
backupgid mount options), the corresponding flag needs to be set
on opens of directories (and files) but was missing in some
places causing access denied trying to enumerate and backup
servers.

Fixes kernel bugzilla #200953
https://bugzilla.kernel.org/show_bug.cgi?id=200953

Reported-and-tested-by: <whh@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
CC: Stable <stable@xxxxxxxxxxxxxxx>
Reviewed-by: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/cifs/inode.c | 2 ++
fs/cifs/smb2ops.c | 25 ++++++++++++++++++++-----
2 files changed, 22 insertions(+), 5 deletions(-)

--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -467,6 +467,8 @@ cifs_sfu_type(struct cifs_fattr *fattr,
oparms.cifs_sb = cifs_sb;
oparms.desired_access = GENERIC_READ;
oparms.create_options = CREATE_NOT_DIR;
+ if (backup_cred(cifs_sb))
+ oparms.create_options |= CREATE_OPEN_BACKUP_INTENT;
oparms.disposition = FILE_OPEN;
oparms.path = path;
oparms.fid = &fid;
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -385,7 +385,10 @@ smb2_is_path_accessible(const unsigned i
oparms.tcon = tcon;
oparms.desired_access = FILE_READ_ATTRIBUTES;
oparms.disposition = FILE_OPEN;
- oparms.create_options = 0;
+ if (backup_cred(cifs_sb))
+ oparms.create_options = CREATE_OPEN_BACKUP_INTENT;
+ else
+ oparms.create_options = 0;
oparms.fid = &fid;
oparms.reconnect = false;

@@ -534,7 +537,10 @@ smb2_query_eas(const unsigned int xid, s
oparms.tcon = tcon;
oparms.desired_access = FILE_READ_EA;
oparms.disposition = FILE_OPEN;
- oparms.create_options = 0;
+ if (backup_cred(cifs_sb))
+ oparms.create_options = CREATE_OPEN_BACKUP_INTENT;
+ else
+ oparms.create_options = 0;
oparms.fid = &fid;
oparms.reconnect = false;

@@ -613,7 +619,10 @@ smb2_set_ea(const unsigned int xid, stru
oparms.tcon = tcon;
oparms.desired_access = FILE_WRITE_EA;
oparms.disposition = FILE_OPEN;
- oparms.create_options = 0;
+ if (backup_cred(cifs_sb))
+ oparms.create_options = CREATE_OPEN_BACKUP_INTENT;
+ else
+ oparms.create_options = 0;
oparms.fid = &fid;
oparms.reconnect = false;

@@ -1215,7 +1224,10 @@ smb2_query_dir_first(const unsigned int
oparms.tcon = tcon;
oparms.desired_access = FILE_READ_ATTRIBUTES | FILE_READ_DATA;
oparms.disposition = FILE_OPEN;
- oparms.create_options = 0;
+ if (backup_cred(cifs_sb))
+ oparms.create_options = CREATE_OPEN_BACKUP_INTENT;
+ else
+ oparms.create_options = 0;
oparms.fid = fid;
oparms.reconnect = false;

@@ -1491,7 +1503,10 @@ smb2_query_symlink(const unsigned int xi
oparms.tcon = tcon;
oparms.desired_access = FILE_READ_ATTRIBUTES;
oparms.disposition = FILE_OPEN;
- oparms.create_options = 0;
+ if (backup_cred(cifs_sb))
+ oparms.create_options = CREATE_OPEN_BACKUP_INTENT;
+ else
+ oparms.create_options = 0;
oparms.fid = &fid;
oparms.reconnect = false;