on non-posix shares, clear write bits in mode when ATTR_READONLY is set

When mounting a share with posix extensions disabled,
cifs_get_inode_info turns off all the write bits in the mode for regular
files if ATTR_READONLY is set. Directories and other inode types,
however, can also have ATTR_READONLY set, but the mode gives no
indication of this.

This patch makes this apply to other inode types besides regular files.
It also cleans up how modes are set in cifs_get_inode_info for both the
"normal" and "dynperm" cases.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 36 insertions, 40 deletions

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 129dbfe4dca7..ae5bcaf2031c 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -418,6 +418,7 @@ int cifs_get_inode_info(struct inode **pinode,
         char *buf = NULL;
         bool adjustTZ = false;
         bool is_dfs_referral = false;
+        umode_t default_mode;
 
         pTcon = cifs_sb->tcon;
         cFYI(1, ("Getting info on %s", full_path));
@@ -530,47 +531,42 @@ int cifs_get_inode_info(struct inode **pinode,
                 inode->i_mtime.tv_sec += pTcon->ses->server->timeAdj;
         }
 
-        /* set default mode. will override for dirs below */
-        if (atomic_read(&cifsInfo->inUse) == 0)
-                /* new inode, can safely set these fields */
-                inode->i_mode = cifs_sb->mnt_file_mode;
-        else /* since we set the inode type below we need to mask off
-             to avoid strange results if type changes and both
-             get orred in */
-                inode->i_mode &= ~S_IFMT;
-/*      if (attr & ATTR_REPARSE)  */
-        /* We no longer handle these as symlinks because we could not
-           follow them due to the absolute path with drive letter */
-        if (attr & ATTR_DIRECTORY) {
-        /* override default perms since we do not do byte range locking
-           on dirs */
-                inode->i_mode = cifs_sb->mnt_dir_mode;
-                inode->i_mode |= S_IFDIR;
-        } else if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) &&
-                   (cifsInfo->cifsAttrs & ATTR_SYSTEM) &&
-                   /* No need to le64 convert size of zero */
-                   (pfindData->EndOfFile == 0)) {
-                inode->i_mode = cifs_sb->mnt_file_mode;
-                inode->i_mode |= S_IFIFO;
-/* BB Finish for SFU style symlinks and devices */
-        } else if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) &&
-                   (cifsInfo->cifsAttrs & ATTR_SYSTEM)) {
-                if (decode_sfu_inode(inode, le64_to_cpu(pfindData->EndOfFile),
-                                     full_path, cifs_sb, xid))
-                        cFYI(1, ("Unrecognized sfu inode type"));
-
-                cFYI(1, ("sfu mode 0%o", inode->i_mode));
+        /* get default inode mode */
+        if (attr & ATTR_DIRECTORY)
+                default_mode = cifs_sb->mnt_dir_mode;
+        else
+                default_mode = cifs_sb->mnt_file_mode;
+
+        /* set permission bits */
+        if (atomic_read(&cifsInfo->inUse) == 0 ||
+            (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM) == 0)
+                inode->i_mode = default_mode;
+        else {
+                /* just reenable write bits if !ATTR_READONLY */
+                if ((inode->i_mode & S_IWUGO) == 0 &&
+                    (attr & ATTR_READONLY) == 0)
+                        inode->i_mode |= (S_IWUGO & default_mode);
+                        inode->i_mode &= ~S_IFMT;
+        }
+        /* clear write bits if ATTR_READONLY is set */
+        if (attr & ATTR_READONLY)
+                inode->i_mode &= ~S_IWUGO;
+
+        /* set inode type */
+        if ((attr & ATTR_SYSTEM) &&
+            (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL)) {
+                /* no need to fix endianness on 0 */
+                if (pfindData->EndOfFile == 0)
+                        inode->i_mode |= S_IFIFO;
+                else if (decode_sfu_inode(inode,
+                                le64_to_cpu(pfindData->EndOfFile),
+                                full_path, cifs_sb, xid))
+                        cFYI(1, ("unknown SFU file type\n"));
         } else {
-                inode->i_mode |= S_IFREG;
-                /* treat dos attribute of read-only as read-only mode eg 555 */
-                if (cifsInfo->cifsAttrs & ATTR_READONLY)
-                        inode->i_mode &= ~(S_IWUGO);
-                else if ((inode->i_mode & S_IWUGO) == 0)
-                        /* the ATTR_READONLY flag may have been */
-                        /* changed on server -- set any w bits  */
-                        /* allowed by mnt_file_mode             */
-                        inode->i_mode |= (S_IWUGO & cifs_sb->mnt_file_mode);
-        /* BB add code to validate if device or weird share or device type? */
+                if (attr & ATTR_DIRECTORY)
+                        inode->i_mode |= S_IFDIR;
+                else
+                        inode->i_mode |= S_IFREG;
         }
 
         spin_lock(&inode->i_lock);