[PATCH 5.5 30/56] cifs: set correct max-buffer-size for smb2_ioctl_init()

[Greg Kroah-Hartman]

From: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>

commit 731b82bb1750a906c1e7f070aedf5505995ebea7 upstream.

Fix two places where we need to adjust down the max response size for
ioctl when it is used together with compounding.

Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Reviewed-by: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
CC: Stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 fs/cifs/smb2ops.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1523,7 +1523,9 @@ smb2_ioctl_query_info(const unsigned int
 					     COMPOUND_FID, COMPOUND_FID,
 					     qi.info_type, true, buffer,
 					     qi.output_buffer_length,
-					     CIFSMaxBufSize);
+					     CIFSMaxBufSize -
+					     MAX_SMB2_CREATE_RESPONSE_SIZE -
+					     MAX_SMB2_CLOSE_RESPONSE_SIZE);
 		}
 	} else if (qi.flags == PASSTHRU_SET_INFO) {
 		/* Can eventually relax perm check since server enforces too */
@@ -2697,7 +2699,10 @@ smb2_query_symlink(const unsigned int xi
 
 	rc = SMB2_ioctl_init(tcon, &rqst[1], fid.persistent_fid,
 			     fid.volatile_fid, FSCTL_GET_REPARSE_POINT,
-			     true /* is_fctl */, NULL, 0, CIFSMaxBufSize);
+			     true /* is_fctl */, NULL, 0,
+			     CIFSMaxBufSize -
+			     MAX_SMB2_CREATE_RESPONSE_SIZE -
+			     MAX_SMB2_CLOSE_RESPONSE_SIZE);
 	if (rc)
 		goto querty_exit;