[PATCH 5.4 029/110] cifs: set correct max-buffer-size for smb2_ioctl_init()

Greg Kroah-Hartman
2020-01-30T18:43:08Z

From: Ronnie Sahlberg <lsahlber@redhat.com>

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@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1461,7 +1461,9 @@ 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 */
@@ -2634,7 +2636,10 @@ 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;