Commit a2d9daad authored Oct 20, 2017 by David Disseldorp Committed by Steve French Oct 25, 2017

SMB: fix validate negotiate info uninitialised memory use

An undersize validate negotiate info server response causes the client
to use uninitialised memory for struct validate_negotiate_info_rsp
comparisons of Dialect, SecurityMode and/or Capabilities members.

Link: https://bugzilla.samba.org/show_bug.cgi?id=13092


Fixes: 7db0a6ef ("SMB3: Work around mount failure when using SMB3 dialect to Macs")
Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>

parent fe83bebc

fs/cifs/smb2pdu.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -727,7 +727,8 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
		rsplen);

		/* relax check since Mac returns max bufsize allowed on ioctl */
		if (rsplen > CIFSMaxBufSize)
		if ((rsplen > CIFSMaxBufSize)
		\|\| (rsplen < sizeof(struct validate_negotiate_info_rsp)))
		goto err_rsp_free;
		}