Commit e98ecc6e authored by Zhang Xiaoxu's avatar Zhang Xiaoxu Committed by Steve French
Browse files

cifs: Fix the error length of VALIDATE_NEGOTIATE_INFO message 



Commit d5c7076b ("smb3: add smb3.1.1 to default dialect list")
extend the dialects from 3 to 4, but forget to decrease the extended
length when specific the dialect, then the message length is larger
than expected.

This maybe leak some info through network because not initialize the
message body.

After apply this patch, the VALIDATE_NEGOTIATE_INFO message length is
reduced from 28 bytes to 26 bytes.

Fixes: d5c7076b ("smb3: add smb3.1.1 to default dialect list")
Signed-off-by: default avatarZhang Xiaoxu <zhangxiaoxu5@huawei.com>
Cc: <stable@vger.kernel.org>
Acked-by: default avatarPaulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: default avatarTom Talpey <tom@talpey.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent bb44c31c

fs/cifs/smb2pdu.c

+2 −2
Original line number Diff line number Diff line
@@ -1169,9 +1169,9 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon) 
		pneg_inbuf->Dialects[0] =

			cpu_to_le16(server->vals->protocol_id);

		pneg_inbuf->DialectCount = cpu_to_le16(1);

		/* structure is big enough for 3 dialects, sending only 1 */

		/* structure is big enough for 4 dialects, sending only 1 */

		inbuflen = sizeof(*pneg_inbuf) -

				sizeof(pneg_inbuf->Dialects[0]) * 2;

				sizeof(pneg_inbuf->Dialects[0]) * 3;

	}



	rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID,