Commit db9bfd64 authored Sep 03, 2014 by Mike Christie Committed by James Bottomley Sep 19, 2014

[SCSI] libiscsi: fix potential buffer overrun in __iscsi_conn_send_pdu

This patches fixes a potential buffer overrun in __iscsi_conn_send_pdu.
This function is used by iscsi drivers and userspace to send iscsi PDUs/
commands. For login commands, we have a set buffer size. For all other
commands we do not support data buffers.

This was reported by Dan Carpenter here:
http://www.spinics.net/lists/linux-scsi/msg66838.html



Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

parent f3b59331

drivers/scsi/libiscsi.c

+10 −0

Original line number	Diff line number	Diff line
		@@ -717,11 +717,21 @@ __iscsi_conn_send_pdu(struct iscsi_conn conn, struct iscsi_hdr hdr,
		return NULL;
		}

		if (data_size > ISCSI_DEF_MAX_RECV_SEG_LEN) {
		iscsi_conn_printk(KERN_ERR, conn, "Invalid buffer len of %u for login task. Max len is %u\n", data_size, ISCSI_DEF_MAX_RECV_SEG_LEN);
		return NULL;
		}

		task = conn->login_task;
		} else {
		if (session->state != ISCSI_STATE_LOGGED_IN)
		return NULL;

		if (data_size != 0) {
		iscsi_conn_printk(KERN_ERR, conn, "Can not send data buffer of len %u for op 0x%x\n", data_size, opcode);
		return NULL;
		}

		BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
		BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);