From db9bfd64b14a3a8f1868d2164518fdeab1b26ad1 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Wed, 3 Sep 2014 00:00:39 -0500 Subject: [PATCH] [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 Signed-off-by: Mike Christie Reviewed-by: Sagi Grimberg Signed-off-by: Christoph Hellwig Cc: stable@vger.kernel.org Signed-off-by: James Bottomley --- drivers/scsi/libiscsi.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index ea025e4806b6..191b59793519 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -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); -- 2.20.1