From db9bfd64b14a3a8f1868d2164518fdeab1b26ad1 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Wed, 3 Sep 2014 00:00:39 -0500 Subject: [PATCH 1/3] [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); From e8be1cf58d5b4ddbf8089700df8458f432ed5934 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 12 Sep 2014 16:00:32 -0700 Subject: [PATCH 2/3] [SCSI] fix regression that accidentally disabled block-based tcq The scsi blk-mq support accidentally flipped a conditional, which lead to never enabling block based tcq when using the legacy request path. Fixes: d285203cf647d7c9 scsi: add support for a blk-mq based I/O path. Reported-by: Hans de Goede Signed-off-by: Christoph Hellwig Signed-off-by: James Bottomley --- include/scsi/scsi_tcq.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/scsi/scsi_tcq.h b/include/scsi/scsi_tcq.h index cdcc90b07ecb..e64583560701 100644 --- a/include/scsi/scsi_tcq.h +++ b/include/scsi/scsi_tcq.h @@ -68,7 +68,7 @@ static inline void scsi_activate_tcq(struct scsi_device *sdev, int depth) return; if (!shost_use_blk_mq(sdev->host) && - blk_queue_tagged(sdev->request_queue)) + !blk_queue_tagged(sdev->request_queue)) blk_queue_init_tags(sdev->request_queue, depth, sdev->host->bqt); From f81426a84bef870d26e5e752772d8ca203cd4aed Mon Sep 17 00:00:00 2001 From: Daniel Gryniewicz Date: Tue, 16 Sep 2014 10:41:13 -0400 Subject: [PATCH 3/3] [SCSI] fix for bidi use after free When ending a bi-directionional SCSI request, blk_finish_request() cleans up and frees the request, but scsi_release_bidi_buffers() tries to indirect through the request to find it's data buffers. This causes a panic due to a null pointer dereference. Move the call to scsi_release_bidi_buffers() before the call to blk_finish_request(). Signed-off-by: Daniel Gryniewicz Reviewed-by: Webb Scales Signed-off-by: Christoph Hellwig Signed-off-by: James Bottomley --- drivers/scsi/scsi_lib.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index d837dc180522..aaea4b98af16 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -733,12 +733,13 @@ static bool scsi_end_request(struct request *req, int error, } else { unsigned long flags; + if (bidi_bytes) + scsi_release_bidi_buffers(cmd); + spin_lock_irqsave(q->queue_lock, flags); blk_finish_request(req, error); spin_unlock_irqrestore(q->queue_lock, flags); - if (bidi_bytes) - scsi_release_bidi_buffers(cmd); scsi_release_buffers(cmd); scsi_next_command(cmd); }