From: Colin Ian King <[email protected]>
Currently pointer tdata is being dereferenced on the initialization of
pointer skb before tdata is null checked. This could lead to a potential
null pointer dereference. Fix this by dereferencing tdata after tdata
has been null pointer sanity checked.
Addresses-Coverity: ("Dereference before null check")
Fixes: e33c2482289b ("scsi: cxgb4i: Add support for iSCSI segmentation offload")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/scsi/cxgbi/libcxgbi.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/scsi/cxgbi/libcxgbi.c b/drivers/scsi/cxgbi/libcxgbi.c
index 1fb101c616b7..a6119d9daedf 100644
--- a/drivers/scsi/cxgbi/libcxgbi.c
+++ b/drivers/scsi/cxgbi/libcxgbi.c
@@ -2147,7 +2147,7 @@ int cxgbi_conn_init_pdu(struct iscsi_task *task, unsigned int offset,
struct iscsi_conn *conn = task->conn;
struct iscsi_tcp_task *tcp_task = task->dd_data;
struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
- struct sk_buff *skb = tdata->skb;
+ struct sk_buff *skb;
struct scsi_cmnd *sc = task->sc;
u32 expected_count, expected_offset;
u32 datalen = count, dlimit = 0;
@@ -2161,6 +2161,7 @@ int cxgbi_conn_init_pdu(struct iscsi_task *task, unsigned int offset,
tcp_task ? tcp_task->dd_data : NULL, tdata);
return -EINVAL;
}
+ skb = tdata->skb;
log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
"task 0x%p,0x%p, skb 0x%p, 0x%x,0x%x,0x%x, %u+%u.\n",
@@ -2365,7 +2366,7 @@ int cxgbi_conn_xmit_pdu(struct iscsi_task *task)
struct iscsi_tcp_task *tcp_task = task->dd_data;
struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
struct cxgbi_task_tag_info *ttinfo = &tdata->ttinfo;
- struct sk_buff *skb = tdata->skb;
+ struct sk_buff *skb;
struct cxgbi_sock *csk = NULL;
u32 pdulen = 0;
u32 datalen;
@@ -2378,6 +2379,7 @@ int cxgbi_conn_xmit_pdu(struct iscsi_task *task)
return -EINVAL;
}
+ skb = tdata->skb;
if (!skb) {
log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
"task 0x%p, skb NULL.\n", task);
--
2.27.0
On Thu, Jul 09, 2020 at 02:52:17PM +0100, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> Currently pointer tdata is being dereferenced on the initialization of
> pointer skb before tdata is null checked. This could lead to a potential
> null pointer dereference. Fix this by dereferencing tdata after tdata
> has been null pointer sanity checked.
>
> Addresses-Coverity: ("Dereference before null check")
> Fixes: e33c2482289b ("scsi: cxgb4i: Add support for iSCSI segmentation offload")
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/scsi/cxgbi/libcxgbi.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/scsi/cxgbi/libcxgbi.c b/drivers/scsi/cxgbi/libcxgbi.c
> index 1fb101c616b7..a6119d9daedf 100644
> --- a/drivers/scsi/cxgbi/libcxgbi.c
> +++ b/drivers/scsi/cxgbi/libcxgbi.c
> @@ -2147,7 +2147,7 @@ int cxgbi_conn_init_pdu(struct iscsi_task *task, unsigned int offset,
> struct iscsi_conn *conn = task->conn;
> struct iscsi_tcp_task *tcp_task = task->dd_data;
> struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
> - struct sk_buff *skb = tdata->skb;
> + struct sk_buff *skb;
> struct scsi_cmnd *sc = task->sc;
> u32 expected_count, expected_offset;
> u32 datalen = count, dlimit = 0;
> @@ -2161,6 +2161,7 @@ int cxgbi_conn_init_pdu(struct iscsi_task *task, unsigned int offset,
> tcp_task ? tcp_task->dd_data : NULL, tdata);
> return -EINVAL;
> }
> + skb = tdata->skb;
>
> log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
> "task 0x%p,0x%p, skb 0x%p, 0x%x,0x%x,0x%x, %u+%u.\n",
> @@ -2365,7 +2366,7 @@ int cxgbi_conn_xmit_pdu(struct iscsi_task *task)
> struct iscsi_tcp_task *tcp_task = task->dd_data;
> struct cxgbi_task_data *tdata = iscsi_task_cxgbi_data(task);
> struct cxgbi_task_tag_info *ttinfo = &tdata->ttinfo;
> - struct sk_buff *skb = tdata->skb;
> + struct sk_buff *skb;
> struct cxgbi_sock *csk = NULL;
> u32 pdulen = 0;
> u32 datalen;
> @@ -2378,6 +2379,7 @@ int cxgbi_conn_xmit_pdu(struct iscsi_task *task)
> return -EINVAL;
> }
>
> + skb = tdata->skb;
> if (!skb) {
> log_debug(1 << CXGBI_DBG_ISCSI | 1 << CXGBI_DBG_PDU_TX,
> "task 0x%p, skb NULL.\n", task);
Acked-by: Varun Prakash <[email protected]>
On Thu, 9 Jul 2020 14:52:17 +0100, Colin King wrote:
> Currently pointer tdata is being dereferenced on the initialization of
> pointer skb before tdata is null checked. This could lead to a potential
> null pointer dereference. Fix this by dereferencing tdata after tdata
> has been null pointer sanity checked.
Applied to 5.9/scsi-queue, thanks!
[1/1] scsi: cxgb4i: Fix dereference of pointer tdata before it is null checked
https://git.kernel.org/mkp/scsi/c/b92a4a9f7be8
--
Martin K. Petersen Oracle Linux Engineering