| Message ID | 20171031180319.19258-11-bart.vanassche@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 10/31/2017 07:03 PM, Bart Van Assche wrote: > Certain behavior of the initiator can cause the target driver to > send both a reject and a SCSI response. If that happens two > target_put_sess_cmd() calls will occur without the command having > been removed from conn_cmd_list. In other words, conn_cmd_list > will get corrupted once the freed memory is reused. Although the > Linux kernel can detect list corruption if list debugging is > enabled, in this case the context in which list corruption is > detected is not related to the context that caused list corruption. > Hence add WARN_ON() statements that report the context that is > causing list corruption. > > Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> > Cc: Nicholas Bellinger <nab@linux-iscsi.org> > Cc: Christoph Hellwig <hch@lst.de> > Cc: Hannes Reinecke <hare@suse.com> > Cc: Mike Christie <mchristi@redhat.com> > --- > drivers/target/iscsi/iscsi_target_util.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c > index 1e36f83b5961..70c6b9bfc04e 100644 > --- a/drivers/target/iscsi/iscsi_target_util.c > +++ b/drivers/target/iscsi/iscsi_target_util.c > @@ -694,6 +694,8 @@ void iscsit_release_cmd(struct iscsi_cmd *cmd) > struct iscsi_session *sess; > struct se_cmd *se_cmd = &cmd->se_cmd; > > + WARN_ON(!list_empty(&cmd->i_conn_node)); > + > if (cmd->conn) > sess = cmd->conn->sess; > else > @@ -716,6 +718,8 @@ void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool check_queues) > { > struct iscsi_conn *conn = cmd->conn; > > + WARN_ON(!list_empty(&cmd->i_conn_node)); > + > if (cmd->data_direction == DMA_TO_DEVICE) { > iscsit_stop_dataout_timer(cmd); > iscsit_free_r2ts_from_list(cmd); > Well, I would rather fix the target code itself... But anyway: Reviewed-by: Hannes Reinecke <hare@suse.com> Cheers, Hannes
diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c index 1e36f83b5961..70c6b9bfc04e 100644 --- a/drivers/target/iscsi/iscsi_target_util.c +++ b/drivers/target/iscsi/iscsi_target_util.c @@ -694,6 +694,8 @@ void iscsit_release_cmd(struct iscsi_cmd *cmd) struct iscsi_session *sess; struct se_cmd *se_cmd = &cmd->se_cmd; + WARN_ON(!list_empty(&cmd->i_conn_node)); + if (cmd->conn) sess = cmd->conn->sess; else @@ -716,6 +718,8 @@ void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool check_queues) { struct iscsi_conn *conn = cmd->conn; + WARN_ON(!list_empty(&cmd->i_conn_node)); + if (cmd->data_direction == DMA_TO_DEVICE) { iscsit_stop_dataout_timer(cmd); iscsit_free_r2ts_from_list(cmd);
Certain behavior of the initiator can cause the target driver to send both a reject and a SCSI response. If that happens two target_put_sess_cmd() calls will occur without the command having been removed from conn_cmd_list. In other words, conn_cmd_list will get corrupted once the freed memory is reused. Although the Linux kernel can detect list corruption if list debugging is enabled, in this case the context in which list corruption is detected is not related to the context that caused list corruption. Hence add WARN_ON() statements that report the context that is causing list corruption. Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Cc: Nicholas Bellinger <nab@linux-iscsi.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Hannes Reinecke <hare@suse.com> Cc: Mike Christie <mchristi@redhat.com> --- drivers/target/iscsi/iscsi_target_util.c | 4 ++++ 1 file changed, 4 insertions(+)