scsi: qla2xxx: Fix double scsi_done for abort path

[ Upstream commit f45bca8c5052e8c59bab64ee90c44441678b9a52 ]

Current code assumes abort will remove the original command from the active
list where scsi_done will not be called. Instead, the eh_abort thread will
do the scsi_done. That is not the case.  Instead, we have a double
scsi_done calls triggering use after free.

Abort will tell FW to release the command from FW possesion. The original
command will return to ULP with error in its normal fashion via scsi_done.
eh_abort path would wait for the original command completion before
returning.  eh_abort path will not perform the scsi_done call.

Fixes: 219d27d7147e0 ("scsi: qla2xxx: Fix race conditions in the code for aborting SCSI commands")
Cc: stable@vger.kernel.org # 5.2
Link: https://lore.kernel.org/r/20191105150657.8092-6-hmadhani@marvell.com
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Arun Easi <aeasi@marvell.com>
Signed-off-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index ea1728fe2c7686e3e4a419f4d6ea725cf9160e5b..29af738ca203e700e1e38b4d841785a6d25e8c58 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -531,13 +531,16 @@ typedef struct srb {
         */
        uint8_t cmd_type;
        uint8_t pad[3];
-       atomic_t ref_count;
        struct kref cmd_kref;   /* need to migrate ref_count over to this */
        void *priv;
        wait_queue_head_t nvme_ls_waitq;
        struct fc_port *fcport;
        struct scsi_qla_host *vha;
        unsigned int start_timer:1;
+       unsigned int abort:1;
+       unsigned int aborted:1;
+       unsigned int completed:1;
+
        uint32_t handle;
        uint16_t flags;
        uint16_t type;

diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
index f7458d74ae3d2fcd632aaeffc1522fb66e38a156..9e32a90d4d7734bdb4e16168c93b09c1e088103a 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_isr.c
+++ b/drivers/scsi/qla2xxx/qla_isr.c
@@ -2473,6 +2473,11 @@ qla2x00_status_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, void *pkt)
                return;
        }
 
+       if (sp->abort)
+               sp->aborted = 1;
+       else
+               sp->completed = 1;
+
        if (sp->cmd_type != TYPE_SRB) {
                req->outstanding_cmds[handle] = NULL;
                ql_dbg(ql_dbg_io, vha, 0x3015,

diff --git a/drivers/scsi/qla2xxx/qla_nvme.c b/drivers/scsi/qla2xxx/qla_nvme.c
index 963094b3c30078f4761169a657928ccbeeb8285a..672da9b838e5209853d5cc7e10a8cf3ab8eb425f 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_nvme.c
+++ b/drivers/scsi/qla2xxx/qla_nvme.c
@@ -227,8 +227,8 @@ static void qla_nvme_abort_work(struct work_struct *work)
 
        if (ha->flags.host_shutting_down) {
                ql_log(ql_log_info, sp->fcport->vha, 0xffff,
-                   "%s Calling done on sp: %p, type: 0x%x, sp->ref_count: 0x%x\n",
-                   __func__, sp, sp->type, atomic_read(&sp->ref_count));
+                   "%s Calling done on sp: %p, type: 0x%x\n",
+                   __func__, sp, sp->type);
                sp->done(sp, 0);
                goto out;
        }

diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 3aa2dd43945bfb255dedbd614ab8fa5fe67ef063..ac2977bdc359502cbfa96581c5617d0f05b4d01d 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -716,11 +716,6 @@ qla2x00_sp_compl(void *ptr, int res)
        struct scsi_cmnd *cmd = GET_CMD_SP(sp);
        struct completion *comp = sp->comp;
 
-       if (WARN_ON_ONCE(atomic_read(&sp->ref_count) == 0))
-               return;
-
-       atomic_dec(&sp->ref_count);
-
        sp->free(sp);
        cmd->result = res;
        CMD_SP(cmd) = NULL;
@@ -820,11 +815,6 @@ qla2xxx_qpair_sp_compl(void *ptr, int res)
        struct scsi_cmnd *cmd = GET_CMD_SP(sp);
        struct completion *comp = sp->comp;
 
-       if (WARN_ON_ONCE(atomic_read(&sp->ref_count) == 0))
-               return;
-
-       atomic_dec(&sp->ref_count);
-
        sp->free(sp);
        cmd->result = res;
        CMD_SP(cmd) = NULL;
@@ -928,7 +918,7 @@ qla2xxx_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 
        sp->u.scmd.cmd = cmd;
        sp->type = SRB_SCSI_CMD;
-       atomic_set(&sp->ref_count, 1);
+
        CMD_SP(cmd) = (void *)sp;
        sp->free = qla2x00_sp_free_dma;
        sp->done = qla2x00_sp_compl;
@@ -1010,11 +1000,9 @@ qla2xxx_mqueuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd,
 
        sp->u.scmd.cmd = cmd;
        sp->type = SRB_SCSI_CMD;
-       atomic_set(&sp->ref_count, 1);
        CMD_SP(cmd) = (void *)sp;
        sp->free = qla2xxx_qpair_sp_free_dma;
        sp->done = qla2xxx_qpair_sp_compl;
-       sp->qpair = qpair;
 
        rval = ha->isp_ops->start_scsi_mq(sp);
        if (rval != QLA_SUCCESS) {
@@ -1207,16 +1195,6 @@ qla2x00_wait_for_chip_reset(scsi_qla_host_t *vha)
        return return_status;
 }
 
-static int
-sp_get(struct srb *sp)
-{
-       if (!refcount_inc_not_zero((refcount_t *)&sp->ref_count))
-               /* kref get fail */
-               return ENXIO;
-       else
-               return 0;
-}
-
 #define ISP_REG_DISCONNECT 0xffffffffU
 /**************************************************************************
 * qla2x00_isp_reg_stat
@@ -1272,6 +1250,9 @@ qla2xxx_eh_abort(struct scsi_cmnd *cmd)
        uint64_t lun;
        int rval;
        struct qla_hw_data *ha = vha->hw;
+       uint32_t ratov_j;
+       struct qla_qpair *qpair;
+       unsigned long flags;
 
        if (qla2x00_isp_reg_stat(ha)) {
                ql_log(ql_log_info, vha, 0x8042,
@@ -1284,11 +1265,27 @@ qla2xxx_eh_abort(struct scsi_cmnd *cmd)
                return ret;
 
        sp = scsi_cmd_priv(cmd);
+       qpair = sp->qpair;
 
-       /* Return if the command has already finished. */
-       if (sp_get(sp))
+       if ((sp->fcport && sp->fcport->deleted) || !qpair)
                return SUCCESS;
 
+       spin_lock_irqsave(qpair->qp_lock_ptr, flags);
+       if (sp->completed) {
+               spin_unlock_irqrestore(qpair->qp_lock_ptr, flags);
+               return SUCCESS;
+       }
+
+       if (sp->abort || sp->aborted) {
+               spin_unlock_irqrestore(qpair->qp_lock_ptr, flags);
+               return FAILED;
+       }
+
+       sp->abort = 1;
+       sp->comp = ∁
+       spin_unlock_irqrestore(qpair->qp_lock_ptr, flags);
+
+
        id = cmd->device->id;
        lun = cmd->device->lun;
 
@@ -1296,47 +1293,37 @@ qla2xxx_eh_abort(struct scsi_cmnd *cmd)
            "Aborting from RISC nexus=%ld:%d:%llu sp=%p cmd=%p handle=%x\n",
            vha->host_no, id, lun, sp, cmd, sp->handle);
 
+       /*
+        * Abort will release the original Command/sp from FW. Let the
+        * original command call scsi_done. In return, he will wakeup
+        * this sleeping thread.
+        */
        rval = ha->isp_ops->abort_command(sp);
+
        ql_dbg(ql_dbg_taskm, vha, 0x8003,
               "Abort command mbx cmd=%p, rval=%x.\n", cmd, rval);
 
+       /* Wait for the command completion. */
+       ratov_j = ha->r_a_tov/10 * 4 * 1000;
+       ratov_j = msecs_to_jiffies(ratov_j);
        switch (rval) {
        case QLA_SUCCESS:
-               /*
-                * The command has been aborted. That means that the firmware
-                * won't report a completion.
-                */
-               sp->done(sp, DID_ABORT << 16);
-               ret = SUCCESS;
-               break;
-       case QLA_FUNCTION_PARAMETER_ERROR: {
-               /* Wait for the command completion. */
-               uint32_t ratov = ha->r_a_tov/10;
-               uint32_t ratov_j = msecs_to_jiffies(4 * ratov * 1000);
-
-               WARN_ON_ONCE(sp->comp);
-               sp->comp = &comp;
                if (!wait_for_completion_timeout(&comp, ratov_j)) {
                        ql_dbg(ql_dbg_taskm, vha, 0xffff,
                            "%s: Abort wait timer (4 * R_A_TOV[%d]) expired\n",
-                           __func__, ha->r_a_tov);
+                           __func__, ha->r_a_tov/10);
                        ret = FAILED;
                } else {
                        ret = SUCCESS;
                }
                break;
-       }
        default:
-               /*
-                * Either abort failed or abort and completion raced. Let
-                * the SCSI core retry the abort in the former case.
-                */
                ret = FAILED;
                break;
        }
 
        sp->comp = NULL;
-       atomic_dec(&sp->ref_count);
+
        ql_log(ql_log_info, vha, 0x801c,
            "Abort command issued nexus=%ld:%d:%llu -- %x.\n",
            vha->host_no, id, lun, ret);
@@ -1719,32 +1706,53 @@ static void qla2x00_abort_srb(struct qla_qpair *qp, srb_t *sp, const int res,
        scsi_qla_host_t *vha = qp->vha;
        struct qla_hw_data *ha = vha->hw;
        int rval;
+       bool ret_cmd;
+       uint32_t ratov_j;
 
-       if (sp_get(sp))
+       if (qla2x00_chip_is_down(vha)) {
+               sp->done(sp, res);
                return;
+       }
 
        if (sp->type == SRB_NVME_CMD || sp->type == SRB_NVME_LS ||
            (sp->type == SRB_SCSI_CMD && !ha->flags.eeh_busy &&
             !test_bit(ABORT_ISP_ACTIVE, &vha->dpc_flags) &&
             !qla2x00_isp_reg_stat(ha))) {
+               if (sp->comp) {
+                       sp->done(sp, res);
+                       return;
+               }
+
                sp->comp = &comp;
+               sp->abort =  1;
                spin_unlock_irqrestore(qp->qp_lock_ptr, *flags);
-               rval = ha->isp_ops->abort_command(sp);
 
+               rval = ha->isp_ops->abort_command(sp);
+               /* Wait for command completion. */
+               ret_cmd = false;
+               ratov_j = ha->r_a_tov/10 * 4 * 1000;
+               ratov_j = msecs_to_jiffies(ratov_j);
                switch (rval) {
                case QLA_SUCCESS:
-                       sp->done(sp, res);
+                       if (wait_for_completion_timeout(&comp, ratov_j)) {
+                               ql_dbg(ql_dbg_taskm, vha, 0xffff,
+                                   "%s: Abort wait timer (4 * R_A_TOV[%d]) expired\n",
+                                   __func__, ha->r_a_tov/10);
+                               ret_cmd = true;
+                       }
+                       /* else FW return SP to driver */
                        break;
-               case QLA_FUNCTION_PARAMETER_ERROR:
-                       wait_for_completion(&comp);
+               default:
+                       ret_cmd = true;
                        break;
                }
 
                spin_lock_irqsave(qp->qp_lock_ptr, *flags);
-               sp->comp = NULL;
+               if (ret_cmd && (!sp->completed || !sp->aborted))
+                       sp->done(sp, res);
+       } else {
+               sp->done(sp, res);
        }
-
-       atomic_dec(&sp->ref_count);
 }
 
 static void
@@ -1766,7 +1774,6 @@ __qla2x00_abort_all_cmds(struct qla_qpair *qp, int res)
        for (cnt = 1; cnt < req->num_outstanding_cmds; cnt++) {
                sp = req->outstanding_cmds[cnt];
                if (sp) {
-                       req->outstanding_cmds[cnt] = NULL;
                        switch (sp->cmd_type) {
                        case TYPE_SRB:
                                qla2x00_abort_srb(qp, sp, res, &flags);
@@ -1788,6 +1795,7 @@ __qla2x00_abort_all_cmds(struct qla_qpair *qp, int res)
                        default:
                                break;
                        }
+                       req->outstanding_cmds[cnt] = NULL;
                }
        }
        spin_unlock_irqrestore(qp->qp_lock_ptr, flags);