[PATCH AUTOSEL 5.10 23/53] scsi: qla2xxx: Fix unsafe removal from linked list

From: Sasha Levin
Date: Thu Sep 09 2021 - 20:54:52 EST


From: Quinn Tran <qutran@xxxxxxxxxxx>

[ Upstream commit 0c9a5f3e42f75dbad5966aa59db935b694ab00d1 ]

On NPIV delete, the VPort is taken off a linked list in an unsafe manner.
The check for VPort refcount should be done behind lock before taking off
the element.

[ 2733.016907] general protection fault: 0000 [#1] SMP NOPTI
[ 2733.016908] qla2xxx [0000:22:00.1]-7088:27: VP[4] deleted.
[ 2733.016912] CPU: 22 PID: 23481 Comm: qla2xxx_15_dpc Kdump: loaded Tainted:
G OE KX 5.3.18-47-default #1 SLE15-SP3
[ 2733.016914] Hardware name: Dell Inc. PowerEdge R7525/0PYVT1, BIOS 2.1.4 02/17/2021
[ 2733.016929] RIP: 0010:qla2x00_abort_isp+0x90/0x850 [qla2xxx]
[ 2733.016933] RSP: 0018:ffffb9cfc91efe98 EFLAGS: 00010087
[ 2733.016935] RAX: 0000000000000292 RBX: dead000000000100 RCX: 0000000000000000
[ 2733.016936] RDX: 0000000000000001 RSI: ffff944bfeb99558 RDI: ffff944bfc4b4488
[ 2733.016937] RBP: ffff944bfc4b2868 R08: 00000000000187a2 R09: 0000000000000001
[ 2733.016937] R10: ffffb9cfc91efcc8 R11: 0000000000000001 R12: ffff944bfc4b4000
[ 2733.016938] R13: ffff944bfc4b4870 R14: ffff944bfc4b4488 R15: ffff944bda895c80
[ 2733.016939] FS: 0000000000000000(0000) GS:ffff944bfeb80000(0000) knlGS:0000000000000000
[ 2733.016940] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2733.016940] CR2: 00007fc173e74458 CR3: 0000001ff57de000 CR4: 0000000000350ee0
[ 2733.016941] Call Trace:
[ 2733.016951] qla2xxx_pci_error_detected+0x190/0x190 [qla2xxx]
[ 2733.016957] qla2x00_do_dpc+0x560/0xa10 [qla2xxx]
[ 2733.016962] kthread+0x10d/0x130
[ 2733.016963] kthread_park+0xa0/0xa0
[ 2733.016966] ret_from_fork+0x22/0x40

Link: https://lore.kernel.org/r/20210810043720.1137-9-njavali@xxxxxxxxxxx
Reviewed-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>
Signed-off-by: Quinn Tran <qutran@xxxxxxxxxxx>
Signed-off-by: Nilesh Javali <njavali@xxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/scsi/qla2xxx/qla_init.c | 33 +++++++++++++++++---------
drivers/scsi/qla2xxx/qla_mid.c | 42 ++++++++++++++++++++-------------
drivers/scsi/qla2xxx/qla_os.c | 6 ++---
3 files changed, 50 insertions(+), 31 deletions(-)

diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
index 6faf34fa6220..9d51ef4eae3f 100644
--- a/drivers/scsi/qla2xxx/qla_init.c
+++ b/drivers/scsi/qla2xxx/qla_init.c
@@ -6388,13 +6388,13 @@ void
qla2x00_update_fcports(scsi_qla_host_t *base_vha)
{
fc_port_t *fcport;
- struct scsi_qla_host *vha;
+ struct scsi_qla_host *vha, *tvp;
struct qla_hw_data *ha = base_vha->hw;
unsigned long flags;

spin_lock_irqsave(&ha->vport_slock, flags);
/* Go with deferred removal of rport references. */
- list_for_each_entry(vha, &base_vha->hw->vp_list, list) {
+ list_for_each_entry_safe(vha, tvp, &base_vha->hw->vp_list, list) {
atomic_inc(&vha->vref_count);
list_for_each_entry(fcport, &vha->vp_fcports, list) {
if (fcport->drport &&
@@ -6739,7 +6739,8 @@ void
qla2x00_quiesce_io(scsi_qla_host_t *vha)
{
struct qla_hw_data *ha = vha->hw;
- struct scsi_qla_host *vp;
+ struct scsi_qla_host *vp, *tvp;
+ unsigned long flags;

ql_dbg(ql_dbg_dpc, vha, 0x401d,
"Quiescing I/O - ha=%p.\n", ha);
@@ -6748,8 +6749,18 @@ qla2x00_quiesce_io(scsi_qla_host_t *vha)
if (atomic_read(&vha->loop_state) != LOOP_DOWN) {
atomic_set(&vha->loop_state, LOOP_DOWN);
qla2x00_mark_all_devices_lost(vha);
- list_for_each_entry(vp, &ha->vp_list, list)
+
+ spin_lock_irqsave(&ha->vport_slock, flags);
+ list_for_each_entry_safe(vp, tvp, &ha->vp_list, list) {
+ atomic_inc(&vp->vref_count);
+ spin_unlock_irqrestore(&ha->vport_slock, flags);
+
qla2x00_mark_all_devices_lost(vp);
+
+ spin_lock_irqsave(&ha->vport_slock, flags);
+ atomic_dec(&vp->vref_count);
+ }
+ spin_unlock_irqrestore(&ha->vport_slock, flags);
} else {
if (!atomic_read(&vha->loop_down_timer))
atomic_set(&vha->loop_down_timer,
@@ -6764,7 +6775,7 @@ void
qla2x00_abort_isp_cleanup(scsi_qla_host_t *vha)
{
struct qla_hw_data *ha = vha->hw;
- struct scsi_qla_host *vp;
+ struct scsi_qla_host *vp, *tvp;
unsigned long flags;
fc_port_t *fcport;
u16 i;
@@ -6828,7 +6839,7 @@ qla2x00_abort_isp_cleanup(scsi_qla_host_t *vha)
qla2x00_mark_all_devices_lost(vha);

spin_lock_irqsave(&ha->vport_slock, flags);
- list_for_each_entry(vp, &ha->vp_list, list) {
+ list_for_each_entry_safe(vp, tvp, &ha->vp_list, list) {
atomic_inc(&vp->vref_count);
spin_unlock_irqrestore(&ha->vport_slock, flags);

@@ -6850,7 +6861,7 @@ qla2x00_abort_isp_cleanup(scsi_qla_host_t *vha)
fcport->scan_state = 0;
}
spin_lock_irqsave(&ha->vport_slock, flags);
- list_for_each_entry(vp, &ha->vp_list, list) {
+ list_for_each_entry_safe(vp, tvp, &ha->vp_list, list) {
atomic_inc(&vp->vref_count);
spin_unlock_irqrestore(&ha->vport_slock, flags);

@@ -6898,7 +6909,7 @@ qla2x00_abort_isp(scsi_qla_host_t *vha)
int rval;
uint8_t status = 0;
struct qla_hw_data *ha = vha->hw;
- struct scsi_qla_host *vp;
+ struct scsi_qla_host *vp, *tvp;
struct req_que *req = ha->req_q_map[0];
unsigned long flags;

@@ -7030,7 +7041,7 @@ qla2x00_abort_isp(scsi_qla_host_t *vha)
ql_dbg(ql_dbg_taskm, vha, 0x8022, "%s succeeded.\n", __func__);
qla2x00_configure_hba(vha);
spin_lock_irqsave(&ha->vport_slock, flags);
- list_for_each_entry(vp, &ha->vp_list, list) {
+ list_for_each_entry_safe(vp, tvp, &ha->vp_list, list) {
if (vp->vp_idx) {
atomic_inc(&vp->vref_count);
spin_unlock_irqrestore(&ha->vport_slock, flags);
@@ -8719,7 +8730,7 @@ qla82xx_restart_isp(scsi_qla_host_t *vha)
{
int status, rval;
struct qla_hw_data *ha = vha->hw;
- struct scsi_qla_host *vp;
+ struct scsi_qla_host *vp, *tvp;
unsigned long flags;

status = qla2x00_init_rings(vha);
@@ -8791,7 +8802,7 @@ qla82xx_restart_isp(scsi_qla_host_t *vha)
"qla82xx_restart_isp succeeded.\n");

spin_lock_irqsave(&ha->vport_slock, flags);
- list_for_each_entry(vp, &ha->vp_list, list) {
+ list_for_each_entry_safe(vp, tvp, &ha->vp_list, list) {
if (vp->vp_idx) {
atomic_inc(&vp->vref_count);
spin_unlock_irqrestore(&ha->vport_slock, flags);
diff --git a/drivers/scsi/qla2xxx/qla_mid.c b/drivers/scsi/qla2xxx/qla_mid.c
index c7caf322f445..787e0c0446a6 100644
--- a/drivers/scsi/qla2xxx/qla_mid.c
+++ b/drivers/scsi/qla2xxx/qla_mid.c
@@ -65,7 +65,7 @@ qla24xx_deallocate_vp_id(scsi_qla_host_t *vha)
uint16_t vp_id;
struct qla_hw_data *ha = vha->hw;
unsigned long flags = 0;
- u8 i;
+ u32 i, bailout;

mutex_lock(&ha->vport_lock);
/*
@@ -75,21 +75,29 @@ qla24xx_deallocate_vp_id(scsi_qla_host_t *vha)
* ensures no active vp_list traversal while the vport is removed
* from the queue)
*/
- for (i = 0; i < 10; i++) {
- if (wait_event_timeout(vha->vref_waitq,
- !atomic_read(&vha->vref_count), HZ) > 0)
+ bailout = 0;
+ for (i = 0; i < 500; i++) {
+ spin_lock_irqsave(&ha->vport_slock, flags);
+ if (atomic_read(&vha->vref_count) == 0) {
+ list_del(&vha->list);
+ qlt_update_vp_map(vha, RESET_VP_IDX);
+ bailout = 1;
+ }
+ spin_unlock_irqrestore(&ha->vport_slock, flags);
+
+ if (bailout)
break;
+ else
+ msleep(20);
}
-
- spin_lock_irqsave(&ha->vport_slock, flags);
- if (atomic_read(&vha->vref_count)) {
- ql_dbg(ql_dbg_vport, vha, 0xfffa,
- "vha->vref_count=%u timeout\n", vha->vref_count.counter);
- vha->vref_count = (atomic_t)ATOMIC_INIT(0);
+ if (!bailout) {
+ ql_log(ql_log_info, vha, 0xfffa,
+ "vha->vref_count=%u timeout\n", vha->vref_count.counter);
+ spin_lock_irqsave(&ha->vport_slock, flags);
+ list_del(&vha->list);
+ qlt_update_vp_map(vha, RESET_VP_IDX);
+ spin_unlock_irqrestore(&ha->vport_slock, flags);
}
- list_del(&vha->list);
- qlt_update_vp_map(vha, RESET_VP_IDX);
- spin_unlock_irqrestore(&ha->vport_slock, flags);

vp_id = vha->vp_idx;
ha->num_vhosts--;
@@ -257,13 +265,13 @@ qla24xx_configure_vp(scsi_qla_host_t *vha)
void
qla2x00_alert_all_vps(struct rsp_que *rsp, uint16_t *mb)
{
- scsi_qla_host_t *vha;
+ scsi_qla_host_t *vha, *tvp;
struct qla_hw_data *ha = rsp->hw;
int i = 0;
unsigned long flags;

spin_lock_irqsave(&ha->vport_slock, flags);
- list_for_each_entry(vha, &ha->vp_list, list) {
+ list_for_each_entry_safe(vha, tvp, &ha->vp_list, list) {
if (vha->vp_idx) {
if (test_bit(VPORT_DELETE, &vha->dpc_flags))
continue;
@@ -416,7 +424,7 @@ void
qla2x00_do_dpc_all_vps(scsi_qla_host_t *vha)
{
struct qla_hw_data *ha = vha->hw;
- scsi_qla_host_t *vp;
+ scsi_qla_host_t *vp, *tvp;
unsigned long flags = 0;

if (vha->vp_idx)
@@ -430,7 +438,7 @@ qla2x00_do_dpc_all_vps(scsi_qla_host_t *vha)
return;

spin_lock_irqsave(&ha->vport_slock, flags);
- list_for_each_entry(vp, &ha->vp_list, list) {
+ list_for_each_entry_safe(vp, tvp, &ha->vp_list, list) {
if (vp->vp_idx) {
atomic_inc(&vp->vref_count);
spin_unlock_irqrestore(&ha->vport_slock, flags);
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 21be50b35bc2..dd734992c726 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -7366,7 +7366,7 @@ static void qla_pci_error_cleanup(scsi_qla_host_t *vha)
struct qla_hw_data *ha = vha->hw;
scsi_qla_host_t *base_vha = pci_get_drvdata(ha->pdev);
struct qla_qpair *qpair = NULL;
- struct scsi_qla_host *vp;
+ struct scsi_qla_host *vp, *tvp;
fc_port_t *fcport;
int i;
unsigned long flags;
@@ -7407,7 +7407,7 @@ static void qla_pci_error_cleanup(scsi_qla_host_t *vha)
qla2x00_mark_all_devices_lost(vha);

spin_lock_irqsave(&ha->vport_slock, flags);
- list_for_each_entry(vp, &ha->vp_list, list) {
+ list_for_each_entry_safe(vp, tvp, &ha->vp_list, list) {
atomic_inc(&vp->vref_count);
spin_unlock_irqrestore(&ha->vport_slock, flags);
qla2x00_mark_all_devices_lost(vp);
@@ -7421,7 +7421,7 @@ static void qla_pci_error_cleanup(scsi_qla_host_t *vha)
fcport->flags &= ~(FCF_LOGIN_NEEDED | FCF_ASYNC_SENT);

spin_lock_irqsave(&ha->vport_slock, flags);
- list_for_each_entry(vp, &ha->vp_list, list) {
+ list_for_each_entry_safe(vp, tvp, &ha->vp_list, list) {
atomic_inc(&vp->vref_count);
spin_unlock_irqrestore(&ha->vport_slock, flags);
list_for_each_entry(fcport, &vp->vp_fcports, list)
--
2.30.2