| Message ID | 1508505442-30352-2-git-send-email-dougmill@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
Douglas, > On error, kthread_create() returns an errno-encoded pointer, not NULL. > The routine qla2x00_probe_one() detects the error case and jumps > to probe_failed, but has already assigned the return value from > kthread_create() to ha->dpc_thread. Then probe_failed checks to see > if ha->dpc_thread is not NULL before doing cleanup on it. Since in the > error case this is also not NULL, it ends up trying to access an invalid > task pointer. > > Solution is to assign NULL to ha->dpc_thread in the error path to avoid > kthread cleanup in that case. QLogic folks: Please review!
> On Oct 20, 2017, at 6:17 AM, Douglas Miller <dougmill@linux.vnet.ibm.com> wrote: > > On error, kthread_create() returns an errno-encoded pointer, not NULL. > The routine qla2x00_probe_one() detects the error case and jumps > to probe_failed, but has already assigned the return value from > kthread_create() to ha->dpc_thread. Then probe_failed checks to see > if ha->dpc_thread is not NULL before doing cleanup on it. Since in the > error case this is also not NULL, it ends up trying to access an invalid > task pointer. > > Solution is to assign NULL to ha->dpc_thread in the error path to avoid > kthread cleanup in that case. > > Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> > --- > drivers/scsi/qla2xxx/qla_os.c | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c > index 9372098..bd39bf2 100644 > --- a/drivers/scsi/qla2xxx/qla_os.c > +++ b/drivers/scsi/qla2xxx/qla_os.c > @@ -3212,6 +3212,7 @@ static void qla2x00_iocb_work_fn(struct work_struct *work) > ql_log(ql_log_fatal, base_vha, 0x00ed, > "Failed to start DPC thread.\n"); > ret = PTR_ERR(ha->dpc_thread); > + ha->dpc_thread = NULL; > goto probe_failed; > } > ql_dbg(ql_dbg_init, base_vha, 0x00ee, > -- > 1.7.1 > Looks good. Acked-by: Himanshu Madhani <himanshu.madhani@cavium.com> Thanks, - Himanshu
Douglas, > On error, kthread_create() returns an errno-encoded pointer, not NULL. > The routine qla2x00_probe_one() detects the error case and jumps > to probe_failed, but has already assigned the return value from > kthread_create() to ha->dpc_thread. Then probe_failed checks to see > if ha->dpc_thread is not NULL before doing cleanup on it. Since in the > error case this is also not NULL, it ends up trying to access an invalid > task pointer. > > Solution is to assign NULL to ha->dpc_thread in the error path to avoid > kthread cleanup in that case. Applied to 4.14/scsi-fixes. Thank you!
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c index 9372098..bd39bf2 100644 --- a/drivers/scsi/qla2xxx/qla_os.c +++ b/drivers/scsi/qla2xxx/qla_os.c @@ -3212,6 +3212,7 @@ static void qla2x00_iocb_work_fn(struct work_struct *work) ql_log(ql_log_fatal, base_vha, 0x00ed, "Failed to start DPC thread.\n"); ret = PTR_ERR(ha->dpc_thread); + ha->dpc_thread = NULL; goto probe_failed; } ql_dbg(ql_dbg_init, base_vha, 0x00ee,
On error, kthread_create() returns an errno-encoded pointer, not NULL. The routine qla2x00_probe_one() detects the error case and jumps to probe_failed, but has already assigned the return value from kthread_create() to ha->dpc_thread. Then probe_failed checks to see if ha->dpc_thread is not NULL before doing cleanup on it. Since in the error case this is also not NULL, it ends up trying to access an invalid task pointer. Solution is to assign NULL to ha->dpc_thread in the error path to avoid kthread cleanup in that case. Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> --- drivers/scsi/qla2xxx/qla_os.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-)