| Message ID | 20170519215344.2168-3-himanshu.madhani@cavium.com (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
On Fri, 2017-05-19 at 14:53 -0700, Himanshu Madhani wrote: > From: Quinn Tran <quinn.tran@cavium.com> > > Remove redundant fc_host_port_name calls to prevent > early access of scsi_host->shost_data buffer. This > prevent null pointer access. > > Cc: <stable@vger.kernel.org> > Signed-off-by: Quinn Tran <quinn.tran@cavium.com> > Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com> > --- > drivers/scsi/qla2xxx/qla_mbx.c | 9 --------- > 1 file changed, 9 deletions(-) > > diff --git a/drivers/scsi/qla2xxx/qla_mbx.c b/drivers/scsi/qla2xxx/qla_mbx.c > index a113ab3592a7..12fea77e31c6 100644 > --- a/drivers/scsi/qla2xxx/qla_mbx.c > +++ b/drivers/scsi/qla2xxx/qla_mbx.c > @@ -3676,15 +3676,6 @@ qla24xx_report_id_acquisition(scsi_qla_host_t *vha, > qlt_update_host_map(vha, id); > } > > - fc_host_port_name(vha->host) = > - wwn_to_u64(vha->port_name); > - > - if (qla_ini_mode_enabled(vha)) > - ql_dbg(ql_dbg_mbx, vha, 0x1018, > - "FA-WWN portname %016llx (%x)\n", > - fc_host_port_name(vha->host), > - rptid_entry->vp_status); > - > set_bit(REGISTER_FC4_NEEDED, &vha->dpc_flags); > set_bit(REGISTER_FDMI_NEEDED, &vha->dpc_flags); > } else { Hello Himanshu, If the above host port name assignment is redundant, what is the host port name assignment it is redundant with? Which of the removed statements could trigger a NULL pointer access, and from what context? Is there perhaps a call trace available of the NULL pointer access? Thanks, Bart.
Hi Bart, > On May 19, 2017, at 3:37 PM, Bart Van Assche <bart.vanassche@sandisk.com> wrote: > > On Fri, 2017-05-19 at 14:53 -0700, Himanshu Madhani wrote: >> From: Quinn Tran <quinn.tran@cavium.com> >> >> Remove redundant fc_host_port_name calls to prevent >> early access of scsi_host->shost_data buffer. This >> prevent null pointer access. >> >> Cc: <stable@vger.kernel.org> >> Signed-off-by: Quinn Tran <quinn.tran@cavium.com> >> Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com> >> --- >> drivers/scsi/qla2xxx/qla_mbx.c | 9 --------- >> 1 file changed, 9 deletions(-) >> >> diff --git a/drivers/scsi/qla2xxx/qla_mbx.c b/drivers/scsi/qla2xxx/qla_mbx.c >> index a113ab3592a7..12fea77e31c6 100644 >> --- a/drivers/scsi/qla2xxx/qla_mbx.c >> +++ b/drivers/scsi/qla2xxx/qla_mbx.c >> @@ -3676,15 +3676,6 @@ qla24xx_report_id_acquisition(scsi_qla_host_t *vha, >> qlt_update_host_map(vha, id); >> } >> >> - fc_host_port_name(vha->host) = >> - wwn_to_u64(vha->port_name); >> - >> - if (qla_ini_mode_enabled(vha)) >> - ql_dbg(ql_dbg_mbx, vha, 0x1018, >> - "FA-WWN portname %016llx (%x)\n", >> - fc_host_port_name(vha->host), >> - rptid_entry->vp_status); >> - >> set_bit(REGISTER_FC4_NEEDED, &vha->dpc_flags); >> set_bit(REGISTER_FDMI_NEEDED, &vha->dpc_flags); >> } else { > > Hello Himanshu, > > If the above host port name assignment is redundant, what is the host > port name assignment it is redundant with? > > Which of the removed statements could trigger a NULL pointer access, and > from what context? Is there perhaps a call trace available of the NULL > pointer access? > > Thanks, > > Bart. We see following NULL pointer access on a faster systems. So far its has been only seen on couple systems in our env. [ 498.637517] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 498.637572] IP: qla24xx_report_id_acquisition+0x22d/0x3a0 [qla2xxx] GDB showed following lines were causing NULL pointer deference. (gdb) l *qla24xx_report_id_acquisition+0x22d 0x2012d is in qla24xx_report_id_acquisition (drivers/scsi/qla2xxx/qla_mbx.c:3679). 3674 } 3675 3676 qlt_update_host_map(vha, id); 3677 } 3678 3679 fc_host_port_name(vha->host) = 3680 wwn_to_u64(vha->port_name); 3681 3682 if (qla_ini_mode_enabled(vha)) 3683 ql_dbg(ql_dbg_mbx, vha, 0x1018, (gdb) Thanks, - Himanshu
diff --git a/drivers/scsi/qla2xxx/qla_mbx.c b/drivers/scsi/qla2xxx/qla_mbx.c index a113ab3592a7..12fea77e31c6 100644 --- a/drivers/scsi/qla2xxx/qla_mbx.c +++ b/drivers/scsi/qla2xxx/qla_mbx.c @@ -3676,15 +3676,6 @@ qla24xx_report_id_acquisition(scsi_qla_host_t *vha, qlt_update_host_map(vha, id); } - fc_host_port_name(vha->host) = - wwn_to_u64(vha->port_name); - - if (qla_ini_mode_enabled(vha)) - ql_dbg(ql_dbg_mbx, vha, 0x1018, - "FA-WWN portname %016llx (%x)\n", - fc_host_port_name(vha->host), - rptid_entry->vp_status); - set_bit(REGISTER_FC4_NEEDED, &vha->dpc_flags); set_bit(REGISTER_FDMI_NEEDED, &vha->dpc_flags); } else {