[SCSI] esp: Fix OOPS in esp_reset_cleanup().
OOPS reported by Friedrich Oslage <bluebird@porno-bullen.de>
The problem here is that tp->starget is set every time a lun
is allocated for a particular target so we can catch the
sdev_target parent value.
The reset handler uses the NULL'ness of this value to determine
which targets are active.
But esp_slave_destroy() does not NULL out this value when appropriate.
So for every target that doesn't respond, the SCSI bus scan causes
a stale pointer to be left here, with ensuing crashes like you're
seeing.
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/esp_scsi.c b/drivers/scsi/esp_scsi.c
index a0b6d41..305edde 100644
--- a/drivers/scsi/esp_scsi.c
+++ b/drivers/scsi/esp_scsi.c
@@ -2371,6 +2371,7 @@
dev->hostdata = lp;
tp->starget = dev->sdev_target;
+ tp->starget_ref++;
spi_min_period(tp->starget) = esp->min_period;
spi_max_offset(tp->starget) = 15;
@@ -2425,10 +2426,17 @@
static void esp_slave_destroy(struct scsi_device *dev)
{
+ struct esp *esp = shost_priv(dev->host);
+ struct esp_target_data *tp = &esp->target[dev->id];
struct esp_lun_data *lp = dev->hostdata;
kfree(lp);
dev->hostdata = NULL;
+
+ BUG_ON(tp->starget_ref <= 0);
+
+ if (!--tp->starget_ref)
+ tp->starget = NULL;
}
static int esp_eh_abort_handler(struct scsi_cmnd *cmd)