From f9e8894ae5157796dd69249c56062042d02a431d Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Thu, 18 Mar 2010 15:39:30 -0400 Subject: [PATCH] [SCSI] fix race in scsi_target_reap This patch (as1357) fixes a race in SCSI target allocation and release. Putting a target in the STARGET_DEL state isn't protected by the host lock, so an old target structure could be reused by a new device even though it's about to be deleted. The cure is to change the state while still holding the host lock. Signed-off-by: Alan Stern Signed-off-by: James Bottomley --- drivers/scsi/scsi_scan.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index c992ecf4e372..a77468cd5a33 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -492,19 +492,20 @@ void scsi_target_reap(struct scsi_target *starget) struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); unsigned long flags; enum scsi_target_state state; - int empty; + int empty = 0; spin_lock_irqsave(shost->host_lock, flags); state = starget->state; - empty = --starget->reap_ref == 0 && - list_empty(&starget->devices) ? 1 : 0; + if (--starget->reap_ref == 0 && list_empty(&starget->devices)) { + empty = 1; + starget->state = STARGET_DEL; + } spin_unlock_irqrestore(shost->host_lock, flags); if (!empty) return; BUG_ON(state == STARGET_DEL); - starget->state = STARGET_DEL; if (state == STARGET_CREATED) scsi_target_destroy(starget); else -- 2.20.1