[SCSI] sym53c8xx: Fix NULL pointer dereference in slave_destroy

sym53c8xx_slave_destroy unconditionally assumes that sym53c8xx_slave_alloc has succesesfully allocated a sym_lcb. This can lead to a NULL pointer dereference (exposed by commit 4e6c82b). Signed-off-by: Stratos Psomadakis <psomas@gentoo.org> Cc: stable@vger.kernel.org Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] sym53c8xx: Fix NULL pointer dereference in slave_destroy
sym53c8xx_slave_destroy unconditionally assumes that sym53c8xx_slave_alloc has succesesfully allocated a sym_lcb. This can lead to a NULL pointer dereference (exposed by commit 4e6c82b). Signed-off-by: Stratos Psomadakis <psomas@gentoo.org> Cc: stable@vger.kernel.org Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Stratos Psomadakis · James Bottomley
1 parent 9fc397fc08
Showing 1 changed file with 4 additions and 0 deletions Side-by-side Diff
drivers/scsi/sym53c8xx_2/sym_glue.c
@@ -839,6 +839,10 @@
 	struct sym_lcb *lp = sym_lp(tp, sdev->lun);
 	unsigned long flags;
  
+	/* if slave_alloc returned before allocating a sym_lcb, return */
+	if (!lp)
+		return;
+
 	spin_lock_irqsave(np->s.host->host_lock, flags);
  
 	if (lp->busy_itlq || lp->busy_itl) {
...	...	@@ -839,6 +839,10 @@
839	839	struct sym_lcb *lp = sym_lp(tp, sdev->lun);
840	840	unsigned long flags;
841	841
	842	+ /* if slave_alloc returned before allocating a sym_lcb, return */
	843	+ if (!lp)
	844	+ return;
	845	+
842	846	spin_lock_irqsave(np->s.host->host_lock, flags);
843	847
844	848	if (lp->busy_itlq \|\| lp->busy_itl) {