scsi: aacraid: Fix memory leak in fib init path

commit 1bff5abc upstream.

aac_fib_map_free frees misaligned fib dma memory, additionally it does not
free up the whole memory.

Fixed by changing the  code to free up the correct and full memory
allocation.

Fixes: e8b12f0f ([SCSI] aacraid: Add new code for PMC-Sierra's SRC based controller family)
Signed-off-by: Raghava Aditya Renukunta <RaghavaAditya.Renukunta@microsemi.com>
Reviewed-by: David Carroll <David.Carroll@microsemi.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
[bwh: Backported to 3.16: s/max_cmd_size/max_fib_size/]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/scsi/aacraid/commsup.c

@@ -83,12 +83,20 @@ static int fib_map_alloc(struct aac_dev *dev)
 
 void aac_fib_map_free(struct aac_dev *dev)
 {
-	if (dev->hw_fib_va && dev->max_fib_size) {
-		pci_free_consistent(dev->pdev,
-		(dev->max_fib_size *
-		(dev->scsi_host_ptr->can_queue + AAC_NUM_MGT_FIB)),
-		dev->hw_fib_va, dev->hw_fib_pa);
-	}
+	size_t alloc_size;
+	size_t fib_size;
+	int num_fibs;
+
+	if(!dev->hw_fib_va || !dev->max_fib_size)
+		return;
+
+	num_fibs = dev->scsi_host_ptr->can_queue + AAC_NUM_MGT_FIB;
+	fib_size = dev->max_fib_size + sizeof(struct aac_fib_xporthdr);
+	alloc_size = fib_size * num_fibs + ALIGN32 - 1;
+
+	pci_free_consistent(dev->pdev, alloc_size, dev->hw_fib_va,
+							dev->hw_fib_pa);
+
 	dev->hw_fib_va = NULL;
 	dev->hw_fib_pa = 0;
 }
@@ -116,22 +124,20 @@ int aac_fib_setup(struct aac_dev * dev)
 	if (i<0)
 		return -ENOMEM;
 
-	/* 32 byte alignment for PMC */
-	hw_fib_pa = (dev->hw_fib_pa + (ALIGN32 - 1)) & ~(ALIGN32 - 1);
-	dev->hw_fib_va = (struct hw_fib *)((unsigned char *)dev->hw_fib_va +
-		(hw_fib_pa - dev->hw_fib_pa));
-	dev->hw_fib_pa = hw_fib_pa;
 	memset(dev->hw_fib_va, 0,
 		(dev->max_fib_size + sizeof(struct aac_fib_xporthdr)) *
 		(dev->scsi_host_ptr->can_queue + AAC_NUM_MGT_FIB));
 
+	/* 32 byte alignment for PMC */
+	hw_fib_pa = (dev->hw_fib_pa + (ALIGN32 - 1)) & ~(ALIGN32 - 1);
+	hw_fib    = (struct hw_fib *)((unsigned char *)dev->hw_fib_va +
+					(hw_fib_pa - dev->hw_fib_pa));
+
 	/* add Xport header */
-	dev->hw_fib_va = (struct hw_fib *)((unsigned char *)dev->hw_fib_va +
+	hw_fib = (struct hw_fib *)((unsigned char *)hw_fib +
 		sizeof(struct aac_fib_xporthdr));
-	dev->hw_fib_pa += sizeof(struct aac_fib_xporthdr);
+	hw_fib_pa += sizeof(struct aac_fib_xporthdr);
 
-	hw_fib = dev->hw_fib_va;
-	hw_fib_pa = dev->hw_fib_pa;
 	/*
 	 *	Initialise the fibs
 	 */