From: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Date: Sun, 27 Jun 2010 16:04:45 +0000 (+0900)
Subject: [SCSI] scsi_debug: fix map_region and unmap_region oops
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=9ab98f57b3e1d73cd0720d29c21b687ba609cde9;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

[SCSI] scsi_debug: fix map_region and unmap_region oops

map_region and unmap_region could access to invalid memory area since
they don't check the size boundary.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
---

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 136329b4027b..b02bdc6c2cd1 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -1991,7 +1991,8 @@ static void map_region(sector_t lba, unsigned int len)
 		block = lba + alignment;
 		rem = do_div(block, granularity);
 
-		set_bit(block, map_storep);
+		if (block < map_size)
+			set_bit(block, map_storep);
 
 		lba += granularity - rem;
 	}
@@ -2011,7 +2012,8 @@ static void unmap_region(sector_t lba, unsigned int len)
 		block = lba + alignment;
 		rem = do_div(block, granularity);
 
-		if (rem == 0 && lba + granularity <= end)
+		if (rem == 0 && lba + granularity <= end &&
+		    block < map_size)
 			clear_bit(block, map_storep);
 
 		lba += granularity - rem;