Blob Blame History Raw
From f84afbdd3a9e5e10633695677b95422572f920dc Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Tue, 25 Feb 2020 19:20:56 +0300
Subject: [PATCH] libnvdimm: Out of bounds read in __nd_ioctl()

References: bsc#1065729
Patch-mainline: v5.7-rc1
Git-commit: f84afbdd3a9e5e10633695677b95422572f920dc

The "cmd" comes from the user and it can be up to 255.  It it's more
than the number of bits in long, it results out of bounds read when we
check test_bit(cmd, &cmd_mask).  The highest valid value for "cmd" is
ND_CMD_CALL (10) so I added a compare against that.

Fixes: 62232e45f4a2 ("libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200225162055.amtosfy7m35aivxg@kili.mountain
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 drivers/nvdimm/bus.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index a8b5159685699..09087c38fabdc 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -1042,8 +1042,10 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
 			return -EFAULT;
 	}
 
-	if (!desc || (desc->out_num + desc->in_num == 0) ||
-			!test_bit(cmd, &cmd_mask))
+	if (!desc ||
+	    (desc->out_num + desc->in_num == 0) ||
+	    cmd > ND_CMD_CALL ||
+	    !test_bit(cmd, &cmd_mask))
 		return -ENOTTY;
 
 	/* fail write commands (when read-only) */
-- 
2.16.4