[PATCH AUTOSEL 5.8 02/29] vboxsf: Fix the check for the old binary mount-arguments struct

Sasha Levin
2020-09-29T01:37:11Z

From: Hans de Goede <hdegoede@redhat.com>

[ Upstream commit 9d682ea6bcc76b8b2691c79add59f7d99c881635 ]

Fix the check for the mainline vboxsf code being used with the old
mount.vboxsf mount binary from the out-of-tree vboxsf version doing
a comparison between signed and unsigned data types.

This fixes the following smatch warnings:

fs/vboxsf/super.c:390 vboxsf_parse_monolithic() warn: impossible condition '(options[1] == (255)) => ((-128)-127 == 255)'
fs/vboxsf/super.c:391 vboxsf_parse_monolithic() warn: impossible condition '(options[2] == (254)) => ((-128)-127 == 254)'
fs/vboxsf/super.c:392 vboxsf_parse_monolithic() warn: impossible condition '(options[3] == (253)) => ((-128)-127 == 253)'

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/vboxsf/super.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
index 8fe03b4a0d2b0..25aade3441922 100644
--- a/fs/vboxsf/super.c
+++ b/fs/vboxsf/super.c
@@ -384,7 +384,7 @@ static int vboxsf_setup(void)

static int vboxsf_parse_monolithic(struct fs_context *fc, void *data)
{
- char *options = data;
+ unsigned char *options = data;

if (options && options[0] == VBSF_MOUNT_SIGNATURE_BYTE_0 &&
options[1] == VBSF_MOUNT_SIGNATURE_BYTE_1 &&
--
2.25.1