[PATCH AUTOSEL 5.3 84/89] virt: vbox: fix memory leak in hgcm_call_preprocess_linaddr

From: Sasha Levin
Date: Fri Oct 18 2019 - 18:23:40 EST


From: Navid Emamdoost <navid.emamdoost@xxxxxxxxx>

[ Upstream commit e0b0cb9388642c104838fac100a4af32745621e2 ]

In hgcm_call_preprocess_linaddr memory is allocated for bounce_buf but
is not released if copy_form_user fails. In order to prevent memory leak
in case of failure, the assignment to bounce_buf_ret is moved before the
error check. This way the allocated bounce_buf will be released by the
caller.

Fixes: 579db9d45cb4 ("virt: Add vboxguest VMMDEV communication code")
Signed-off-by: Navid Emamdoost <navid.emamdoost@xxxxxxxxx>
Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20190930204223.3660-1-navid.emamdoost@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/virt/vboxguest/vboxguest_utils.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/virt/vboxguest/vboxguest_utils.c b/drivers/virt/vboxguest/vboxguest_utils.c
index 75fd140b02ff8..43c391626a000 100644
--- a/drivers/virt/vboxguest/vboxguest_utils.c
+++ b/drivers/virt/vboxguest/vboxguest_utils.c
@@ -220,6 +220,8 @@ static int hgcm_call_preprocess_linaddr(
if (!bounce_buf)
return -ENOMEM;

+ *bounce_buf_ret = bounce_buf;
+
if (copy_in) {
ret = copy_from_user(bounce_buf, (void __user *)buf, len);
if (ret)
@@ -228,7 +230,6 @@ static int hgcm_call_preprocess_linaddr(
memset(bounce_buf, 0, len);
}

- *bounce_buf_ret = bounce_buf;
hgcm_call_add_pagelist_size(bounce_buf, len, extra);
return 0;
}
--
2.20.1