From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Thu, 7 Mar 2019 08:41:22 +0300
Patch-mainline: 5.1-rc1
Git-commit: 201676095dda7e5b31a5e1d116d10fc22985075e
References: bsc#1065600
Subject: [PATCH] xen, cpu_hotplug: Prevent an out of bounds access
The "cpu" variable comes from the sscanf() so Smatch marks it as
untrusted data. We can't pass a higher value than "nr_cpu_ids" to
cpu_possible() or it results in an out of bounds access.
Fixes: d68d82afd4c8 ("xen: implement CPU hotplugging")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
---
drivers/xen/cpu_hotplug.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/xen/cpu_hotplug.c b/drivers/xen/cpu_hotplug.c
index b1357aa4bc55..f192b6f42da9 100644
--- a/drivers/xen/cpu_hotplug.c
+++ b/drivers/xen/cpu_hotplug.c
@@ -54,7 +54,7 @@ static int vcpu_online(unsigned int cpu)
}
static void vcpu_hotplug(unsigned int cpu)
{
- if (!cpu_possible(cpu))
+ if (cpu >= nr_cpu_ids || !cpu_possible(cpu))
return;
switch (vcpu_online(cpu)) {
--
2.16.4