From: Dan Carpenter Date: Thu, 7 Mar 2019 05:41:22 +0000 (+0300) Subject: xen, cpu_hotplug: Prevent an out of bounds access X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=201676095dda7e5b31a5e1d116d10fc22985075e;p=linux.git 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 Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross --- diff --git a/drivers/xen/cpu_hotplug.c b/drivers/xen/cpu_hotplug.c index b1357aa4bc552..f192b6f42da9f 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)) {