Commit-ID: 6cd0c583b04b2bd9415e07b51b63ab799949dd66 Gitweb: https://git.kernel.org/tip/6cd0c583b04b2bd9415e07b51b63ab799949dd66 Author: Yi Wang <[email protected]> AuthorDate: Mon, 23 Jul 2018 12:19:07 +0800 Committer: Ingo Molnar <[email protected]> CommitDate: Wed, 25 Jul 2018 11:25:07 +0200
sched/topology: Check variable group before dereferencing it The 'group' variable in sched_domain_debug_one() is not checked when firstly used in cpumask_test_cpu(cpu, sched_group_span(group)), but it might be NULL (it is checked later in the following while loop) and may cause NULL pointer dereference. We need to check it before using to avoid NULL dereference. Signed-off-by: Yi Wang <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Reviewed-by: Jiang Biao <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- kernel/sched/topology.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 05a831427bc7..56a0fed30c0a 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -47,7 +47,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) { printk(KERN_ERR "ERROR: domain->span does not contain CPU%d\n", cpu); } - if (!cpumask_test_cpu(cpu, sched_group_span(group))) { + if (group && !cpumask_test_cpu(cpu, sched_group_span(group))) { printk(KERN_ERR "ERROR: domain->groups does not contain CPU%d\n", cpu); }
