4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexey Dobriyan <adobriyan@xxxxxxxxx> commit 8fbbe2d7cc478d1544f41f2271787c993c23a4f6 upstream. Valid CPU ids are [0, nr_cpu_ids-1] inclusive. Fixes: 3b8e29a82dd1 ("genirq: Implement ipi_send_mask/single()") Fixes: f9bce791ae2a ("genirq: Add a new function to get IPI reverse mapping") Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/20170819095751.GB27864@avx2 Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/irq/ipi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/irq/ipi.c +++ b/kernel/irq/ipi.c @@ -165,7 +165,7 @@ irq_hw_number_t ipi_get_hwirq(unsigned i struct irq_data *data = irq_get_irq_data(irq); struct cpumask *ipimask = data ? irq_data_get_affinity_mask(data) : NULL; - if (!data || !ipimask || cpu > nr_cpu_ids) + if (!data || !ipimask || cpu >= nr_cpu_ids) return INVALID_HWIRQ; if (!cpumask_test_cpu(cpu, ipimask)) @@ -195,7 +195,7 @@ static int ipi_send_verify(struct irq_ch if (!chip->ipi_send_single && !chip->ipi_send_mask) return -EINVAL; - if (cpu > nr_cpu_ids) + if (cpu >= nr_cpu_ids) return -EINVAL; if (dest) {