From: Marc Zyngier Date: Sun, 29 Nov 2020 13:55:51 +0000 (+0000) Subject: genirq/irqdomain: Don't try to free an interrupt that has no mapping X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4615fbc3788ddc8e7c6d697714ad35a53729aa2c;p=linux.git genirq/irqdomain: Don't try to free an interrupt that has no mapping When an interrupt allocation fails for N interrupts, it is pretty common for the error handling code to free the same number of interrupts, no matter how many interrupts have actually been allocated. This may result in the domain freeing code to be unexpectedly called for interrupts that have no mapping in that domain. Things end pretty badly. Instead, add some checks to irq_domain_free_irqs_hierarchy() to make sure that thiss does not follow the hierarchy if no mapping exists for a given interrupt. Fixes: 6a6544e520abe ("genirq/irqdomain: Remove auto-recursive hierarchy support") Signed-off-by: Marc Zyngier Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20201129135551.396777-1-maz@kernel.org --- diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 3d7463fd64532..30a78872a5cf3 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -1381,8 +1381,15 @@ static void irq_domain_free_irqs_hierarchy(struct irq_domain *domain, unsigned int irq_base, unsigned int nr_irqs) { - if (domain->ops->free) - domain->ops->free(domain, irq_base, nr_irqs); + unsigned int i; + + if (!domain->ops->free) + return; + + for (i = 0; i < nr_irqs; i++) { + if (irq_domain_get_irq_data(domain, irq_base + i)) + domain->ops->free(domain, irq_base + i, 1); + } } int irq_domain_alloc_irqs_hierarchy(struct irq_domain *domain,