From: Marc Zyngier maz@kernel.org
[ Upstream commit 4615fbc3788ddc8e7c6d697714ad35a53729aa2c ]
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 maz@kernel.org Signed-off-by: Thomas Gleixner tglx@linutronix.de Link: https://lore.kernel.org/r/20201129135551.396777-1-maz@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/irq/irqdomain.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 0a76c44eb6b29..1e42fc2ad4d57 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -1247,8 +1247,15 @@ 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,