From 880799fc7a3a127c43143935c1a8767d77c19cae Mon Sep 17 00:00:00 2001 From: Maxime Chevallier Date: Fri, 23 Aug 2024 12:07:12 +0200 Subject: [PATCH] irqchip/irq-msi-lib: Check for NULL ops in msi_lib_irq_domain_select() The irq_domain passed to msi_lib_irq_domain_select() may not have msi_parent_ops set. There is a NULL pointer check for it, but unfortunately there is a dereference of the parent ops pointer before that. Move the NULL pointer test before the first use of that pointer. This was found on a MacchiatoBin (Marvell Armada 8K SoC), which uses the irq-mvebu-sei driver. Fixes: 72e257c6f058 ("irqchip: Provide irq-msi-lib") Signed-off-by: Maxime Chevallier Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20240823100733.1900666-1-maxime.chevallier@bootlin.com Closes: https://lore.kernel.org/all/20240821165034.1af97bad@fedora-3.home/ --- drivers/irqchip/irq-msi-lib.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/irqchip/irq-msi-lib.c b/drivers/irqchip/irq-msi-lib.c index b5b90003311a1..d8e29fc0d4068 100644 --- a/drivers/irqchip/irq-msi-lib.c +++ b/drivers/irqchip/irq-msi-lib.c @@ -128,6 +128,9 @@ int msi_lib_irq_domain_select(struct irq_domain *d, struct irq_fwspec *fwspec, const struct msi_parent_ops *ops = d->msi_parent_ops; u32 busmask = BIT(bus_token); + if (!ops) + return 0; + if (fwspec->fwnode != d->fwnode || fwspec->param_count != 0) return 0; @@ -135,6 +138,6 @@ int msi_lib_irq_domain_select(struct irq_domain *d, struct irq_fwspec *fwspec, if (bus_token == ops->bus_select_token) return 1; - return ops && !!(ops->bus_select_mask & busmask); + return !!(ops->bus_select_mask & busmask); } EXPORT_SYMBOL_GPL(msi_lib_irq_domain_select);