> directly call __irq_domain_alloc_irqs() in hpet_assign_irq() and pass > correct `arg' to fix the oops. >
oh, what I was thinking about... it should be as simple as this. 8<-----8<----- >From 8be2eb548cefc788c87b05da22176b7360c6aca9 Mon Sep 17 00:00:00 2001 From: Sergey Senozhatsky <[email protected]> Date: Mon, 11 May 2015 18:56:49 +0900 Subject: [PATCH] x86/hpet: fix NULL pointer deference in msi_domain_alloc_irqs() Fix the following oops: hpet_msi_get_hwirq+0x1f/0x27 msi_domain_alloc+0x35/0xfe ? trace_hardirqs_on_caller+0x16c/0x188 irq_domain_alloc_irqs_recursive+0x51/0x95 __irq_domain_alloc_irqs+0x151/0x223 hpet_assign_irq+0x5d/0x68 hpet_msi_capability_lookup+0x121/0x1cb ? hpet_enable+0x2b4/0x2b4 hpet_late_init+0x5f/0xf2 ? hpet_enable+0x2b4/0x2b4 do_one_initcall+0x184/0x199 kernel_init_freeable+0x1af/0x237 ? rest_init+0x13a/0x13a kernel_init+0xe/0xd4 ret_from_fork+0x3f/0x70 ? rest_init+0x13a/0x13a since 3cb96f0c9733 ('x86/hpet: Enhance HPET IRQ to support hierarchical irqdomains') hpet_msi_capability_lookup() uses hpet_assign_irq(). the latter discards `irq_alloc_info info' param and instead passes NULL to __irq_domain_alloc_irqs() as `arg'. __irq_domain_alloc_irqs() invokes irq_domain_alloc_irqs_recursive(), which msi_domain_alloc_irqs() and, eventually, accesses `arg->hpet_index' in hpet_msi_get_hwirq(). pass a correct `irq_alloc_info info' pointer to irq_domain_alloc_irqs() in hpet_assign_irq() to fix the oops. Signed-off-by: Sergey Senozhatsky <[email protected]> --- arch/x86/kernel/apic/msi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/apic/msi.c b/arch/x86/kernel/apic/msi.c index 58fde66..ef516af 100644 --- a/arch/x86/kernel/apic/msi.c +++ b/arch/x86/kernel/apic/msi.c @@ -351,6 +351,6 @@ int hpet_assign_irq(struct irq_domain *domain, struct hpet_dev *dev, info.hpet_id = hpet_dev_id(domain); info.hpet_index = dev_num; - return irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, NULL); + return irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, &info); } #endif -- 2.4.0.rc3.3.g6eb1401 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
