From 7fd1335392891188b022f5fa518201710d5be3ac Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 16 Jan 2018 12:20:18 +0100 Subject: x86/apic/vector: Fix off by one in error path commit 45d55e7bac4028af93f5fa324e69958a0b868e96 upstream. Keith reported the following warning: WARNING: CPU: 28 PID: 1420 at kernel/irq/matrix.c:222 irq_matrix_remove_managed+0x10f/0x120 x86_vector_free_irqs+0xa1/0x180 x86_vector_alloc_irqs+0x1e4/0x3a0 msi_domain_alloc+0x62/0x130 The reason for this is that if the vector allocation fails the error handling code tries to free the failed vector as well, which causes the above imbalance warning to trigger. Adjust the error path to handle this correctly. Fixes: b5dc8e6c21e7 ("x86/irq: Use hierarchical irqdomain to manage CPU interrupt vectors") Reported-by: Keith Busch Signed-off-by: Thomas Gleixner Tested-by: Keith Busch Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801161217300.1823@nanos Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/apic/vector.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'arch/x86/kernel/apic/vector.c') diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c index 0988e204f1e3..a41e523536a2 100644 --- a/arch/x86/kernel/apic/vector.c +++ b/arch/x86/kernel/apic/vector.c @@ -359,14 +359,17 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq, irq_data->chip_data = data; irq_data->hwirq = virq + i; err = assign_irq_vector_policy(virq + i, node, data, info); - if (err) + if (err) { + irq_data->chip_data = NULL; + free_apic_chip_data(data); goto error; + } } return 0; error: - x86_vector_free_irqs(domain, virq, i + 1); + x86_vector_free_irqs(domain, virq, i); return err; } -- cgit v1.2.3 From 6bde094049bf3648882ff8fdfabd7871f40d3935 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 7 Mar 2018 18:36:43 +0000 Subject: x86/apic/vector: Handle legacy irq data correctly The backport of upstream commit 45d55e7bac40 ("x86/apic/vector: Fix off by one in error path") missed to fixup the legacy interrupt data which is not longer available upstream. Handle legacy irq data correctly by clearing the legacy storage to prevent use after free. Fixes: 7fd133539289 ("x86/apic/vector: Fix off by one in error path") - 4.4.y Fixes: c557481a9491 ("x86/apic/vector: Fix off by one in error path") - 4.9.y Reported-by: Ben Hutchings Signed-off-by: Thomas Gleixner Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/apic/vector.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'arch/x86/kernel/apic/vector.c') diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c index a41e523536a2..592e260ba05b 100644 --- a/arch/x86/kernel/apic/vector.c +++ b/arch/x86/kernel/apic/vector.c @@ -91,8 +91,12 @@ out_data: return NULL; } -static void free_apic_chip_data(struct apic_chip_data *data) +static void free_apic_chip_data(unsigned int virq, struct apic_chip_data *data) { +#ifdef CONFIG_X86_IO_APIC + if (virq < nr_legacy_irqs()) + legacy_irq_data[virq] = NULL; +#endif if (data) { free_cpumask_var(data->domain); free_cpumask_var(data->old_domain); @@ -316,11 +320,7 @@ static void x86_vector_free_irqs(struct irq_domain *domain, apic_data = irq_data->chip_data; irq_domain_reset_irq_data(irq_data); raw_spin_unlock_irqrestore(&vector_lock, flags); - free_apic_chip_data(apic_data); -#ifdef CONFIG_X86_IO_APIC - if (virq + i < nr_legacy_irqs()) - legacy_irq_data[virq + i] = NULL; -#endif + free_apic_chip_data(virq + i, apic_data); } } } @@ -361,7 +361,7 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq, err = assign_irq_vector_policy(virq + i, node, data, info); if (err) { irq_data->chip_data = NULL; - free_apic_chip_data(data); + free_apic_chip_data(virq + i, data); goto error; } } -- cgit v1.2.3