diff options
| author | Lukas Gerlach <lukas.gerlach@cispa.de> | 2026-01-16 10:57:31 +0100 |
|---|---|---|
| committer | Anup Patel <anup@brainfault.org> | 2026-03-06 11:20:30 +0530 |
| commit | 8565617a8599dd17b96b7bf7e1eb19809ac6ae5e (patch) | |
| tree | e292746984e5c13925c3aee325875b9d28cc8187 /arch/riscv | |
| parent | 11439c4635edd669ae435eec308f4ab8a0804808 (diff) | |
| download | lwn-8565617a8599dd17b96b7bf7e1eb19809ac6ae5e.tar.gz lwn-8565617a8599dd17b96b7bf7e1eb19809ac6ae5e.zip | |
KVM: riscv: Fix Spectre-v1 in APLIC interrupt handling
Guests can control IRQ indices via MMIO. Sanitize them with
array_index_nospec() to prevent speculative out-of-bounds access
to the aplic->irqs[] array.
Similar to arm64 commit 41b87599c743 ("KVM: arm/arm64: vgic: fix possible
spectre-v1 in vgic_get_irq()") and x86 commit 8c86405f606c ("KVM: x86:
Protect ioapic_read_indirect() from Spectre-v1/L1TF attacks").
Fixes: 74967aa208e2 ("RISC-V: KVM: Add in-kernel emulation of AIA APLIC")
Signed-off-by: Lukas Gerlach <lukas.gerlach@cispa.de>
Reviewed-by: Nutty Liu <nutty.liu@hotmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260116095731.24555-1-lukas.gerlach@cispa.de
Signed-off-by: Anup Patel <anup@brainfault.org>
Diffstat (limited to 'arch/riscv')
| -rw-r--r-- | arch/riscv/kvm/aia_aplic.c | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/arch/riscv/kvm/aia_aplic.c b/arch/riscv/kvm/aia_aplic.c index d1e50bf5c351..3464f3351df7 100644 --- a/arch/riscv/kvm/aia_aplic.c +++ b/arch/riscv/kvm/aia_aplic.c @@ -10,6 +10,7 @@ #include <linux/irqchip/riscv-aplic.h> #include <linux/kvm_host.h> #include <linux/math.h> +#include <linux/nospec.h> #include <linux/spinlock.h> #include <linux/swab.h> #include <kvm/iodev.h> @@ -45,7 +46,7 @@ static u32 aplic_read_sourcecfg(struct aplic *aplic, u32 irq) if (!irq || aplic->nr_irqs <= irq) return 0; - irqd = &aplic->irqs[irq]; + irqd = &aplic->irqs[array_index_nospec(irq, aplic->nr_irqs)]; raw_spin_lock_irqsave(&irqd->lock, flags); ret = irqd->sourcecfg; @@ -61,7 +62,7 @@ static void aplic_write_sourcecfg(struct aplic *aplic, u32 irq, u32 val) if (!irq || aplic->nr_irqs <= irq) return; - irqd = &aplic->irqs[irq]; + irqd = &aplic->irqs[array_index_nospec(irq, aplic->nr_irqs)]; if (val & APLIC_SOURCECFG_D) val = 0; @@ -81,7 +82,7 @@ static u32 aplic_read_target(struct aplic *aplic, u32 irq) if (!irq || aplic->nr_irqs <= irq) return 0; - irqd = &aplic->irqs[irq]; + irqd = &aplic->irqs[array_index_nospec(irq, aplic->nr_irqs)]; raw_spin_lock_irqsave(&irqd->lock, flags); ret = irqd->target; @@ -97,7 +98,7 @@ static void aplic_write_target(struct aplic *aplic, u32 irq, u32 val) if (!irq || aplic->nr_irqs <= irq) return; - irqd = &aplic->irqs[irq]; + irqd = &aplic->irqs[array_index_nospec(irq, aplic->nr_irqs)]; val &= APLIC_TARGET_EIID_MASK | (APLIC_TARGET_HART_IDX_MASK << APLIC_TARGET_HART_IDX_SHIFT) | @@ -116,7 +117,7 @@ static bool aplic_read_pending(struct aplic *aplic, u32 irq) if (!irq || aplic->nr_irqs <= irq) return false; - irqd = &aplic->irqs[irq]; + irqd = &aplic->irqs[array_index_nospec(irq, aplic->nr_irqs)]; raw_spin_lock_irqsave(&irqd->lock, flags); ret = (irqd->state & APLIC_IRQ_STATE_PENDING) ? true : false; @@ -132,7 +133,7 @@ static void aplic_write_pending(struct aplic *aplic, u32 irq, bool pending) if (!irq || aplic->nr_irqs <= irq) return; - irqd = &aplic->irqs[irq]; + irqd = &aplic->irqs[array_index_nospec(irq, aplic->nr_irqs)]; raw_spin_lock_irqsave(&irqd->lock, flags); @@ -170,7 +171,7 @@ static bool aplic_read_enabled(struct aplic *aplic, u32 irq) if (!irq || aplic->nr_irqs <= irq) return false; - irqd = &aplic->irqs[irq]; + irqd = &aplic->irqs[array_index_nospec(irq, aplic->nr_irqs)]; raw_spin_lock_irqsave(&irqd->lock, flags); ret = (irqd->state & APLIC_IRQ_STATE_ENABLED) ? true : false; @@ -186,7 +187,7 @@ static void aplic_write_enabled(struct aplic *aplic, u32 irq, bool enabled) if (!irq || aplic->nr_irqs <= irq) return; - irqd = &aplic->irqs[irq]; + irqd = &aplic->irqs[array_index_nospec(irq, aplic->nr_irqs)]; raw_spin_lock_irqsave(&irqd->lock, flags); if (enabled) @@ -205,7 +206,7 @@ static bool aplic_read_input(struct aplic *aplic, u32 irq) if (!irq || aplic->nr_irqs <= irq) return false; - irqd = &aplic->irqs[irq]; + irqd = &aplic->irqs[array_index_nospec(irq, aplic->nr_irqs)]; raw_spin_lock_irqsave(&irqd->lock, flags); @@ -254,7 +255,7 @@ static void aplic_update_irq_range(struct kvm *kvm, u32 first, u32 last) for (irq = first; irq <= last; irq++) { if (!irq || aplic->nr_irqs <= irq) continue; - irqd = &aplic->irqs[irq]; + irqd = &aplic->irqs[array_index_nospec(irq, aplic->nr_irqs)]; raw_spin_lock_irqsave(&irqd->lock, flags); @@ -283,7 +284,7 @@ int kvm_riscv_aia_aplic_inject(struct kvm *kvm, u32 source, bool level) if (!aplic || !source || (aplic->nr_irqs <= source)) return -ENODEV; - irqd = &aplic->irqs[source]; + irqd = &aplic->irqs[array_index_nospec(source, aplic->nr_irqs)]; ie = (aplic->domaincfg & APLIC_DOMAINCFG_IE) ? true : false; raw_spin_lock_irqsave(&irqd->lock, flags); |