diff options
author | James Morse <james.morse@arm.com> | 2022-04-08 18:22:19 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-15 14:18:36 +0200 |
commit | 00914290958d6f458fe118f2fe2451799f92c0a5 (patch) | |
tree | cac0cfd8d8e4913dd770c6c9e880d38c4231f501 /arch | |
parent | 18e0097daf8c0d7897b2847d06f06b3bf44dd59e (diff) |
KVM: arm64: Check arm64_get_bp_hardening_data() didn't return NULL
Will reports that with CONFIG_EXPERT=y and CONFIG_HARDEN_BRANCH_PREDICTOR=n,
the kernel dereferences a NULL pointer during boot:
[ 2.384444] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[ 2.384461] pstate: 20400085 (nzCv daIf +PAN -UAO)
[ 2.384472] pc : cpu_hyp_reinit+0x114/0x30c
[ 2.384476] lr : cpu_hyp_reinit+0x80/0x30c
[ 2.384529] Call trace:
[ 2.384533] cpu_hyp_reinit+0x114/0x30c
[ 2.384537] _kvm_arch_hardware_enable+0x30/0x54
[ 2.384541] flush_smp_call_function_queue+0xe4/0x154
[ 2.384544] generic_smp_call_function_single_interrupt+0x10/0x18
[ 2.384549] ipi_handler+0x170/0x2b0
[ 2.384555] handle_percpu_devid_fasteoi_ipi+0x120/0x1cc
[ 2.384560] __handle_domain_irq+0x9c/0xf4
[ 2.384563] gic_handle_irq+0x6c/0xe4
[ 2.384566] el1_irq+0xf0/0x1c0
[ 2.384570] arch_cpu_idle+0x28/0x44
[ 2.384574] do_idle+0x100/0x2a8
[ 2.384577] cpu_startup_entry+0x20/0x24
[ 2.384581] secondary_start_kernel+0x1b0/0x1cc
[ 2.384589] Code: b9469d08 7100011f 540003ad 52800208 (f9400108)
[ 2.384600] ---[ end trace 266d08dbf96ff143 ]---
[ 2.385171] Kernel panic - not syncing: Fatal exception in interrupt
In this configuration arm64_get_bp_hardening_data() returns NULL.
Add a check in kvm_get_hyp_vector().
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/linux-arm-kernel/20220408120041.GB27685@willie-the-truck/
Fixes: 26129ea2953b ("KVM: arm64: Add templates for BHB mitigation sequences")
Cc: stable@vger.kernel.org # 5.4.x
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/arm64/include/asm/kvm_mmu.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 78d110667c0c..ffe0aad96b17 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -479,7 +479,8 @@ static inline void *kvm_get_hyp_vector(void) int slot = -1; if ((cpus_have_const_cap(ARM64_HARDEN_BRANCH_PREDICTOR) || - cpus_have_const_cap(ARM64_SPECTRE_BHB)) && data->template_start) { + cpus_have_const_cap(ARM64_SPECTRE_BHB)) && + data && data->template_start) { vect = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs_start)); slot = data->hyp_vectors_slot; } |