qemu: Avoid crash in qemuDomainCheckCPU with unknown host CPU

[PATCH] qemu: Avoid crash in qemuDomainCheckCPU with unknown host CPU

Posted by Jiri Denemark 11 months, 3 weeks ago

When we don't have any information about host CPU (for example when
running on an aarch64 host), the virQEMUCapsGetHostModel would return
NULL.

Fixes: https://gitlab.com/libvirt/libvirt/-/issues/747
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 src/qemu/qemu_domain.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index cf05dca55a..df1ed0223d 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -11430,6 +11430,7 @@ qemuDomainCheckCPU(virArch arch,
     /* Force compat check if the CPU model is not found in qemuCaps or
      * we don't have host CPU data from QEMU */
     if (!cpu->model ||
+        !hypervisorCPU ||
         hypervisorCPU->fallback != VIR_CPU_FALLBACK_FORBID ||
         virQEMUCapsGetCPUBlockers(qemuCaps, virtType,
                                   cpu->model, &blockers) < 0)
-- 
2.48.1

Re: [PATCH] qemu: Avoid crash in qemuDomainCheckCPU with unknown host CPU

Posted by Michal Prívozník 11 months, 3 weeks ago

On 2/18/25 11:49, Jiri Denemark wrote:
> When we don't have any information about host CPU (for example when
> running on an aarch64 host), the virQEMUCapsGetHostModel would return
> NULL.
> 
> Fixes: https://gitlab.com/libvirt/libvirt/-/issues/747
> Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

Please also mention:

Fixes: f928eb5fc80ca0ed7277f2513b63aed36c09d275

> ---
>  src/qemu/qemu_domain.c | 1 +
>  1 file changed, 1 insertion(+)

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

Michal

Re: [PATCH] qemu: Avoid crash in qemuDomainCheckCPU with unknown host CPU

Posted by Jaroslav Suchanek 11 months, 3 weeks ago

On Tue, Feb 18, 2025 at 11:49:53AM +0100, Jiri Denemark wrote:
> When we don't have any information about host CPU (for example when
> running on an aarch64 host), the virQEMUCapsGetHostModel would return
> NULL.

Tested-by: Jaroslav Suchanek <jsuchane@redhat.com>

> 
> Fixes: https://gitlab.com/libvirt/libvirt/-/issues/747
> Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
> ---
>  src/qemu/qemu_domain.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
> index cf05dca55a..df1ed0223d 100644
> --- a/src/qemu/qemu_domain.c
> +++ b/src/qemu/qemu_domain.c
> @@ -11430,6 +11430,7 @@ qemuDomainCheckCPU(virArch arch,
>      /* Force compat check if the CPU model is not found in qemuCaps or
>       * we don't have host CPU data from QEMU */
>      if (!cpu->model ||
> +        !hypervisorCPU ||
>          hypervisorCPU->fallback != VIR_CPU_FALLBACK_FORBID ||
>          virQEMUCapsGetCPUBlockers(qemuCaps, virtType,
>                                    cpu->model, &blockers) < 0)
> -- 
> 2.48.1
> 

-- 
J.