[PATCH 1/3] softmmu: Assert data in bounds in iotlb_to_section

Richard Henderson posted 3 patches 1 year, 3 months ago
Maintainers: Richard Henderson <richard.henderson@linaro.org>, Paolo Bonzini <pbonzini@redhat.com>, Peter Xu <peterx@redhat.com>, David Hildenbrand <david@redhat.com>, "Philippe Mathieu-Daudé" <philmd@linaro.org>
[PATCH 1/3] softmmu: Assert data in bounds in iotlb_to_section
Posted by Richard Henderson 1 year, 3 months ago
Suggested-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 softmmu/physmem.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/softmmu/physmem.c b/softmmu/physmem.c
index 3df73542e1..7597dc1c39 100644
--- a/softmmu/physmem.c
+++ b/softmmu/physmem.c
@@ -2413,9 +2413,15 @@ MemoryRegionSection *iotlb_to_section(CPUState *cpu,
     int asidx = cpu_asidx_from_attrs(cpu, attrs);
     CPUAddressSpace *cpuas = &cpu->cpu_ases[asidx];
     AddressSpaceDispatch *d = qatomic_rcu_read(&cpuas->memory_dispatch);
-    MemoryRegionSection *sections = d->map.sections;
+    int section_index = index & ~TARGET_PAGE_MASK;
+    MemoryRegionSection *ret;
 
-    return &sections[index & ~TARGET_PAGE_MASK];
+    assert(section_index < d->map.sections_nb);
+    ret = d->map.sections + section_index;
+    assert(ret->mr);
+    assert(ret->mr->ops);
+
+    return ret;
 }
 
 static void io_mem_init(void)
-- 
2.34.1


Re: [PATCH 1/3] softmmu: Assert data in bounds in iotlb_to_section
Posted by Alex Bennée 1 year, 3 months ago
Richard Henderson <richard.henderson@linaro.org> writes:

> Suggested-by: Alex Bennée <alex.bennee@linaro.org>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  softmmu/physmem.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/softmmu/physmem.c b/softmmu/physmem.c
> index 3df73542e1..7597dc1c39 100644
> --- a/softmmu/physmem.c
> +++ b/softmmu/physmem.c
> @@ -2413,9 +2413,15 @@ MemoryRegionSection *iotlb_to_section(CPUState *cpu,
>      int asidx = cpu_asidx_from_attrs(cpu, attrs);
>      CPUAddressSpace *cpuas = &cpu->cpu_ases[asidx];
>      AddressSpaceDispatch *d = qatomic_rcu_read(&cpuas->memory_dispatch);
> -    MemoryRegionSection *sections = d->map.sections;
> +    int section_index = index & ~TARGET_PAGE_MASK;
> +    MemoryRegionSection *ret;

It might be worth a quick comment where section_index comes from because
I was confused initially expecting it to be address like.

>  
> -    return &sections[index & ~TARGET_PAGE_MASK];
> +    assert(section_index < d->map.sections_nb);
> +    ret = d->map.sections + section_index;
> +    assert(ret->mr);
> +    assert(ret->mr->ops);
> +
> +    return ret;
>  }
>  
>  static void io_mem_init(void)

Otherwise:

Acked-by: Alex Bennée <alex.bennee@linaro.org>

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro