Messages in this thread Patch in this message | | | From | cgel.zte@gmail ... | Subject | [PATCH] Modify the check condition | Date | Sat, 18 Sep 2021 06:52:32 +0000 |
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From: Yang Guang <yang.guang5@zte.com.cn>
The vma may be NULL, and accessing the member of vma like "vma->vm_start" in calling follow_phys may occur segmentation fault. So it should check vma at beginning. If vma is null, it will return. And the if condition won't execute "vm->vm_flags".
Signed-off-by: Yang Guang <yang.guang5@zte.com.cn> --- arch/x86/mm/pat/memtype.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c index 4ba2a3ee4bce..b7108b37b754 100644 --- a/arch/x86/mm/pat/memtype.c +++ b/arch/x86/mm/pat/memtype.c @@ -1089,7 +1089,7 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, resource_size_t paddr; unsigned long prot; - if (vma && !(vma->vm_flags & VM_PAT)) + if (!(vma) || !(vma->vm_flags & VM_PAT)) return; /* free the chunk starting from pfn or the whole chunk */ -- 2.25.1
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