On 03/05/2018 12:22 PM, Dave Hansen wrote:
On 02/21/2018 09:15 AM, Khalid Aziz wrote:+#define arch_validate_prot(prot, addr) sparc_validate_prot(prot, addr) +static inline int sparc_validate_prot(unsigned long prot, unsigned long addr) +{ + if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM | PROT_ADI)) + return 0; + if (prot & PROT_ADI) { + if (!adi_capable()) + return 0; + + if (addr) { + struct vm_area_struct *vma; + + vma = find_vma(current->mm, addr); + if (vma) { + /* ADI can not be enabled on PFN + * mapped pages + */ + if (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)) + return 0;You don't hold mmap_sem here. How can this work?
Are you suggesting that vma returned by find_vma() could be split or merged underneath me if I do not hold mmap_sem and thus make the flag check invalid? If so, that is a good point.
Thanks, Khalid -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
