Messages in this thread | | | From | "Huang\, Ying" <> | Subject | Re: linux-next: not-present page at swap_vma_readahead() | Date | Wed, 15 Apr 2020 10:01:53 +0800 |
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Qian Cai <cai@lca.pw> writes:
>> On Apr 14, 2020, at 10:32 AM, Qian Cai <cai@lca.pw> wrote: >> >> Fuzzers are unhappy. Thoughts? > > This is rather to reproduce. All the traces so far are from copy_from_user() to trigger a page fault, > and then it dereferences a bad pte in swap_vma_readahead(), > > for (i = 0, pte = ra_info.ptes; i < ra_info.nr_pte; > i++, pte++) { > pentry = *pte; <— crashed here. > if (pte_none(pentry))
Is it possible to bisect this?
Because the crash point is identified, it may be helpful to collect and analyze the status of the faulting page table and readahead ptes. But I am not familiar with the ARM64 architecture. So I cannot help much here.
Best Regards, Huang, Ying
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