On Thu, 2020-12-03 at 11:30 +0000, Catalin Marinas wrote: > On Fri, Nov 27, 2020 at 01:07:38PM +0800, Miles Chen wrote: > > Cc: Will Deacon <will.deacon@xxxxxxx> > > That should be will@xxxxxxxxxx. ok, I will fix it and submit v3 > > > diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c > > index 217aa2705d5d..92b277388f05 100644 > > --- a/fs/proc/task_mmu.c > > +++ b/fs/proc/task_mmu.c > > @@ -1599,11 +1599,15 @@ static ssize_t pagemap_read(struct file *file, char __user *buf, > > > > src = *ppos; > > svpfn = src / PM_ENTRY_BYTES; > > - start_vaddr = svpfn << PAGE_SHIFT; > > end_vaddr = mm->task_size; > > > > /* watch out for wraparound */ > > - if (svpfn > mm->task_size >> PAGE_SHIFT) > > + start_vaddr = end_vaddr; > > + if (svpfn < (ULONG_MAX >> PAGE_SHIFT)) > > Does this need to be strict less-than? I think a less-than or equal > would work better. Thanks, I will fix it and submit v3. > > > + start_vaddr = untagged_addr(svpfn << PAGE_SHIFT); > > + > > + /* Ensure the address is inside the task */ > > + if (start_vaddr > mm->task_size) > > start_vaddr = end_vaddr; > > Otherwise the logic looks fine to me. With the above: > > Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>
