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dkim=pass header.d=google.com header.s=20210112 header.b=ei9P+Bd8; spf=pass (imf18.hostedemail.com: domain of sethjenkins@google.com designates 209.85.218.47 as permitted sender) smtp.mailfrom=sethjenkins@google.com; dmarc=pass (policy=reject) header.from=google.com X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: EC8701C001B X-Rspam-User: X-Stat-Signature: czzcnzpf5zqekjgc67f3t5pwp5ssu16g X-HE-Tag: 1664917569-445169 X-Bogosity: Ham, tests=bogofilter, spamicity=0.017148, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: I concur, mm-stable looks fine to me as well. Jann and I conversed today and the tentative decision since this isn't considered a high-priority security bug is to wait for maple tree to merge into Linus's branch before submitting this patch to stable. On Tue, Oct 4, 2022 at 2:46 PM Andrew Morton wrote: > > On Mon, 3 Oct 2022 18:45:31 -0400 FirstName LastName wrote: > > > From: Seth Jenkins > > > > Commit 258f669e7e88 ("mm: /proc/pid/smaps_rollup: convert to single value > > seq_file") introduced a null-deref if there are no vma's in the task in > > show_smaps_rollup. > > > > --- a/fs/proc/task_mmu.c > > +++ b/fs/proc/task_mmu.c > > @@ -969,7 +969,7 @@ static int show_smaps_rollup(struct seq_file *m, void *v) > > vma = vma->vm_next; > > } > > > > - show_vma_header_prefix(m, priv->mm->mmap->vm_start, > > + show_vma_header_prefix(m, priv->mm->mmap ? priv->mm->mmap->vm_start : 0, > > last_vma_end, 0, 0, 0, 0); > > seq_pad(m, ' '); > > seq_puts(m, "[rollup]\n"); > > The current mm tree is very different here. In fact the bug might not > exist any more. Please take a look at the mm-stable branch at > git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm? > > If no fixes are needed in mm-stable then I guess the process is to > propose this patch to the stable tree maintainers. >