From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:36740 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753088AbdLDIsR (ORCPT ); Mon, 4 Dec 2017 03:48:17 -0500 Subject: Patch "device-dax: implement ->split() to catch invalid munmap attempts" has been added to the 4.14-stable tree To: dan.j.williams@intel.com Cc: , From: Date: Mon, 04 Dec 2017 09:48:21 +0100 Message-ID: <15123773016363@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled device-dax: implement ->split() to catch invalid munmap attempts to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: device-dax-implement-split-to-catch-invalid-munmap-attempts.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 9702cffdbf2129516db679e4467db81e1cd287da Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Wed, 29 Nov 2017 16:10:32 -0800 Subject: device-dax: implement ->split() to catch invalid munmap attempts From: Dan Williams commit 9702cffdbf2129516db679e4467db81e1cd287da upstream. Similar to how device-dax enforces that the 'address', 'offset', and 'len' parameters to mmap() be aligned to the device's fundamental alignment, the same constraints apply to munmap(). Implement ->split() to fail munmap calls that violate the alignment constraint. Otherwise, we later fail VM_BUG_ON checks in the unmap_page_range() path with crash signatures of the form: vma ffff8800b60c8a88 start 00007f88c0000000 end 00007f88c0e00000 next (null) prev (null) mm ffff8800b61150c0 prot 8000000000000027 anon_vma (null) vm_ops ffffffffa0091240 pgoff 0 file ffff8800b638ef80 private_data (null) flags: 0x380000fb(read|write|shared|mayread|maywrite|mayexec|mayshare|softdirty|mixedmap|hugepage) ------------[ cut here ]------------ kernel BUG at mm/huge_memory.c:2014! [..] RIP: 0010:__split_huge_pud+0x12a/0x180 [..] Call Trace: unmap_page_range+0x245/0xa40 ? __vma_adjust+0x301/0x990 unmap_vmas+0x4c/0xa0 unmap_region+0xae/0x120 ? __vma_rb_erase+0x11a/0x230 do_munmap+0x276/0x410 vm_munmap+0x6a/0xa0 SyS_munmap+0x1d/0x30 Link: http://lkml.kernel.org/r/151130418681.4029.7118245855057952010.stgit@dwillia2-desk3.amr.corp.intel.com Fixes: dee410792419 ("/dev/dax, core: file operations and dax-mmap") Signed-off-by: Dan Williams Reported-by: Jeff Moyer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/dax/device.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -427,9 +427,21 @@ static int dev_dax_fault(struct vm_fault return dev_dax_huge_fault(vmf, PE_SIZE_PTE); } +static int dev_dax_split(struct vm_area_struct *vma, unsigned long addr) +{ + struct file *filp = vma->vm_file; + struct dev_dax *dev_dax = filp->private_data; + struct dax_region *dax_region = dev_dax->region; + + if (!IS_ALIGNED(addr, dax_region->align)) + return -EINVAL; + return 0; +} + static const struct vm_operations_struct dax_vm_ops = { .fault = dev_dax_fault, .huge_fault = dev_dax_huge_fault, + .split = dev_dax_split, }; static int dax_mmap(struct file *filp, struct vm_area_struct *vma) Patches currently in stable-queue which might be from dan.j.williams@intel.com are queue-4.14/mm-hugetlbfs-introduce-split-to-vm_operations_struct.patch queue-4.14/ib-core-disable-memory-registration-of-filesystem-dax-vmas.patch queue-4.14/mm-introduce-get_user_pages_longterm.patch queue-4.14/mm-fail-get_vaddr_frames-for-filesystem-dax-mappings.patch queue-4.14/device-dax-implement-split-to-catch-invalid-munmap-attempts.patch queue-4.14/v4l2-disable-filesystem-dax-mapping-support.patch queue-4.14/mm-fix-device-dax-pud-write-faults-triggered-by-get_user_pages.patch queue-4.14/mm-madvise.c-fix-madvise-infinite-loop-under-special-circumstances.patch