From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1FB043398B for ; Fri, 13 Dec 2024 02:29:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734056990; cv=none; b=bQP78t2xe+Zdi5cbkCAQpDneAOcD5hQEBUxR7kuiSx8WsMZcbb2hsiRNugaYCXPZ4m+Nky4jrQ6n6pumZTqfwd7rU1IV4dZJboH4KDNtkFrKmP8gNGtk8rJh708Y82cs2C8gAtegNewqrt/GUNBpltTUfTtV+PH+jpbeDD46emY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734056990; c=relaxed/simple; bh=hMtdqqLUgAcf5AmbgpiuhpRJk/HgvWJQJt+erNliOok=; h=Date:To:From:Subject:Message-Id; b=ZSoDdE/wsHH8PYNa6heT0IdXYyx5hDPgLp2p+ozzysUOWFQnL+5yYvyr1HcvlNsiP+Et72Z5DDijDZPOfPe5Uot7KX90E7EOe5F0iVc309FKRdgXWzEDyF2ZdD7DPxYLtJcD3wQUr5uAFftNiLlN5nqII4HOE/4ga5GwERMWj1c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=zYLJ/Lhe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="zYLJ/Lhe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 930BBC4CECE; Fri, 13 Dec 2024 02:29:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1734056989; bh=hMtdqqLUgAcf5AmbgpiuhpRJk/HgvWJQJt+erNliOok=; h=Date:To:From:Subject:From; b=zYLJ/LhemIYW7tFfp+8yfw5LRsBxTepDv/H33frcn/4guZVdB+4ocpxOZt4+aMfLE XGv2Ni4RupGJir6PBbr+z6Eb/g6hBvS0EQDMHJD4MZmnnBeaLh9lv8Aq8XLWNHJOsm pj2ZYcWTa6KNuZd6ne2XvBZo37ewq5PH8vswpm1k= Date: Thu, 12 Dec 2024 18:29:49 -0800 To: mm-commits@vger.kernel.org,vbabka@suse.cz,Liam.Howlett@Oracle.com,jannh@google.com,lorenzo.stoakes@oracle.com,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-assert-mmap-write-lock-held-on-do_mmap-mmap_region.patch added to mm-unstable branch Message-Id: <20241213022949.930BBC4CECE@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm: assert mmap write lock held on do_mmap(), mmap_region() has been added to the -mm mm-unstable branch. Its filename is mm-assert-mmap-write-lock-held-on-do_mmap-mmap_region.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-assert-mmap-write-lock-held-on-do_mmap-mmap_region.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Lorenzo Stoakes Subject: mm: assert mmap write lock held on do_mmap(), mmap_region() Date: Thu, 12 Dec 2024 11:48:41 +0000 Both of these functions can be invoked outside of mm, so it is probably a good idea to assert that the required lock is held. Will only have an impact if CONFIG_DEBUG_VM is set, otherwise this amounts to no change at all. Link: https://lkml.kernel.org/r/20241212114841.55185-1-lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Cc: Jann Horn Cc: Liam R. Howlett Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- mm/mmap.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/mm/mmap.c~mm-assert-mmap-write-lock-held-on-do_mmap-mmap_region +++ a/mm/mmap.c @@ -291,6 +291,8 @@ unsigned long do_mmap(struct file *file, *populate = 0; + mmap_assert_write_locked(mm); + if (!len) return -EINVAL; @@ -1023,6 +1025,8 @@ unsigned long mmap_region(struct file *f unsigned long ret; bool writable_file_mapping = false; + mmap_assert_write_locked(current->mm); + /* Check to see if MDWE is applicable. */ if (map_deny_write_exec(vm_flags, vm_flags)) return -EACCES; _ Patches currently in -mm which might be from lorenzo.stoakes@oracle.com are docs-mm-add-vma-locks-documentation.patch mm-reinstate-ability-to-map-write-sealed-memfd-mappings-read-only.patch selftests-memfd-add-test-for-mapping-write-sealed-memfd-read-only.patch mm-correctly-reference-merged-vma.patch fork-avoid-inappropriate-uprobe-access-to-invalid-mm.patch mm-vma-move-brk-internals-to-mm-vmac.patch mm-vma-move-brk-internals-to-mm-vmac-fix.patch mm-vma-move-unmapped_area-internals-to-mm-vmac.patch mm-abstract-get_arg_page-stack-expansion-and-mmap-read-lock.patch mm-vma-move-stack-expansion-logic-to-mm-vmac.patch mm-vma-move-__vm_munmap-to-mm-vmac.patch selftests-mm-add-fork-cow-guard-page-test.patch mm-enforce-__must_check-on-vma-merge-and-split.patch mm-perform-all-memfd-seal-checks-in-a-single-place.patch mm-perform-all-memfd-seal-checks-in-a-single-place-fix.patch maintainers-update-memory-mapping-section.patch mm-assert-mmap-write-lock-held-on-do_mmap-mmap_region.patch