From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B38CAC433E1 for ; Tue, 23 Mar 2021 18:26:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D095619C5 for ; Tue, 23 Mar 2021 18:26:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231728AbhCWS0E (ORCPT ); Tue, 23 Mar 2021 14:26:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44026 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231455AbhCWSZe (ORCPT ); Tue, 23 Mar 2021 14:25:34 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A536EC061574 for ; Tue, 23 Mar 2021 11:25:34 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id j19so3473551ybg.5 for ; Tue, 23 Mar 2021 11:25:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=dY7WA+UEN40ndqtDO7RREDL5/0nyCAvFJ0UPO+eomVs=; b=r7X+QE2kE7/WKXlDrA2RA+qriBrJ7O7/Zbw4BWQohT1QckYfsCiullXxdtvOjPSjx2 /QsVEx5udz4PpuhSdakuaUkaQM6DluYT1W36ElHFZKXD3pITIt7fZknCC9jo69V93JIj ObiRX3d2bjEJKgnarX73B6RfhLchUBboImOsICYHDyE1/orAix04zLT5he4TnE+au1Cw kObbIgB76AqOPTjBMa9vLEjK/sK4le2D0vppwlAAb4w0p/eBwZCqGBOStZLx92mdNaBH b9e4pDgWEH+m1BMGDkgKxIycG/f4Zt77bsgAn5oh+fPeQUMjYYYgMAIIx5fiZBPqzgiq 4UIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=dY7WA+UEN40ndqtDO7RREDL5/0nyCAvFJ0UPO+eomVs=; b=mfbjglRtU0Lk7bZxohXUJPLoXvHWSGdAA9+rfNk0GXQgGRUH5q4OLpWb5R2R9P5DeJ 3L5eVUaWafIvz/tL2jvBugLSGT7ghiNdeFd+jv0BAhcnrDJcFRcez2sRmzanTMleDRlY bPkLsZEob4Hbk1jdD8Jnto4/iSmeYRNhziLhtgkfywJrEnnZfxJEqJFT7lKj3UFZXqTA cAbsrYo/nkrX7lmDnvu6YllqX1+XERQJOYr0jiLOkNMVfxboFVcRyP8usccS2i0bXRMO V1/RkWOUJSQvMRXrDuwpznA3rrc6+YhuUci/ps4qwYXOCBq/0pyrL5TyoBuTDVsqFB5x n6RQ== X-Gm-Message-State: AOAM530cR9efFqNF/8NHPJCZcBbTAQv9wCsF7WD9HBFCtnK5UA+3+qde JPv45UQ7IZ8mqMEqM4BnknaNeez/2KUg X-Google-Smtp-Source: ABdhPJy8jbCMWhdnWSi7dX5ifnQwWGCqzH8htG0mfRL0hzsDMRzqT9Ury8PnrGWjrz/VHIAXw+TaGgoArHJZ X-Received: from bg.sfo.corp.google.com ([2620:15c:8:10:b047:e98d:2134:b4dd]) (user=bgeffon job=sendgmr) by 2002:a25:ae9f:: with SMTP id b31mr7241564ybj.160.1616523933889; Tue, 23 Mar 2021 11:25:33 -0700 (PDT) Date: Tue, 23 Mar 2021 11:25:18 -0700 In-Reply-To: <20210323182520.2712101-1-bgeffon@google.com> Message-Id: <20210323182520.2712101-2-bgeffon@google.com> Mime-Version: 1.0 References: <20210303175235.3308220-1-bgeffon@google.com> <20210323182520.2712101-1-bgeffon@google.com> X-Mailer: git-send-email 2.31.0.291.g576ba9dcdaf-goog Subject: [PATCH v5 2/3] Revert "mremap: don't allow MREMAP_DONTUNMAP on special_mappings and aio" From: Brian Geffon To: Andrew Morton Cc: Axel Rasmussen , Lokesh Gidra , Mike Rapoport , Peter Xu , Hugh Dickins , "Michael S . Tsirkin" , Brian Geffon , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andy Lutomirski , Vlastimil Babka , Andrea Arcangeli , Sonny Rao , Minchan Kim , "Kirill A . Shutemov" , Dmitry Safonov , Michael Kerrisk , Alejandro Colomar Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This reverts commit cd544fd1dc9293c6702fab6effa63dac1cc67e99. As discussed in [1] this commit was a no-op because the mapping type was checked in vma_to_resize before move_vma is ever called. This meant that vm_ops->mremap() would never be called on such mappings. Furthermore, we've since expanded support of MREMAP_DONTUNMAP to non-anonymous mappings, and these special mappings are still protected by the existing check of !VM_DONTEXPAND and !VM_PFNMAP which will result in a -EINVAL. 1. https://lkml.org/lkml/2020/12/28/2340 Signed-off-by: Brian Geffon Acked-by: Hugh Dickins --- arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 2 +- fs/aio.c | 5 +---- include/linux/mm.h | 2 +- mm/mmap.c | 6 +----- mm/mremap.c | 2 +- 5 files changed, 5 insertions(+), 12 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c index e916646adc69..0daf2f1cf7a8 100644 --- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c +++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c @@ -1458,7 +1458,7 @@ static int pseudo_lock_dev_release(struct inode *inode, struct file *filp) return 0; } -static int pseudo_lock_dev_mremap(struct vm_area_struct *area, unsigned long flags) +static int pseudo_lock_dev_mremap(struct vm_area_struct *area) { /* Not supported */ return -EINVAL; diff --git a/fs/aio.c b/fs/aio.c index 1f32da13d39e..76ce0cc3ee4e 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -323,16 +323,13 @@ static void aio_free_ring(struct kioctx *ctx) } } -static int aio_ring_mremap(struct vm_area_struct *vma, unsigned long flags) +static int aio_ring_mremap(struct vm_area_struct *vma) { struct file *file = vma->vm_file; struct mm_struct *mm = vma->vm_mm; struct kioctx_table *table; int i, res = -EINVAL; - if (flags & MREMAP_DONTUNMAP) - return -EINVAL; - spin_lock(&mm->ioctx_lock); rcu_read_lock(); table = rcu_dereference(mm->ioctx_table); diff --git a/include/linux/mm.h b/include/linux/mm.h index 64a71bf20536..ecdc6e8dc5af 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -570,7 +570,7 @@ struct vm_operations_struct { void (*close)(struct vm_area_struct * area); /* Called any time before splitting to check if it's allowed */ int (*may_split)(struct vm_area_struct *area, unsigned long addr); - int (*mremap)(struct vm_area_struct *area, unsigned long flags); + int (*mremap)(struct vm_area_struct *area); /* * Called by mprotect() to make driver-specific permission * checks before mprotect() is finalised. The VMA must not diff --git a/mm/mmap.c b/mm/mmap.c index 3f287599a7a3..9d7651e4e1fe 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -3403,14 +3403,10 @@ static const char *special_mapping_name(struct vm_area_struct *vma) return ((struct vm_special_mapping *)vma->vm_private_data)->name; } -static int special_mapping_mremap(struct vm_area_struct *new_vma, - unsigned long flags) +static int special_mapping_mremap(struct vm_area_struct *new_vma) { struct vm_special_mapping *sm = new_vma->vm_private_data; - if (flags & MREMAP_DONTUNMAP) - return -EINVAL; - if (WARN_ON_ONCE(current->mm != new_vma->vm_mm)) return -EFAULT; diff --git a/mm/mremap.c b/mm/mremap.c index db5b8b28c2dd..d22629ff8f3c 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -545,7 +545,7 @@ static unsigned long move_vma(struct vm_area_struct *vma, if (moved_len < old_len) { err = -ENOMEM; } else if (vma->vm_ops && vma->vm_ops->mremap) { - err = vma->vm_ops->mremap(new_vma, flags); + err = vma->vm_ops->mremap(new_vma); } if (unlikely(err)) { -- 2.31.0.291.g576ba9dcdaf-goog From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0A965C433E0 for ; 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s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=dY7WA+UEN40ndqtDO7RREDL5/0nyCAvFJ0UPO+eomVs=; b=hQzJjuaGrGCta71aNxGHNzoLZ4DblTYlFWjHlgfnZI5A7nnKdArnG/s6rHHBon+ipb F/hsQQdDTllusjVapUb3nPgbbRuH518aRAm/CrenC/7C1Q/PCVo9o2NlGwq1JoXhLX81 PbL3ENStMKCGmHWaQ5kvrgJ7AqQBWLc4fARlDA9/fjtF6D2bqlbWR+clUwy6I1DSeFo7 JnNfCX4scw1kv7hnLhJQ9Lx4XxObkcikUWlXTqKILBD9GS/W3drN+AnI6lLt26Qtrh/U du0RdSiowQdRx/o4v2sAeVrBepvBIueqMAgHNckUtXhquYC4TIw6wwE6+OFCaJbA7epN yqRA== X-Gm-Message-State: AOAM531rXFekM6e0UbEmYK6FDePzpSb/32L2WhAna5yghZkW12ctCcma vj5DNHsg11o/h9NDH5+xSmLpJXOmrPaq X-Google-Smtp-Source: ABdhPJy8jbCMWhdnWSi7dX5ifnQwWGCqzH8htG0mfRL0hzsDMRzqT9Ury8PnrGWjrz/VHIAXw+TaGgoArHJZ X-Received: from bg.sfo.corp.google.com ([2620:15c:8:10:b047:e98d:2134:b4dd]) (user=bgeffon job=sendgmr) by 2002:a25:ae9f:: with SMTP id b31mr7241564ybj.160.1616523933889; Tue, 23 Mar 2021 11:25:33 -0700 (PDT) Date: Tue, 23 Mar 2021 11:25:18 -0700 In-Reply-To: <20210323182520.2712101-1-bgeffon@google.com> Message-Id: <20210323182520.2712101-2-bgeffon@google.com> Mime-Version: 1.0 References: <20210303175235.3308220-1-bgeffon@google.com> <20210323182520.2712101-1-bgeffon@google.com> X-Mailer: git-send-email 2.31.0.291.g576ba9dcdaf-goog Subject: [PATCH v5 2/3] Revert "mremap: don't allow MREMAP_DONTUNMAP on special_mappings and aio" From: Brian Geffon To: Andrew Morton Cc: Axel Rasmussen , Lokesh Gidra , Mike Rapoport , Peter Xu , Hugh Dickins , "Michael S . Tsirkin" , Brian Geffon , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andy Lutomirski , Vlastimil Babka , Andrea Arcangeli , Sonny Rao , Minchan Kim , "Kirill A . Shutemov" , Dmitry Safonov , Michael Kerrisk , Alejandro Colomar Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: jik4ktfdygbeazwpcdunpwot63hs9ckh X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 9B2F7C0007E2 Received-SPF: none (flex--bgeffon.bounces.google.com>: No applicable sender policy available) receiver=imf06; identity=mailfrom; envelope-from="<3nTJaYAcKCHQTYWXXgfYggYdW.Ugedafmp-eecnSUc.gjY@flex--bgeffon.bounces.google.com>"; helo=mail-yb1-f201.google.com; client-ip=209.85.219.201 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616523934-439570 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: This reverts commit cd544fd1dc9293c6702fab6effa63dac1cc67e99. As discussed in [1] this commit was a no-op because the mapping type was checked in vma_to_resize before move_vma is ever called. This meant that vm_ops->mremap() would never be called on such mappings. Furthermore, we've since expanded support of MREMAP_DONTUNMAP to non-anonymous mappings, and these special mappings are still protected by the existing check of !VM_DONTEXPAND and !VM_PFNMAP which will result in a -EINVAL. 1. https://lkml.org/lkml/2020/12/28/2340 Signed-off-by: Brian Geffon Acked-by: Hugh Dickins --- arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 2 +- fs/aio.c | 5 +---- include/linux/mm.h | 2 +- mm/mmap.c | 6 +----- mm/mremap.c | 2 +- 5 files changed, 5 insertions(+), 12 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c index e916646adc69..0daf2f1cf7a8 100644 --- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c +++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c @@ -1458,7 +1458,7 @@ static int pseudo_lock_dev_release(struct inode *inode, struct file *filp) return 0; } -static int pseudo_lock_dev_mremap(struct vm_area_struct *area, unsigned long flags) +static int pseudo_lock_dev_mremap(struct vm_area_struct *area) { /* Not supported */ return -EINVAL; diff --git a/fs/aio.c b/fs/aio.c index 1f32da13d39e..76ce0cc3ee4e 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -323,16 +323,13 @@ static void aio_free_ring(struct kioctx *ctx) } } -static int aio_ring_mremap(struct vm_area_struct *vma, unsigned long flags) +static int aio_ring_mremap(struct vm_area_struct *vma) { struct file *file = vma->vm_file; struct mm_struct *mm = vma->vm_mm; struct kioctx_table *table; int i, res = -EINVAL; - if (flags & MREMAP_DONTUNMAP) - return -EINVAL; - spin_lock(&mm->ioctx_lock); rcu_read_lock(); table = rcu_dereference(mm->ioctx_table); diff --git a/include/linux/mm.h b/include/linux/mm.h index 64a71bf20536..ecdc6e8dc5af 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -570,7 +570,7 @@ struct vm_operations_struct { void (*close)(struct vm_area_struct * area); /* Called any time before splitting to check if it's allowed */ int (*may_split)(struct vm_area_struct *area, unsigned long addr); - int (*mremap)(struct vm_area_struct *area, unsigned long flags); + int (*mremap)(struct vm_area_struct *area); /* * Called by mprotect() to make driver-specific permission * checks before mprotect() is finalised. The VMA must not diff --git a/mm/mmap.c b/mm/mmap.c index 3f287599a7a3..9d7651e4e1fe 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -3403,14 +3403,10 @@ static const char *special_mapping_name(struct vm_area_struct *vma) return ((struct vm_special_mapping *)vma->vm_private_data)->name; } -static int special_mapping_mremap(struct vm_area_struct *new_vma, - unsigned long flags) +static int special_mapping_mremap(struct vm_area_struct *new_vma) { struct vm_special_mapping *sm = new_vma->vm_private_data; - if (flags & MREMAP_DONTUNMAP) - return -EINVAL; - if (WARN_ON_ONCE(current->mm != new_vma->vm_mm)) return -EFAULT; diff --git a/mm/mremap.c b/mm/mremap.c index db5b8b28c2dd..d22629ff8f3c 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -545,7 +545,7 @@ static unsigned long move_vma(struct vm_area_struct *vma, if (moved_len < old_len) { err = -ENOMEM; } else if (vma->vm_ops && vma->vm_ops->mremap) { - err = vma->vm_ops->mremap(new_vma, flags); + err = vma->vm_ops->mremap(new_vma); } if (unlikely(err)) { -- 2.31.0.291.g576ba9dcdaf-goog