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Message-ID: <eca412f9-b642-48c8-f0ba-b02c0b7cefad@suse.cz>
Date:   Mon, 2 Oct 2023 09:11:02 +0200
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Subject: Re: [PATCH v3 2/3] mmap: Fix error paths with dup_anon_vma()
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To:     "Liam R. Howlett" <Liam.Howlett@oracle.com>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Jann Horn <jannh@google.com>,
        Lorenzo Stoakes <lstoakes@gmail.com>,
        Suren Baghdasaryan <surenb@google.com>,
        Matthew Wilcox <willy@infradead.org>, stable@vger.kernel.org
References: <20230929183041.2835469-1-Liam.Howlett@oracle.com>
 <20230929183041.2835469-3-Liam.Howlett@oracle.com>
From:   Vlastimil Babka <vbabka@suse.cz>
In-Reply-To: <20230929183041.2835469-3-Liam.Howlett@oracle.com>
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On 9/29/23 20:30, Liam R. Howlett wrote:
> When the calling function fails after the dup_anon_vma(), the
> duplication of the anon_vma is not being undone.  Add the necessary
> unlink_anon_vma() call to the error paths that are missing them.
> 
> This issue showed up during inspection of the error path in vma_merge()
> for an unrelated vma iterator issue.
> 
> Users may experience increased memory usage, which may be problematic as
> the failure would likely be caused by a low memory situation.
> 
> Fixes: d4af56c5c7c6 ("mm: start tracking VMAs with maple tree")
> Cc: stable@vger.kernel.org
> Cc: Jann Horn <jannh@google.com>
> Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>

Acked-by: Vlastimil Babka <vbabka@suse.cz>