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Date: Wed, 20 Sep 2017 12:01:07 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Will Deacon <will.deacon@arm.com>
Cc: linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] ipc/shm: Fix order of parameters when calling
 copy_compat_shmid_to_user
Message-ID: <20170920110107.GC32076@ZenIV.linux.org.uk>
References: <1505753258-19470-1-git-send-email-will.deacon@arm.com>
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On Mon, Sep 18, 2017 at 05:47:38PM +0100, Will Deacon wrote:
> Commit 553f770ef71b ("ipc: move compat shmctl to native") moved the
> compat IPC syscall handling into ipc/shm.c and refactored the struct
> accessors in the process. Unfortunately, the call to
> copy_compat_shmid_to_user when handling a compat {IPC,SHM}_STAT command
> gets the arguments the wrong way round, passing a kernel stack address
> as the user buffer (destination) and the user buffer as the kernel stack
> address (source).
> 
> This patch fixes the parameter ordering so the buffers are accessed
> correctly.

ACK, will push to Linus tonight...