Re: [PATCH] ipc/shm: Fix order of parameters when calling copy_compat_shmid_to_user

From: Al Viro
Date: Wed Sep 20 2017 - 07:01:13 EST

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...