• Davidlohr Bueso's avatar
    ipc,msg: drop dst nil validation in copy_msg · 5f2a2d5d
    Davidlohr Bueso authored
    d0edd852 ("ipc: convert invalid scenarios to use WARN_ON") relaxed the
    nil dst parameter check, originally being a full BUG_ON.  However, this
    check seems quite unnecessary when the only purpose is for
    ceckpoint/restore (MSG_COPY flag):
    
    o The copy variable is set initially to nil, apparently as a way of
      ensuring that prepare_copy is previously called.  Which is in fact done,
      unconditionally at the beginning of do_msgrcv.
    
    o There is no concurrency with 'copy' (stack allocated in do_msgrcv).
    
    Furthermore, any errors in 'copy' (and thus prepare_copy/copy_msg) should
    always handled by IS_ERR() family.  Therefore remove this check altogether
    as it can never occur with the current users.
    Signed-off-by: 's avatarDavidlohr Bueso <dbueso@suse.de>
    Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
    Signed-off-by: 's avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: 's avatarLinus Torvalds <torvalds@linux-foundation.org>
    5f2a2d5d
msgutil.c 3.63 KB