Re: [PATCH] spi: core: Fix Oops in spi_pump_messages error path

From: Geert Uytterhoeven
Date: Mon Feb 17 2014 - 13:02:20 EST


On Mon, Feb 17, 2014 at 6:20 PM, Maxime Ripard
<maxime.ripard@xxxxxxxxxxxxxxxxxx> wrote:
> When the generic implementation of the transfer_one_message callback was called
> by the spi_pump_messages function, if that transfer was to fail, the
> spi_finalize_current_message was called twice, once in
> spi_transfer_one_message, and one in spi_pump_messages.
>
> This was causing a null pointer dereference in the second call, because the
> first one set the ->cur_msg field to NULL.
>
> Since the SPI framework expect the transfer_one_message callback to call
> spi_finalize_current_message, we can remove it from spi_pump_messages, together
> with any dereference of the ->cur_msg pointer.
>
> Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx

Already fixed in v3.14-rc3 in 1f802f8249a0da536877842c43c7204064c4de8b
("spi: Fix crash with double message finalisation on error handling").

There's no need to inform stable, as the problem was introduced in v3.14-rc1.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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