Re: Re: [PATCH net] [v2] sfc: fix a double-free bug in efx_probe_filters

From: alexious
Date: Mon Dec 25 2023 - 06:29:16 EST



> On Fri, Dec 22, 2023 at 11:49:52PM +0800, Zhipeng Lu wrote:
> > In efx_probe_filters, the channel->rps_flow_id is freed in a
> > efx_for_each_channel marco when success equals to 0.
> > However, after the following call chain:
> >
> > ef100_net_open
> > |-> efx_probe_filters
> > |-> ef100_net_stop
> > |-> efx_remove_filters
> >
> > The channel->rps_flow_id is freed again in the efx_for_each_channel of
> > efx_remove_filters, triggering a double-free bug.
> > ---
>
> Everything below the line above (---) will be omitted from the commit
> message when the patch is applied.
>
> > Changelog:
> >
> > v2: Correct the call-chain description in commit message and change
> > patch subject.
> >
> > Fixes: a9dc3d5612ce ("sfc_ef100: RX filter table management and related gubbins")
> > Signed-off-by: Zhipeng Lu <alexious@xxxxxxxxxx>
> > Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
> > Reviewed-by: Edward Cree <ecree.xilinx@xxxxxxxxx>
>
> Hi Zhipeng Lu,
>
> I think that your Signed-off-by should go last when you post a patch.
>
> And the Changelog should go below the (first set of) scissors (---).
>
> > ---
> > drivers/net/ethernet/sfc/rx_common.c | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
>
> With the above in mind, I think you want something like:
>
> In efx_probe_filters, the channel->rps_flow_id is freed in a
> efx_for_each_channel marco when success equals to 0.
> However, after the following call chain:
>
> ef100_net_open
> |-> efx_probe_filters
> |-> ef100_net_stop
> |-> efx_remove_filters
>
> The channel->rps_flow_id is freed again in the efx_for_each_channel of
> efx_remove_filters, triggering a double-free bug.
>
> Fixes: a9dc3d5612ce ("sfc_ef100: RX filter table management and related gubbins")
> Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
> Reviewed-by: Edward Cree <ecree.xilinx@xxxxxxxxx>
> Signed-off-by: Zhipeng Lu <alexious@xxxxxxxxxx>
> ---
> Changelog:
>
> v2: Correct the call-chain description in commit message and change
> patch subject.
> ---
> drivers/net/ethernet/sfc/rx_common.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> --
> pw-bot: changes-requested

Thank you for your detailed revision and correction!
I'll send this patch again with your correction.