| Message ID | ea34ed03-23e8-568f-ec50-1f238bc0a350@solarflare.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | sfc: more EF100 fixes | expand |
Edward Cree wrote: > If an ef100_net_open() fails, ef100_net_stop() may be called without > channel->rps_flow_id having been written; thus it may hold the address > freed by a previous ef100_net_stop()'s call to efx_remove_filters(). > This then causes a double-free when efx_remove_filters() is called > again, leading to a panic. > To prevent this, after freeing it, overwrite it with NULL. > > Fixes: a9dc3d5612ce ("sfc_ef100: RX filter table management and related gubbins") > Signed-off-by: Edward Cree <ecree@solarflare.com> > --- > drivers/net/ethernet/sfc/rx_common.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/net/ethernet/sfc/rx_common.c b/drivers/net/ethernet/sfc/rx_common.c > index ef9bca92b0b7..5e29284c89c9 100644 > --- a/drivers/net/ethernet/sfc/rx_common.c > +++ b/drivers/net/ethernet/sfc/rx_common.c > @@ -849,6 +849,7 @@ void efx_remove_filters(struct efx_nic *efx) > efx_for_each_channel(channel, efx) { > cancel_delayed_work_sync(&channel->filter_work); > kfree(channel->rps_flow_id); > + channel->rps_flow_id = NULL; > } > #endif > down_write(&efx->filter_sem); >
Jesse Brandeburg wrote: > Edward Cree wrote: > > > If an ef100_net_open() fails, ef100_net_stop() may be called without > > channel->rps_flow_id having been written; thus it may hold the address > > freed by a previous ef100_net_stop()'s call to efx_remove_filters(). > > This then causes a double-free when efx_remove_filters() is called > > again, leading to a panic. > > To prevent this, after freeing it, overwrite it with NULL. > > > > Fixes: a9dc3d5612ce ("sfc_ef100: RX filter table management and related gubbins") > > Signed-off-by: Edward Cree <ecree@solarflare.com> My mailer messed up my previous reply, but this is what I meant to say: Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
diff --git a/drivers/net/ethernet/sfc/rx_common.c b/drivers/net/ethernet/sfc/rx_common.c index ef9bca92b0b7..5e29284c89c9 100644 --- a/drivers/net/ethernet/sfc/rx_common.c +++ b/drivers/net/ethernet/sfc/rx_common.c @@ -849,6 +849,7 @@ void efx_remove_filters(struct efx_nic *efx) efx_for_each_channel(channel, efx) { cancel_delayed_work_sync(&channel->filter_work); kfree(channel->rps_flow_id); + channel->rps_flow_id = NULL; } #endif down_write(&efx->filter_sem);
If an ef100_net_open() fails, ef100_net_stop() may be called without channel->rps_flow_id having been written; thus it may hold the address freed by a previous ef100_net_stop()'s call to efx_remove_filters(). This then causes a double-free when efx_remove_filters() is called again, leading to a panic. To prevent this, after freeing it, overwrite it with NULL. Fixes: a9dc3d5612ce ("sfc_ef100: RX filter table management and related gubbins") Signed-off-by: Edward Cree <ecree@solarflare.com> --- drivers/net/ethernet/sfc/rx_common.c | 1 + 1 file changed, 1 insertion(+)