mwifiex: pcie: don't allow cmd buffer reuse after reset

In rogue cases (due to other bugs) it's possible we try to process an
old command response *after* resetting the device. This could trigger a
double-free (or the SKB can get reallocated elsewhere...causing other
memory corruptions) in mwifiex_pcie_process_cmd_complete().

For safety (and symmetry) let's always NULL out the command buffer as we
free it up. We're already doing this for the command response buffer.

Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
This commit is contained in:
Brian Norris 2017-07-24 18:13:19 -07:00 committed by Kalle Valo
parent 4b1f5a0d2e
commit 7dc4a6b5ca

View File

@ -1043,12 +1043,14 @@ static int mwifiex_pcie_delete_cmdrsp_buf(struct mwifiex_adapter *adapter)
mwifiex_unmap_pci_memory(adapter, card->cmdrsp_buf,
PCI_DMA_FROMDEVICE);
dev_kfree_skb_any(card->cmdrsp_buf);
card->cmdrsp_buf = NULL;
}
if (card && card->cmd_buf) {
mwifiex_unmap_pci_memory(adapter, card->cmd_buf,
PCI_DMA_TODEVICE);
dev_kfree_skb_any(card->cmd_buf);
card->cmd_buf = NULL;
}
return 0;
}
@ -2934,7 +2936,6 @@ static void mwifiex_pcie_free_buffers(struct mwifiex_adapter *adapter)
mwifiex_pcie_delete_evtbd_ring(adapter);
mwifiex_pcie_delete_rxbd_ring(adapter);
mwifiex_pcie_delete_txbd_ring(adapter);
card->cmdrsp_buf = NULL;
}
/*