From 7dc4a6b5ca942a7196e17ecb3827b406cf79bc60 Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Mon, 24 Jul 2017 18:13:19 -0700 Subject: [PATCH] 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 Signed-off-by: Kalle Valo --- drivers/net/wireless/marvell/mwifiex/pcie.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c index 21f2201405d1..f54053e6fb60 100644 --- a/drivers/net/wireless/marvell/mwifiex/pcie.c +++ b/drivers/net/wireless/marvell/mwifiex/pcie.c @@ -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; } /* -- 2.45.2