diff mbox series

[v2,21/47] iwlwifi: pcie: validate RX descriptor length

Message ID iwlwifi.20201209231352.6378fb435cc0.Ib07485f3dc5999c74b03f21e7a808c50a05e353c@changeid
State New
Headers show
Series iwlwifi: final patches for v5.11 2020-12-09 | expand

Commit Message

Luca Coelho Dec. 9, 2020, 9:16 p.m. UTC 
From: Johannes Berg <johannes.berg@intel.com>

Validate the maximum RX descriptor length against the size
of the buffers we gave the device - if it doesn't fit then
the hardware messed up.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
---
 drivers/net/wireless/intel/iwlwifi/pcie/rx.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
index 94299f259518..ed200f541bfc 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
@@ -1335,6 +1335,13 @@  static void iwl_pcie_rx_handle_rb(struct iwl_trans *trans,
 
 		len = iwl_rx_packet_len(pkt);
 		len += sizeof(u32); /* account for status word */
+
+		offset += ALIGN(len, FH_RSCSR_FRAME_ALIGN);
+
+		/* check that what the device tells us made sense */
+		if (offset > max_len)
+			break;
+
 		trace_iwlwifi_dev_rx(trans->dev, trans, pkt, len);
 		trace_iwlwifi_dev_rx_data(trans->dev, trans, pkt, len);
 
@@ -1392,7 +1399,6 @@  static void iwl_pcie_rx_handle_rb(struct iwl_trans *trans,
 		page_stolen |= rxcb._page_stolen;
 		if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210)
 			break;
-		offset += ALIGN(len, FH_RSCSR_FRAME_ALIGN);
 	}
 
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