2022-02-01 10:17:38

by Luca Coelho

[permalink] [raw]
Subject: [PATCH 04/12] iwlwifi: pcie: make sure iwl_rx_packet_payload_len() will not underflow

From: Andrei Otcheretianski <[email protected]>

If the device is malfunctioning and reports too short rx descriptor
length, iwl_rx_packet_payload_len() will underflow, eventually resulting
in accessing memory out of bounds and other bad things. Prevent this.

Signed-off-by: Andrei Otcheretianski <[email protected]>
Signed-off-by: Luca Coelho <[email protected]>
---
drivers/net/wireless/intel/iwlwifi/pcie/rx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
index bda98c2eb0ad..e4016c97d5ab 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
@@ -1317,7 +1317,7 @@ static void iwl_pcie_rx_handle_rb(struct iwl_trans *trans,
offset += ALIGN(len, FH_RSCSR_FRAME_ALIGN);

/* check that what the device tells us made sense */
- if (offset > max_len)
+ if (len < sizeof(*pkt) || offset > max_len)
break;

trace_iwlwifi_dev_rx(trans->dev, trans, pkt, len);
--
2.34.1