From 30623e1ed116bcd1785217d0a98eec643687e091 Mon Sep 17 00:00:00 2001 From: Arthur Kiyanovski Date: Tue, 17 Mar 2020 09:06:41 +0200 Subject: [PATCH] net: ena: avoid memory access violation by validating req_id properly Rx req_id is an index in struct ena_eth_io_rx_cdesc_base. The driver should validate that the Rx req_id it received from the device is in range [0, ring_size -1]. Failure to do so could yield to potential memory access violoation. The validation was mistakenly done when refilling the Rx submission queue and not in Rx completion queue. Fixes: ad974baef2a1 ("net: ena: add support for out of order rx buffers refill") Signed-off-by: Noam Dagan Signed-off-by: Arthur Kiyanovski Signed-off-by: David S. Miller --- drivers/net/ethernet/amazon/ena/ena_netdev.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c index 836fda585391..51333a05c14d 100644 --- a/drivers/net/ethernet/amazon/ena/ena_netdev.c +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c @@ -1018,13 +1018,9 @@ static int ena_refill_rx_bufs(struct ena_ring *rx_ring, u32 num) struct ena_rx_buffer *rx_info; req_id = rx_ring->free_ids[next_to_use]; - rc = validate_rx_req_id(rx_ring, req_id); - if (unlikely(rc < 0)) - break; rx_info = &rx_ring->rx_buffer_info[req_id]; - rc = ena_alloc_rx_page(rx_ring, rx_info, GFP_ATOMIC | __GFP_COMP); if (unlikely(rc < 0)) { @@ -1379,9 +1375,15 @@ static struct sk_buff *ena_rx_skb(struct ena_ring *rx_ring, struct ena_rx_buffer *rx_info; u16 len, req_id, buf = 0; void *va; + int rc; len = ena_bufs[buf].len; req_id = ena_bufs[buf].req_id; + + rc = validate_rx_req_id(rx_ring, req_id); + if (unlikely(rc < 0)) + return NULL; + rx_info = &rx_ring->rx_buffer_info[req_id]; if (unlikely(!rx_info->page)) { @@ -1454,6 +1456,11 @@ static struct sk_buff *ena_rx_skb(struct ena_ring *rx_ring, buf++; len = ena_bufs[buf].len; req_id = ena_bufs[buf].req_id; + + rc = validate_rx_req_id(rx_ring, req_id); + if (unlikely(rc < 0)) + return NULL; + rx_info = &rx_ring->rx_buffer_info[req_id]; } while (1); -- 2.11.0