From 70cc064e043b78797f5d09d9337e5208513c03de Mon Sep 17 00:00:00 2001 From: Shyam Sundar S K Date: Tue, 10 May 2022 20:14:50 +0800 Subject: [PATCH] net: amd-xgbe: Fix skb data length underflow stable inclusion from stable-v5.10.97 commit 4d3fcfe8464838b3920bc2b939d888e0b792934e bugzilla: https://gitee.com/openeuler/kernel/issues/I55O0O Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4d3fcfe8464838b3920bc2b939d888e0b792934e -------------------------------- commit 5aac9108a180fc06e28d4e7fb00247ce603b72ee upstream. There will be BUG_ON() triggered in include/linux/skbuff.h leading to intermittent kernel panic, when the skb length underflow is detected. Fix this by dropping the packet if such length underflows are seen because of inconsistencies in the hardware descriptors. Fixes: 622c36f143fc ("amd-xgbe: Fix jumbo MTU processing on newer hardware") Suggested-by: Tom Lendacky Signed-off-by: Shyam Sundar S K Acked-by: Tom Lendacky Link: https://lore.kernel.org/r/20220127092003.2812745-1-Shyam-sundar.S-k@amd.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman Signed-off-by: Yu Liao Reviewed-by: Wei Li Signed-off-by: Zheng Zengkai --- drivers/net/ethernet/amd/xgbe/xgbe-drv.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c index 66e71fa50687..a816b30bca04 100644 --- a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c +++ b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c @@ -2559,6 +2559,14 @@ static int xgbe_rx_poll(struct xgbe_channel *channel, int budget) buf2_len = xgbe_rx_buf2_len(rdata, packet, len); len += buf2_len; + if (buf2_len > rdata->rx.buf.dma_len) { + /* Hardware inconsistency within the descriptors + * that has resulted in a length underflow. + */ + error = 1; + goto skip_data; + } + if (!skb) { skb = xgbe_create_skb(pdata, napi, rdata, buf1_len); @@ -2588,8 +2596,10 @@ static int xgbe_rx_poll(struct xgbe_channel *channel, int budget) if (!last || context_next) goto read_again; - if (!skb) + if (!skb || error) { + dev_kfree_skb(skb); goto next_packet; + } /* Be sure we don't exceed the configured MTU */ max_len = netdev->mtu + ETH_HLEN; -- GitLab