From 952446adc20154df089374066e4c32cde840245d Mon Sep 17 00:00:00 2001 From: Rahul Rameshbabu Date: Tue, 21 Nov 2023 15:00:21 -0800 Subject: [PATCH] net/mlx5e: Correct snprintf truncation handling for fw_version buffer [ Upstream commit ad436b9c1270c40554e274f067f1b78fcc06a004 ] snprintf returns the length of the formatted string, excluding the trailing null, without accounting for truncation. This means that is the return value is greater than or equal to the size parameter, the fw_version string was truncated. Reported-by: David Laight Closes: https://lore.kernel.org/netdev/81cae734ee1b4cde9b380a9a31006c1a@AcuMS.aculab.com/ Link: https://docs.kernel.org/core-api/kernel-api.html#c.snprintf Fixes: 41e63c2baa11 ("net/mlx5e: Check return value of snprintf writing to fw_version buffer") Signed-off-by: Rahul Rameshbabu Reviewed-by: Simon Horman Signed-off-by: Saeed Mahameed Signed-off-by: Sasha Levin --- drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c index 7c66bd7..38263d5 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c @@ -49,7 +49,7 @@ void mlx5e_ethtool_get_drvinfo(struct mlx5e_priv *priv, count = snprintf(drvinfo->fw_version, sizeof(drvinfo->fw_version), "%d.%d.%04d (%.16s)", fw_rev_maj(mdev), fw_rev_min(mdev), fw_rev_sub(mdev), mdev->board_id); - if (count == sizeof(drvinfo->fw_version)) + if (count >= sizeof(drvinfo->fw_version)) snprintf(drvinfo->fw_version, sizeof(drvinfo->fw_version), "%d.%d.%04d", fw_rev_maj(mdev), fw_rev_min(mdev), fw_rev_sub(mdev)); -- 2.7.4