From a97df7f5cd4798d96a67458d1a708aca6518d439 Mon Sep 17 00:00:00 2001 From: Rahul Rameshbabu Date: Tue, 14 Nov 2023 13:58:45 -0800 Subject: [PATCH] net/mlx5e: Check return value of snprintf writing to fw_version buffer [ Upstream commit 41e63c2baa11dc2aa71df5dd27a5bd87d11b6bbb ] Treat the operation as an error case when the return value is equivalent to the size of the name buffer. Failed to write null terminator to the name buffer, making the string malformed and should not be used. Provide a string with only the firmware version when forming the string with the board id fails. Without check, will trigger -Wformat-truncation with W=1. drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c: In function 'mlx5e_ethtool_get_drvinfo': drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c:49:31: warning: '%.16s' directive output may be truncated writing up to 16 bytes into a region of size between 13 and 22 [-Wformat-truncation=] 49 | "%d.%d.%04d (%.16s)", | ^~~~~ drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c:48:9: note: 'snprintf' output between 12 and 37 bytes into a destination of size 32 48 | snprintf(drvinfo->fw_version, sizeof(drvinfo->fw_version), | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 49 | "%d.%d.%04d (%.16s)", | ~~~~~~~~~~~~~~~~~~~~~ 50 | fw_rev_maj(mdev), fw_rev_min(mdev), fw_rev_sub(mdev), | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 51 | mdev->board_id); | ~~~~~~~~~~~~~~~ Fixes: 84e11edb71de ("net/mlx5e: Show board id in ethtool driver information") Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6d4ab2e97dcfbcd748ae71761a9d8e5e41cc732c Signed-off-by: Rahul Rameshbabu Reviewed-by: Dragos Tatulea Signed-off-by: Saeed Mahameed Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c index dff0243..7c66bd7 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c @@ -43,12 +43,17 @@ void mlx5e_ethtool_get_drvinfo(struct mlx5e_priv *priv, struct ethtool_drvinfo *drvinfo) { struct mlx5_core_dev *mdev = priv->mdev; + int count; strscpy(drvinfo->driver, KBUILD_MODNAME, sizeof(drvinfo->driver)); - 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); + 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)) + snprintf(drvinfo->fw_version, sizeof(drvinfo->fw_version), + "%d.%d.%04d", fw_rev_maj(mdev), + fw_rev_min(mdev), fw_rev_sub(mdev)); + strscpy(drvinfo->bus_info, dev_name(mdev->device), sizeof(drvinfo->bus_info)); } -- 2.7.4