From e1993df1c756bc491127e3e89ffc5c9c045b31de Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 5 May 2017 15:30:23 -0700 Subject: [PATCH] bna: ethtool: Avoid reading past end of buffer [ Upstream commit 4dc69c1c1fff2f587f8e737e70b4a4e7565a5c94 ] Using memcpy() from a string that is shorter than the length copied means the destination buffer is being filled with arbitrary data from the kernel rodata segment. Instead, use strncpy() which will fill the trailing bytes with zeros. This was found with the future CONFIG_FORTIFY_SOURCE feature. Cc: Daniel Micay Signed-off-by: Kees Cook Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/brocade/bna/bnad_ethtool.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/brocade/bna/bnad_ethtool.c b/drivers/net/ethernet/brocade/bna/bnad_ethtool.c index 0e4fdc3dd729..18672ad773fb 100644 --- a/drivers/net/ethernet/brocade/bna/bnad_ethtool.c +++ b/drivers/net/ethernet/brocade/bna/bnad_ethtool.c @@ -556,8 +556,8 @@ bnad_get_strings(struct net_device *netdev, u32 stringset, u8 *string) for (i = 0; i < BNAD_ETHTOOL_STATS_NUM; i++) { BUG_ON(!(strlen(bnad_net_stats_strings[i]) < ETH_GSTRING_LEN)); - memcpy(string, bnad_net_stats_strings[i], - ETH_GSTRING_LEN); + strncpy(string, bnad_net_stats_strings[i], + ETH_GSTRING_LEN); string += ETH_GSTRING_LEN; } bmap = bna_tx_rid_mask(&bnad->bna);