From: Kees Cook Date: Fri, 5 May 2017 22:30:23 +0000 (-0700) Subject: bna: ethtool: Avoid reading past end of buffer X-Git-Tag: Ubuntu-5.2.0-15.16~6899^2~21 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=4dc69c1c1fff2f587f8e737e70b4a4e7565a5c94;p=mirror_ubuntu-eoan-kernel.git bna: ethtool: Avoid reading past end of buffer 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 --- diff --git a/drivers/net/ethernet/brocade/bna/bnad_ethtool.c b/drivers/net/ethernet/brocade/bna/bnad_ethtool.c index 286593922139..31032de5843b 100644 --- a/drivers/net/ethernet/brocade/bna/bnad_ethtool.c +++ b/drivers/net/ethernet/brocade/bna/bnad_ethtool.c @@ -547,8 +547,8 @@ 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);