With gcc-5 or higher on x86, we can get a bogus warning in the dvb-net code: drivers/media/dvb-core/dvb_net.c: In function ‘dvb_net_ule’: arch/x86/include/asm/string_32.h:77:14: error: ‘dest_addr’ may be used uninitialized in this function [-Werror=maybe-uninitialized] drivers/media/dvb-core/dvb_net.c:633:8: note: ‘dest_addr’ was declared here The problem here is that gcc doesn't track all of the conditions to prove it can't end up copying uninitialized data. This changes the logic around so we zero out the destination address earlier when we determine that it is not set here. This allows the compiler to figure it out. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- v2: fix typo pointed out by Jarod Wilson <jarod@xxxxxxxxxx> drivers/media/dvb-core/dvb_net.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/drivers/media/dvb-core/dvb_net.c b/drivers/media/dvb-core/dvb_net.c index 088914c4623f..c32156426463 100644 --- a/drivers/media/dvb-core/dvb_net.c +++ b/drivers/media/dvb-core/dvb_net.c @@ -688,6 +688,9 @@ static void dvb_net_ule( struct net_device *dev, const u8 *buf, size_t buf_len ) ETH_ALEN); skb_pull(priv->ule_skb, ETH_ALEN); } + } else { + /* otherwise use zero destination address */ + eth_zero_addr(dest_addr); } /* Handle ULE Extension Headers. */ @@ -715,13 +718,8 @@ static void dvb_net_ule( struct net_device *dev, const u8 *buf, size_t buf_len ) if (!priv->ule_bridged) { skb_push(priv->ule_skb, ETH_HLEN); ethh = (struct ethhdr *)priv->ule_skb->data; - if (!priv->ule_dbit) { - /* dest_addr buffer is only valid if priv->ule_dbit == 0 */ - memcpy(ethh->h_dest, dest_addr, ETH_ALEN); - eth_zero_addr(ethh->h_source); - } - else /* zeroize source and dest */ - memset( ethh, 0, ETH_ALEN*2 ); + memcpy(ethh->h_dest, dest_addr, ETH_ALEN); + eth_zero_addr(ethh->h_source); ethh->h_proto = htons(priv->ule_sndu_type); } -- 2.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html