| Message ID | 67956320a8ee663f2582cc75f0e8047d69da5f6a.1737371364.git.geert@linux-m68k.org (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net-next,v2] ipv4: ip_gre: Fix set but not used warning in ipgre_err() if IPv4-only | expand |
On Mon, Jan 20, 2025 at 02:12:36PM +0100, Geert Uytterhoeven wrote: > if CONFIG_NET_IPGRE is enabled, but CONFIG_IPV6 is disabled: > > net/ipv4/ip_gre.c: In function ‘ipgre_err’: > net/ipv4/ip_gre.c:144:22: error: variable ‘data_len’ set but not used [-Werror=unused-but-set-variable] > 144 | unsigned int data_len = 0; > | ^~~~~~~~ > > Fix this by moving all data_len processing inside the IPV6-only section > that uses its result. > > Reported-by: kernel test robot <lkp@intel.com> > Closes: https://lore.kernel.org/oe-kbuild-all/202501121007.2GofXmh5-lkp@intel.com/ > Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> > --- > v2: > - Do not use the ternary operator, > - Target net-next. Thanks Geert, This has been bothering me too. Reviewed-by: Simon Horman <horms@kernel.org>
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index f1f31ebfc7934467..9667f27740258efb 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -141,7 +141,6 @@ static int ipgre_err(struct sk_buff *skb, u32 info, const struct iphdr *iph; const int type = icmp_hdr(skb)->type; const int code = icmp_hdr(skb)->code; - unsigned int data_len = 0; struct ip_tunnel *t; if (tpi->proto == htons(ETH_P_TEB)) @@ -182,7 +181,6 @@ static int ipgre_err(struct sk_buff *skb, u32 info, case ICMP_TIME_EXCEEDED: if (code != ICMP_EXC_TTL) return 0; - data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */ break; case ICMP_REDIRECT: @@ -190,10 +188,16 @@ static int ipgre_err(struct sk_buff *skb, u32 info, } #if IS_ENABLED(CONFIG_IPV6) - if (tpi->proto == htons(ETH_P_IPV6) && - !ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len, - type, data_len)) - return 0; + if (tpi->proto == htons(ETH_P_IPV6)) { + unsigned int data_len = 0; + + if (type == ICMP_TIME_EXCEEDED) + data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */ + + if (!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len, + type, data_len)) + return 0; + } #endif if (t->parms.iph.daddr == 0 ||
if CONFIG_NET_IPGRE is enabled, but CONFIG_IPV6 is disabled: net/ipv4/ip_gre.c: In function ‘ipgre_err’: net/ipv4/ip_gre.c:144:22: error: variable ‘data_len’ set but not used [-Werror=unused-but-set-variable] 144 | unsigned int data_len = 0; | ^~~~~~~~ Fix this by moving all data_len processing inside the IPV6-only section that uses its result. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202501121007.2GofXmh5-lkp@intel.com/ Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> --- v2: - Do not use the ternary operator, - Target net-next. --- net/ipv4/ip_gre.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-)