Message ID | 20200916173311.30956-21-gvrose8192@gmail.com |
---|---|
State | Changes Requested |
Headers | show |
Series | Add support for Linux kernels up to 5.8.x | expand |
On Wed, Sep 16, 2020 at 10:35 AM Greg Rose <gvrose8192@gmail.com> wrote: > > From: Kees Cook <keescook@chromium.org> > > Upstream commit: > commit 16a556eeb7ed2dc3709fe2c5be76accdfa4901ab > Author: Kees Cook <keescook@chromium.org> > Date: Wed Feb 19 22:23:09 2020 -0800 > > openvswitch: Distribute switch variables for initialization > > Variables declared in a switch statement before any case statements > cannot be automatically initialized with compiler instrumentation (as > they are not part of any execution flow). With GCC's proposed automatic > stack variable initialization feature, this triggers a warning (and they > don't get initialized). Clang's automatic stack variable initialization > (via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also > doesn't initialize such variables[1]. Note that these warnings (or silent > skipping) happen before the dead-store elimination optimization phase, > so even when the automatic initializations are later elided in favor of > direct initializations, the warnings remain. > > To avoid these problems, move such variables into the "case" where > they're used or lift them up into the main function body. > > net/openvswitch/flow_netlink.c: In function ‘validate_set’: > net/openvswitch/flow_netlink.c:2711:29: warning: statement will never be executed [-Wswitch-unreachable] > 2711 | const struct ovs_key_ipv4 *ipv4_key; > | ^~~~~~~~ > > [1] https://bugs.llvm.org/show_bug.cgi?id=44916 > > Signed-off-by: Kees Cook <keescook@chromium.org> > Signed-off-by: David S. Miller <davem@davemloft.net> > > Cc: Kees Cook <keescook@chromium.org> > Signed-off-by: Greg Rose <gvrose8192@gmail.com> > --- Acked-by: Yi-Hung Wei <yihung.wei@gmail.com>
diff --git a/datapath/flow_netlink.c b/datapath/flow_netlink.c index d3fd77106..996041602 100644 --- a/datapath/flow_netlink.c +++ b/datapath/flow_netlink.c @@ -2700,10 +2700,6 @@ static int validate_set(const struct nlattr *a, return -EINVAL; switch (key_type) { - const struct ovs_key_ipv4 *ipv4_key; - const struct ovs_key_ipv6 *ipv6_key; - int err; - case OVS_KEY_ATTR_PRIORITY: case OVS_KEY_ATTR_SKB_MARK: case OVS_KEY_ATTR_CT_MARK: @@ -2715,7 +2711,9 @@ static int validate_set(const struct nlattr *a, return -EINVAL; break; - case OVS_KEY_ATTR_TUNNEL: + case OVS_KEY_ATTR_TUNNEL: { + int err; + #ifndef USE_UPSTREAM_TUNNEL if (eth_p_mpls(eth_type)) return -EINVAL; @@ -2728,8 +2726,10 @@ static int validate_set(const struct nlattr *a, if (err) return err; break; + } + case OVS_KEY_ATTR_IPV4: { + const struct ovs_key_ipv4 *ipv4_key; - case OVS_KEY_ATTR_IPV4: if (eth_type != htons(ETH_P_IP)) return -EINVAL; @@ -2749,8 +2749,10 @@ static int validate_set(const struct nlattr *a, return -EINVAL; } break; + } + case OVS_KEY_ATTR_IPV6: { + const struct ovs_key_ipv6 *ipv6_key; - case OVS_KEY_ATTR_IPV6: if (eth_type != htons(ETH_P_IPV6)) return -EINVAL; @@ -2777,7 +2779,7 @@ static int validate_set(const struct nlattr *a, return -EINVAL; break; - + } case OVS_KEY_ATTR_TCP: if ((eth_type != htons(ETH_P_IP) && eth_type != htons(ETH_P_IPV6)) ||