From 4734b0fefbbf98f8c119eb8344efa19dac82cd2c Mon Sep 17 00:00:00 2001 From: Jeremy Cline Date: Sat, 4 Apr 2020 01:14:30 -0400 Subject: [PATCH] libbpf: Initialize *nl_pid so gcc 10 is happy Builds of Fedora's kernel-tools package started to fail with "may be used uninitialized" warnings for nl_pid in bpf_set_link_xdp_fd() and bpf_get_link_xdp_info() on the s390 architecture. Although libbpf_netlink_open() always returns a negative number when it does not set *nl_pid, the compiler does not determine this and thus believes the variable might be used uninitialized. Assuage gcc's fears by explicitly initializing nl_pid. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1807781 Signed-off-by: Jeremy Cline Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200404051430.698058-1-jcline@redhat.com --- tools/lib/bpf/netlink.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/lib/bpf/netlink.c b/tools/lib/bpf/netlink.c index 18b5319..9a146941 100644 --- a/tools/lib/bpf/netlink.c +++ b/tools/lib/bpf/netlink.c @@ -142,7 +142,7 @@ static int __bpf_set_link_xdp_fd_replace(int ifindex, int fd, int old_fd, struct ifinfomsg ifinfo; char attrbuf[64]; } req; - __u32 nl_pid; + __u32 nl_pid = 0; sock = libbpf_netlink_open(&nl_pid); if (sock < 0) @@ -288,7 +288,7 @@ int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info, { struct xdp_id_md xdp_id = {}; int sock, ret; - __u32 nl_pid; + __u32 nl_pid = 0; __u32 mask; if (flags & ~XDP_FLAGS_MASK || !info_size) -- 2.7.4