From: Jeremy Cline <jcline@redhat.com>
Date: Sat, 4 Apr 2020 01:14:30 -0400
Subject: libbpf: Initialize *nl_pid so gcc 10 is happy
Patch-mainline: v5.7-rc2
Git-commit: 4734b0fefbbf98f8c119eb8344efa19dac82cd2c
References: bsc#1177028
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 <jcline@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200404051430.698058-1-jcline@redhat.com
Acked-by: Gary Lin <glin@suse.com>
---
tools/lib/bpf/netlink.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/tools/lib/bpf/netlink.c
+++ b/tools/lib/bpf/netlink.c
@@ -142,7 +142,7 @@ static int __bpf_set_link_xdp_fd_replace
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, s
{
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)