From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= <toke@redhat.com>
Date: Tue, 14 Apr 2020 16:50:24 +0200
Subject: libbpf: Fix type of old_fd in bpf_xdp_set_link_opts
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Patch-mainline: v5.7-rc2
Git-commit: 49b452c382da2c2d1ccee1265cbb92da905c82f7
References: bsc#1177028

The 'old_fd' parameter used for atomic replacement of XDP programs is
supposed to be an FD, but was left as a u32 from an earlier iteration of
the patch that added it. It was converted to an int when read, so things
worked correctly even with negative values, but better change the
definition to correctly reflect the intention.

Fixes: bd5ca3ef93cd ("libbpf: Add function to set link XDP fd while specifying old program")
Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David Ahern <dsahern@gmail.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200414145025.182163-1-toke@redhat.com
Acked-by: Gary Lin <glin@suse.com>
---
 tools/lib/bpf/libbpf.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -458,7 +458,7 @@ struct xdp_link_info {
 
 struct bpf_xdp_set_link_opts {
 	size_t sz;
-	__u32 old_fd;
+	int old_fd;
 };
 #define bpf_xdp_set_link_opts__last_field old_fd