4.20-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit f4924f24da8c7ef64195096817f3cde324091d97 ]
In sock_setsockopt() (net/core/sock.h), when SO_MARK option is used to change sk_mark, sk_dst_reset(sk) is called. The same should be done in bpf_setsockopt().
Fixes: 8c4b4c7e9ff0 ("bpf: Add setsockopt helper function to bpf") Reported-by: Maciej Żenczykowski maze@google.com Signed-off-by: Peter Oskolkov posk@google.com Acked-by: Martin KaFai Lau kafai@fb.com Reviewed-by: Maciej Żenczykowski maze@google.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/filter.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/net/core/filter.c b/net/core/filter.c index fa9452406f214..e176b335ddc09 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3948,7 +3948,10 @@ BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock, sk->sk_rcvlowat = val ? : 1; break; case SO_MARK: - sk->sk_mark = val; + if (sk->sk_mark != val) { + sk->sk_mark = val; + sk_dst_reset(sk); + } break; default: ret = -EINVAL;