From: Paolo Abeni pabeni@redhat.com
[ Upstream commit 2cbad989033bff0256675c38f96f5faab852af4b ]
The WARN_ONCE() in bpf_warn_invalid_xdp_action() can be triggered by any bugged program, and even attaching a correct program to a NIC not supporting the given action.
The resulting splat, beyond polluting the logs, fouls automated tools: e.g. a syzkaller reproducers using an XDP program returning an unsupported action will never pass validation.
Replace the WARN_ONCE with a less intrusive pr_warn_once().
Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Acked-by: Toke Høiland-Jørgensen toke@redhat.com Link: https://lore.kernel.org/bpf/016ceec56e4817ebb2a9e35ce794d5c917df572c.1638189... Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/filter.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/net/core/filter.c b/net/core/filter.c index 706c31ae65b01..7fa4283f2a8c0 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -7921,9 +7921,9 @@ void bpf_warn_invalid_xdp_action(u32 act) { const u32 act_max = XDP_REDIRECT;
- WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n", - act > act_max ? "Illegal" : "Driver unsupported", - act); + pr_warn_once("%s XDP return value %u, expect packet loss!\n", + act > act_max ? "Illegal" : "Driver unsupported", + act); } EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);