From: Sebastian Andrzej Siewior bigeasy@linutronix.de
[ Upstream commit e0ae713023a9d09d6e1b454bdc8e8c1dd32c586e ]
Since the commit mentioned below __xdp_reg_mem_model() can return a NULL pointer. This pointer is dereferenced in trace_mem_connect() which leads to segfault.
The trace points (mem_connect + mem_disconnect) were put in place to pair connect/disconnect using the IDs. The ID is only assigned if __xdp_reg_mem_model() does not return NULL. That connect trace point is of no use if there is no ID.
Skip that connect trace point if xdp_alloc is NULL.
[ Toke Høiland-Jørgensen delivered the reasoning for skipping the trace point ]
Fixes: 4a48ef70b93b8 ("xdp: Allow registering memory model without rxq reference") Signed-off-by: Sebastian Andrzej Siewior bigeasy@linutronix.de Acked-by: Toke Høiland-Jørgensen toke@redhat.com Link: https://lore.kernel.org/r/YikmmXsffE+QajTB@linutronix.de Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/xdp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/core/xdp.c b/net/core/xdp.c index 5ed2e9d5a3191..a3e3d2538a3a8 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -359,7 +359,8 @@ int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq, if (IS_ERR(xdp_alloc)) return PTR_ERR(xdp_alloc);
- trace_mem_connect(xdp_alloc, xdp_rxq); + if (trace_mem_connect_enabled() && xdp_alloc) + trace_mem_connect(xdp_alloc, xdp_rxq); return 0; }