Commit e0ae7130 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Jakub Kicinski
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xdp: xdp_mem_allocator can be NULL in trace_mem_connect(). 



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: 4a48ef70 ("xdp: Allow registering memory model without rxq reference")
Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: default avatarToke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/YikmmXsffE+QajTB@linutronix.de


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 5cb1ebdb

net/core/xdp.c

+2 −1
Original line number Diff line number Diff line
@@ -357,6 +357,7 @@ int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq, 
	if (IS_ERR(xdp_alloc))

		return PTR_ERR(xdp_alloc);



	if (trace_mem_connect_enabled() && xdp_alloc)

		trace_mem_connect(xdp_alloc, xdp_rxq);

	return 0;

}