This is a note to let you know that I've just added the patch titled
xdp: xdp_mem_allocator can be NULL in trace_mem_connect().
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
xdp-xdp_mem_allocator-can-be-null-in-trace_mem_conne.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit da98b03bf70e200143f86b1f18a48fd68368eccc
Author: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Date: Wed Mar 9 23:13:45 2022 +0100
xdp: xdp_mem_allocator can be NULL in trace_mem_connect().
[ 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@xxxxxxxxxxxxx>
Acked-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
Link: https://lore.kernel.org/r/YikmmXsffE+QajTB@xxxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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;
}
