Hi Greg,
On 7/3/24 7:40 오후, Greg Kroah-Hartman wrote:
> 5.10-stable review patch. If anyone has any objections, please let me know.
>
> ------------------
>
> From: Yunseong Kim <yskelg@xxxxxxxxx>
>
> [ Upstream commit bab4923132feb3e439ae45962979c5d9d5c7c1f1 ]
>
> In the TRACE_EVENT(qdisc_reset) NULL dereference occurred from
>
> qdisc->dev_queue->dev <NULL> ->name
>
> This situation simulated from bunch of veths and Bluetooth disconnection
> and reconnection.
>
> During qdisc initialization, qdisc was being set to noop_queue.
> In veth_init_queue, the initial tx_num was reduced back to one,
> causing the qdisc reset to be called with noop, which led to the kernel
> panic.
> Fixes: 51270d573a8d ("tracing/net_sched: Fix tracepoints that save qdisc_dev() as a string")
> Link: https://lore.kernel.org/lkml/20240229143432.273b4871@xxxxxxxxxxxxxxxxxx/t/
> Cc: netdev@xxxxxxxxxxxxxxx
> Tested-by: Yunseong Kim <yskelg@xxxxxxxxx>
> Signed-off-by: Yunseong Kim <yskelg@xxxxxxxxx>
> Signed-off-by: Yeoreum Yun <yeoreum.yun@xxxxxxx>
> Link: https://lore.kernel.org/r/20240624173320.24945-4-yskelg@xxxxxxxxx
> Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
> include/trace/events/qdisc.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/trace/events/qdisc.h b/include/trace/events/qdisc.h
> index a50df41634c58..f661d3d7c410a 100644
> --- a/include/trace/events/qdisc.h
> +++ b/include/trace/events/qdisc.h
> @@ -53,7 +53,7 @@ TRACE_EVENT(qdisc_reset,
> TP_ARGS(q),
>
> TP_STRUCT__entry(
> - __string( dev, qdisc_dev(q)->name )
> + __string( dev, qdisc_dev(q) ? qdisc_dev(q)->name : "(null)" )
> __string( kind, q->ops->id )
> __field( u32, parent )
> __field( u32, handle )
Since that code changed in +v5.10.213, +v5.15.152, +v6.1.82 +v6.6.22
+v6.7.10, +v6.8, +6.9 and the stable is in an intermediate state.
commit 2c92ca849fcc ("tracing/treewide: Remove second parameter of
__assign_str()")
Link:
https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@xxxxxxxxxxxxxxxxxxxx/
I had to fix some other part for the stable branch backporting.
So, I submit another patch. Please check out.
Link:
https://lore.kernel.org/stable/20240702180146.5126-2-yskelg@xxxxxxxxx/T/#u
---
include/trace/events/qdisc.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/trace/events/qdisc.h b/include/trace/events/qdisc.h
index 1f4258308b96..061fd4960303 100644
--- a/include/trace/events/qdisc.h
+++ b/include/trace/events/qdisc.h
@@ -81,14 +81,14 @@ TRACE_EVENT(qdisc_reset,
TP_ARGS(q),
TP_STRUCT__entry(
- __string( dev, qdisc_dev(q)->name )
+ __string( dev, qdisc_dev(q) ? qdisc_dev(q)->name : "(null)" )
__string( kind, q->ops->id )
__field( u32, parent )
__field( u32, handle )
),
TP_fast_assign(
- __assign_str(dev, qdisc_dev(q)->name);
+ __assign_str(dev, qdisc_dev(q) ? qdisc_dev(q)->name : "(null)");
__assign_str(kind, q->ops->id);
__entry->parent = q->parent;
__entry->handle = q->handle;
--
