Support backports for stable version. There are two places where null
deref could happen before
commit 2c92ca849fcc ("tracing/treewide: Remove second parameter of __assign_str()")
Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@xxxxxxxxxxxxxxxxxxxx/
I've checked +v6.1.82 +v6.6.22 +v6.7.10, +v6.8, +6.9, this version need
to be applied, So, I applied the patch, tested it again, and confirmed
working fine.
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
Cc: stable@xxxxxxxxxxxxxxx # +v6.1.82 +v6.6.22 +v6.7.10, +v6.8, +6.9
Tested-by: Yunseong Kim <yskelg@xxxxxxxxx>
Reviewed-by: Pedro Tammela <pctammela@xxxxxxxxxxxx>
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 | 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;
--
2.45.2
