From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock Add a sleepable verifier test that loads a graph-node local kptr in an explicit RCU read-side critical section, then passes its node to bpf_rbtree_remove() after the section ends. Before the verifier fix, the stale NON_OWN_REF flag makes the node look like a live borrowed reference and the program is accepted. After the fix, the pointer is demoted without NON_OWN_REF and the graph kfunc argument is rejected. Also exercise a graph kptr loaded while a spin lock provides implicit RCU protection. The pointer must be invalidated when the lock is released, which guards the required ordering between non-owning-reference invalidation and RCU demotion. Update the existing fault-protected load test state description. The post-unlock pointer no longer carries NON_OWN_REF, but remains readable because the load is rewritten to use BPF_PROBE_MEM. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- Documentation/firmware_class/hotplug-script | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) create mode 100644 Documentation/firmware_class/hotplug-script (limited to 'Documentation/firmware_class/hotplug-script') diff --git a/Documentation/firmware_class/hotplug-script b/Documentation/firmware_class/hotplug-script new file mode 100644 index 000000000..8143a950b --- /dev/null +++ b/Documentation/firmware_class/hotplug-script @@ -0,0 +1,17 @@ +#!/bin/sh + +# Simple hotplug script sample: +# +# Both $DEVPATH and $FIRMWARE are already provided in the environment. + +HOTPLUG_FW_DIR=/usr/lib/hotplug/firmware/ + +if [ "$SUBSYSTEM" == "firmware" -a "$ACTION" == "add" ]; then + if [ -f $HOTPLUG_FW_DIR/$FIRMWARE ]; then + echo 1 > /sys/$DEVPATH/loading + cat $HOTPLUG_FW_DIR/$FIRMWARE > /sys/$DEVPATH/data + echo 0 > /sys/$DEVPATH/loading + else + echo -1 > /sys/$DEVPATH/loading + fi +fi -- cgit v1.3.1