bpf: mark a NULL kfunc argument precisegrafted

check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.

Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 42 insertions, 0 deletions

diff --git a/drivers/edac/wq.c b/drivers/edac/wq.c
new file mode 100644
index 000000000..ad3f51662
--- /dev/null
+++ b/drivers/edac/wq.c
@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include "edac_module.h"
+
+static struct workqueue_struct *wq;
+
+bool edac_queue_work(struct delayed_work *work, unsigned long delay)
+{
+	return queue_delayed_work(wq, work, delay);
+}
+EXPORT_SYMBOL_GPL(edac_queue_work);
+
+bool edac_mod_work(struct delayed_work *work, unsigned long delay)
+{
+	return mod_delayed_work(wq, work, delay);
+}
+EXPORT_SYMBOL_GPL(edac_mod_work);
+
+bool edac_stop_work(struct delayed_work *work)
+{
+	bool ret;
+
+	ret = cancel_delayed_work_sync(work);
+	flush_workqueue(wq);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(edac_stop_work);
+
+int edac_workqueue_setup(void)
+{
+	wq = alloc_ordered_workqueue("edac-poller", WQ_MEM_RECLAIM);
+	if (!wq)
+		return -ENODEV;
+	else
+		return 0;
+}
+
+void edac_workqueue_teardown(void)
+{
+	destroy_workqueue(wq);
+	wq = NULL;
+}