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 --- sound/firewire/fireface/ff-proc.c | 62 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 sound/firewire/fireface/ff-proc.c (limited to 'sound/firewire/fireface/ff-proc.c') diff --git a/sound/firewire/fireface/ff-proc.c b/sound/firewire/fireface/ff-proc.c new file mode 100644 index 000000000..4aecc8dcb --- /dev/null +++ b/sound/firewire/fireface/ff-proc.c @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ff-proc.c - a part of driver for RME Fireface series + * + * Copyright (c) 2015-2017 Takashi Sakamoto + */ + +#include "./ff.h" + +const char *snd_ff_proc_get_clk_label(enum snd_ff_clock_src src) +{ + static const char *const labels[] = { + "Internal", + "S/PDIF", + "ADAT1", + "ADAT2", + "Word", + "LTC", + }; + + if (src >= ARRAY_SIZE(labels)) + return NULL; + + return labels[src]; +} + +static void proc_dump_status(struct snd_info_entry *entry, + struct snd_info_buffer *buffer) +{ + struct snd_ff *ff = entry->private_data; + + ff->spec->protocol->dump_status(ff, buffer); +} + +static void add_node(struct snd_ff *ff, struct snd_info_entry *root, + const char *name, + void (*op)(struct snd_info_entry *e, + struct snd_info_buffer *b)) +{ + struct snd_info_entry *entry; + + entry = snd_info_create_card_entry(ff->card, name, root); + if (entry) + snd_info_set_text_ops(entry, ff, op); +} + +void snd_ff_proc_init(struct snd_ff *ff) +{ + struct snd_info_entry *root; + + /* + * All nodes are automatically removed at snd_card_disconnect(), + * by following to link list. + */ + root = snd_info_create_card_entry(ff->card, "firewire", + ff->card->proc_root); + if (root == NULL) + return; + root->mode = S_IFDIR | 0555; + + add_node(ff, root, "status", proc_dump_status); +} -- cgit v1.3.1