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/soc/codecs/adau-utils.c | 60 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 sound/soc/codecs/adau-utils.c (limited to 'sound/soc/codecs/adau-utils.c') diff --git a/sound/soc/codecs/adau-utils.c b/sound/soc/codecs/adau-utils.c new file mode 100644 index 000000000..836940f2a --- /dev/null +++ b/sound/soc/codecs/adau-utils.c @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Shared helper functions for devices from the ADAU family + * + * Copyright 2011-2016 Analog Devices Inc. + * Author: Lars-Peter Clausen + */ + +#include +#include +#include + +#include "adau-utils.h" + +int adau_calc_pll_cfg(unsigned int freq_in, unsigned int freq_out, + uint8_t regs[5]) +{ + unsigned int r, n, m, i, j; + unsigned int div; + + if (!freq_out) { + r = 0; + n = 0; + m = 0; + div = 0; + } else { + if (freq_out % freq_in != 0) { + div = DIV_ROUND_UP(freq_in, 13500000); + freq_in /= div; + r = freq_out / freq_in; + i = freq_out % freq_in; + j = gcd(i, freq_in); + n = i / j; + m = freq_in / j; + div--; + } else { + r = freq_out / freq_in; + n = 0; + m = 0; + div = 0; + } + if (n > 0xffff || m > 0xffff || div > 3 || r > 8 || r < 2) + return -EINVAL; + } + + regs[0] = m >> 8; + regs[1] = m & 0xff; + regs[2] = n >> 8; + regs[3] = n & 0xff; + regs[4] = (r << 3) | (div << 1); + if (m != 0) + regs[4] |= 1; /* Fractional mode */ + + return 0; +} +EXPORT_SYMBOL_GPL(adau_calc_pll_cfg); + +MODULE_DESCRIPTION("ASoC ADAU audio CODECs shared helper functions"); +MODULE_AUTHOR("Lars-Peter Clausen "); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1