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 --- drivers/bcma/scan.h | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 drivers/bcma/scan.h (limited to 'drivers/bcma/scan.h') diff --git a/drivers/bcma/scan.h b/drivers/bcma/scan.h new file mode 100644 index 000000000..e53079a3d --- /dev/null +++ b/drivers/bcma/scan.h @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef BCMA_SCAN_H_ +#define BCMA_SCAN_H_ + +#define BCMA_ADDR_BASE 0x18000000 +#define BCMA_WRAP_BASE 0x18100000 + +#define SCAN_ER_VALID 0x00000001 +#define SCAN_ER_TAGX 0x00000006 /* we have to ignore 0x8 bit when checking tag for SCAN_ER_TAG_ADDR */ +#define SCAN_ER_TAG 0x0000000E +#define SCAN_ER_TAG_CI 0x00000000 +#define SCAN_ER_TAG_MP 0x00000002 +#define SCAN_ER_TAG_ADDR 0x00000004 +#define SCAN_ER_TAG_END 0x0000000E +#define SCAN_ER_BAD 0xFFFFFFFF + +#define SCAN_CIA_CLASS 0x000000F0 +#define SCAN_CIA_CLASS_SHIFT 4 +#define SCAN_CIA_ID 0x000FFF00 +#define SCAN_CIA_ID_SHIFT 8 +#define SCAN_CIA_MANUF 0xFFF00000 +#define SCAN_CIA_MANUF_SHIFT 20 + +#define SCAN_CIB_NMP 0x000001F0 +#define SCAN_CIB_NMP_SHIFT 4 +#define SCAN_CIB_NSP 0x00003E00 +#define SCAN_CIB_NSP_SHIFT 9 +#define SCAN_CIB_NMW 0x0007C000 +#define SCAN_CIB_NMW_SHIFT 14 +#define SCAN_CIB_NSW 0x00F80000 +#define SCAN_CIB_NSW_SHIFT 19 +#define SCAN_CIB_REV 0xFF000000 +#define SCAN_CIB_REV_SHIFT 24 + +#define SCAN_ADDR_AG32 0x00000008 +#define SCAN_ADDR_SZ 0x00000030 +#define SCAN_ADDR_SZ_SHIFT 4 +#define SCAN_ADDR_SZ_4K 0x00000000 +#define SCAN_ADDR_SZ_8K 0x00000010 +#define SCAN_ADDR_SZ_16K 0x00000020 +#define SCAN_ADDR_SZ_SZD 0x00000030 +#define SCAN_ADDR_TYPE 0x000000C0 +#define SCAN_ADDR_TYPE_SLAVE 0x00000000 +#define SCAN_ADDR_TYPE_BRIDGE 0x00000040 +#define SCAN_ADDR_TYPE_SWRAP 0x00000080 +#define SCAN_ADDR_TYPE_MWRAP 0x000000C0 +#define SCAN_ADDR_PORT 0x00000F00 +#define SCAN_ADDR_PORT_SHIFT 8 +#define SCAN_ADDR_ADDR 0xFFFFF000 + +#define SCAN_ADDR_SZ_BASE 0x00001000 /* 4KB */ + +#define SCAN_SIZE_SZ_ALIGN 0x00000FFF +#define SCAN_SIZE_SZ 0xFFFFF000 +#define SCAN_SIZE_SG32 0x00000008 + +#endif /* BCMA_SCAN_H_ */ -- cgit v1.3.1