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 --- include/uapi/fwctl/pds.h | 62 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 include/uapi/fwctl/pds.h (limited to 'include/uapi/fwctl/pds.h') diff --git a/include/uapi/fwctl/pds.h b/include/uapi/fwctl/pds.h new file mode 100644 index 000000000..66be32411 --- /dev/null +++ b/include/uapi/fwctl/pds.h @@ -0,0 +1,62 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* Copyright(c) Advanced Micro Devices, Inc */ + +/* + * fwctl interface info for pds_fwctl + */ + +#ifndef _UAPI_FWCTL_PDS_H_ +#define _UAPI_FWCTL_PDS_H_ + +#include + +/** + * struct fwctl_info_pds + * @uctx_caps: bitmap of firmware capabilities + * + * Return basic information about the FW interface available. + */ +struct fwctl_info_pds { + __u32 uctx_caps; +}; + +/** + * enum pds_fwctl_capabilities + * @PDS_FWCTL_QUERY_CAP: firmware can be queried for information + * @PDS_FWCTL_SEND_CAP: firmware can be sent commands + */ +enum pds_fwctl_capabilities { + PDS_FWCTL_QUERY_CAP = 0, + PDS_FWCTL_SEND_CAP, +}; + +/** + * struct fwctl_rpc_pds + * @in.op: requested operation code + * @in.ep: firmware endpoint to operate on + * @in.rsvd: reserved + * @in.len: length of payload data + * @in.payload: address of payload buffer + * @in: rpc in parameters + * @out.retval: operation result value + * @out.rsvd: reserved + * @out.len: length of result data buffer + * @out.payload: address of payload data buffer + * @out: rpc out parameters + */ +struct fwctl_rpc_pds { + struct { + __u32 op; + __u32 ep; + __u32 rsvd; + __u32 len; + __aligned_u64 payload; + } in; + struct { + __u32 retval; + __u32 rsvd[2]; + __u32 len; + __aligned_u64 payload; + } out; +}; +#endif /* _UAPI_FWCTL_PDS_H_ */ -- cgit v1.3.1