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 --- fs/smb/client/compress.h | 50 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 fs/smb/client/compress.h (limited to 'fs/smb/client/compress.h') diff --git a/fs/smb/client/compress.h b/fs/smb/client/compress.h new file mode 100644 index 000000000..e08e6d339 --- /dev/null +++ b/fs/smb/client/compress.h @@ -0,0 +1,50 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2024, SUSE LLC + * + * Authors: Enzo Matsumiya + * + * This file implements I/O compression support for SMB2 messages (SMB 3.1.1 only). + * See compress/ for implementation details of each algorithm. + * + * References: + * MS-SMB2 "3.1.4.4 Compressing the Message" - for compression details + * MS-SMB2 "3.1.5.3 Decompressing the Chained Message" - for decompression details + * MS-XCA - for details of the supported algorithms + */ +#ifndef _SMB_COMPRESS_H +#define _SMB_COMPRESS_H + +#include +#include +#include "../common/smb2pdu.h" +#include "../common/compress/compress.h" +#include "cifsglob.h" + +/* sizeof(smb2_compression_hdr) - sizeof(OriginalPayloadSize) */ +#define SMB_COMPRESS_HDR_LEN 16 +/* sizeof(smb2_compression_payload_hdr) - sizeof(OriginalPayloadSize) */ +#define SMB_COMPRESS_PAYLOAD_HDR_LEN 8 +#define SMB_COMPRESS_MIN_LEN PAGE_SIZE + +#ifdef CONFIG_CIFS_COMPRESSION +typedef int (*compress_send_fn)(struct TCP_Server_Info *, int, struct smb_rqst *); + + +int smb_compress(struct TCP_Server_Info *server, struct smb_rqst *rq, + compress_send_fn send_fn); +bool should_compress(const struct cifs_tcon *tcon, const struct smb_rqst *rq); + +#else /* !CONFIG_CIFS_COMPRESSION */ +static inline int smb_compress(void *unused1, void *unused2, void *unused3) +{ + return -EOPNOTSUPP; +} + +static inline bool should_compress(void *unused1, void *unused2) +{ + return false; +} + +#endif /* !CONFIG_CIFS_COMPRESSION */ +#endif /* _SMB_COMPRESS_H */ -- cgit v1.3.1