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/common/md4.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 fs/smb/common/md4.h (limited to 'fs/smb/common/md4.h') diff --git a/fs/smb/common/md4.h b/fs/smb/common/md4.h new file mode 100644 index 000000000..5337becc6 --- /dev/null +++ b/fs/smb/common/md4.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Common values for ARC4 Cipher Algorithm + */ + +#ifndef _CIFS_MD4_H +#define _CIFS_MD4_H + +#include + +#define MD4_DIGEST_SIZE 16 +#define MD4_HMAC_BLOCK_SIZE 64 +#define MD4_BLOCK_WORDS 16 +#define MD4_HASH_WORDS 4 + +struct md4_ctx { + u32 hash[MD4_HASH_WORDS]; + u32 block[MD4_BLOCK_WORDS]; + u64 byte_count; +}; + + +int cifs_md4_init(struct md4_ctx *mctx); +int cifs_md4_update(struct md4_ctx *mctx, const u8 *data, unsigned int len); +int cifs_md4_final(struct md4_ctx *mctx, u8 *out); + +#endif /* _CIFS_MD4_H */ -- cgit v1.3.1