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/unicode/utf8n.h | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 83 insertions(+) create mode 100644 fs/unicode/utf8n.h (limited to 'fs/unicode/utf8n.h') diff --git a/fs/unicode/utf8n.h b/fs/unicode/utf8n.h new file mode 100644 index 000000000..fc703aa4b --- /dev/null +++ b/fs/unicode/utf8n.h @@ -0,0 +1,83 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2014 SGI. + * All rights reserved. + */ + +#ifndef UTF8NORM_H +#define UTF8NORM_H + +#include +#include +#include +#include +#include + +int utf8version_is_supported(const struct unicode_map *um, unsigned int version); + +/* + * Determine the length of the normalized from of the string, + * excluding any terminating NULL byte. + * Returns 0 if only ignorable code points are present. + * Returns -1 if the input is not valid UTF-8. + */ +ssize_t utf8nlen(const struct unicode_map *um, enum utf8_normalization n, + const char *s, size_t len); + +/* Needed in struct utf8cursor below. */ +#define UTF8HANGULLEAF (12) + +/* + * Cursor structure used by the normalizer. + */ +struct utf8cursor { + const struct unicode_map *um; + enum utf8_normalization n; + const char *s; + const char *p; + const char *ss; + const char *sp; + unsigned int len; + unsigned int slen; + short int ccc; + short int nccc; + unsigned char hangul[UTF8HANGULLEAF]; +}; + +/* + * Initialize a utf8cursor to normalize a string. + * Returns 0 on success. + * Returns -1 on failure. + */ +int utf8ncursor(struct utf8cursor *u8c, const struct unicode_map *um, + enum utf8_normalization n, const char *s, size_t len); + +/* + * Get the next byte in the normalization. + * Returns a value > 0 && < 256 on success. + * Returns 0 when the end of the normalization is reached. + * Returns -1 if the string being normalized is not valid UTF-8. + */ +extern int utf8byte(struct utf8cursor *u8c); + +struct utf8data { + unsigned int maxage; + unsigned int offset; +}; + +struct utf8data_table { + const unsigned int *utf8agetab; + int utf8agetab_size; + + const struct utf8data *utf8nfdicfdata; + int utf8nfdicfdata_size; + + const struct utf8data *utf8nfdidata; + int utf8nfdidata_size; + + const unsigned char *utf8data; +}; + +extern const struct utf8data_table utf8_data_table; + +#endif /* UTF8NORM_H */ -- cgit v1.3.1