From 33a154a96e71a34a1bcca9f40da343dbbf7b38b4 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 1 Oct 2026 14:52:55 +0000 Subject: selftests/bpf: Test packet range of pointers sharing an id Add tests where two packet pointers share an id and tightening one pointer's umax from its var_off would put it less than their constant distance from the other's umax: with an index & 0x38 capped at 50, the base pointer keeps umax 50, so the pointer 8 bytes further on must keep umax 58, even though its known bits allow at most 56. These refused a valid program or accepted an out-of-bounds access before the fix: - check the advanced copy, load through the base: valid, was refused; - check the base, load the byte at base + 1 through a copy advanced by 8: was accepted; - check base + 4, load 4 bytes at base + 2 through base + 8: reads two bytes past the checked range, was accepted; - the same as the second with data_meta pointers checked against data: was accepted. These pass with and without the fix and cover nearby paths: - subtract an unknown scalar from a checked pointer and load below it (the range is kept across a new id); - reach a load through two paths whose checks cover 8 and 7 bytes after the loaded pointer; the second path must not be pruned by the first; - spill a copy of a pointer, check the pointer, fill the copy and load one byte past the checked range: the load is refused, and the copy has the range of the check. Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- scripts/kconfig/util.c | 121 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 121 insertions(+) create mode 100644 scripts/kconfig/util.c (limited to 'scripts/kconfig/util.c') diff --git a/scripts/kconfig/util.c b/scripts/kconfig/util.c new file mode 100644 index 000000000..0809aa061 --- /dev/null +++ b/scripts/kconfig/util.c @@ -0,0 +1,121 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2002-2005 Roman Zippel + * Copyright (C) 2002-2005 Sam Ravnborg + */ + +#include +#include +#include + +#include +#include +#include +#include "lkc.h" + +/* hash table of all parsed Kconfig files */ +static HASHTABLE_DEFINE(file_hashtable, 1U << 11); + +struct file { + struct hlist_node node; + struct { + const char *name; + int lineno; + } parent; + char name[]; +}; + +static void die_duplicated_include(struct file *file, + const char *parent, int lineno) +{ + fprintf(stderr, + "%s:%d: error: repeated inclusion of %s\n" + "%s:%d: note: location of first inclusion of %s\n", + parent, lineno, file->name, + file->parent.name, file->parent.lineno, file->name); + exit(1); +} + +/* file already present in list? If not add it */ +const char *file_lookup(const char *name, + const char *parent_name, int parent_lineno) +{ + const char *parent = NULL; + struct file *file; + size_t len; + int hash = hash_str(name); + + if (parent_name) + parent = file_lookup(parent_name, NULL, 0); + + hash_for_each_possible(file_hashtable, file, node, hash) + if (!strcmp(name, file->name)) { + if (!parent_name) + return file->name; + die_duplicated_include(file, parent, parent_lineno); + } + + len = strlen(name); + file = xmalloc(sizeof(*file) + len + 1); + memset(file, 0, sizeof(*file)); + memcpy(file->name, name, len); + file->name[len] = '\0'; + file->parent.name = parent; + file->parent.lineno = parent_lineno; + + hash_add(file_hashtable, &file->node, hash); + + str_printf(&autoconf_cmd, "\t%s \\\n", name); + + return file->name; +} + +/* Allocate initial growable string */ +struct gstr str_new(void) +{ + struct gstr gs; + gs.s = xmalloc(sizeof(char) * 64); + gs.len = 64; + gs.max_width = 0; + strcpy(gs.s, "\0"); + return gs; +} + +/* Free storage for growable string */ +void str_free(struct gstr *gs) +{ + free(gs->s); + gs->s = NULL; + gs->len = 0; +} + +/* Append to growable string */ +void str_append(struct gstr *gs, const char *s) +{ + size_t l; + if (s) { + l = strlen(gs->s) + strlen(s) + 1; + if (l > gs->len) { + gs->s = xrealloc(gs->s, l); + gs->len = l; + } + strcat(gs->s, s); + } +} + +/* Append printf formatted string to growable string */ +void str_printf(struct gstr *gs, const char *fmt, ...) +{ + va_list ap; + char s[10000]; /* big enough... */ + va_start(ap, fmt); + vsnprintf(s, sizeof(s), fmt, ap); + str_append(gs, s); + va_end(ap); +} + +/* Retrieve value of growable string */ +char *str_get(const struct gstr *gs) +{ + return gs->s; +} -- cgit v1.3.1