Merge tag 'hardening-v6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull hardening updates from Kees Cook:
 "As has become normal, changes are scattered around the tree (either
  explicitly maintainer Acked or for trivial stuff that went ignored):

   - Carve out the new CONFIG_LIST_HARDENED as a more focused subset of
     CONFIG_DEBUG_LIST (Marco Elver)

   - Fix kallsyms lookup failure under Clang LTO (Yonghong Song)

   - Clarify documentation for CONFIG_UBSAN_TRAP (Jann Horn)

   - Flexible array member conversion not carried in other tree (Gustavo
     A. R. Silva)

   - Various strlcpy() and strncpy() removals not carried in other trees
     (Azeem Shaikh, Justin Stitt)

   - Convert nsproxy.count to refcount_t (Elena Reshetova)

   - Add handful of __counted_by annotations not carried in other trees,
     as well as an LKDTM test

   - Fix build failure with gcc-plugins on GCC 14+

   - Fix selftests to respect SKIP for signal-delivery tests

   - Fix CFI warning for paravirt callback prototype

   - Clarify documentation for seq_show_option_n() usage"

* tag 'hardening-v6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (23 commits)
  LoadPin: Annotate struct dm_verity_loadpin_trusted_root_digest with __counted_by
  kallsyms: Change func signature for cleanup_symbol_name()
  kallsyms: Fix kallsyms_selftest failure
  nsproxy: Convert nsproxy.count to refcount_t
  integrity: Annotate struct ima_rule_opt_list with __counted_by
  lkdtm: Add FAM_BOUNDS test for __counted_by
  Compiler Attributes: counted_by: Adjust name and identifier expansion
  um: refactor deprecated strncpy to memcpy
  um: vector: refactor deprecated strncpy
  alpha: Replace one-element array with flexible-array member
  hardening: Move BUG_ON_DATA_CORRUPTION to hardening options
  list: Introduce CONFIG_LIST_HARDENED
  list_debug: Introduce inline wrappers for debug checks
  compiler_types: Introduce the Clang __preserve_most function attribute
  gcc-plugins: Rename last_stmt() for GCC 14+
  selftests/harness: Actually report SKIP for signal tests
  x86/paravirt: Fix tlb_remove_table function callback prototype warning
  EISA: Replace all non-returning strlcpy with strscpy
  perf: Replace strlcpy with strscpy
  um: Remove strlcpy declaration
  ...

4 files changed, 17 insertions, 43 deletions

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 78ae7b6f90fd..2554f5fc70dc 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8249,7 +8249,7 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
 	unsigned int size;
 
 	memset(comm, 0, sizeof(comm));
-	strlcpy(comm, comm_event->task->comm, sizeof(comm));
+	strscpy(comm, comm_event->task->comm, sizeof(comm));
 	size = ALIGN(strlen(comm)+1, sizeof(u64));
 
 	comm_event->comm = comm;
@@ -8704,7 +8704,7 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
 	}
 
 cpy_name:
-	strlcpy(tmp, name, sizeof(tmp));
+	strscpy(tmp, name, sizeof(tmp));
 	name = tmp;
 got_name:
 	/*
@@ -9128,7 +9128,7 @@ void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister,
 	    ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN)
 		goto err;
 
-	strlcpy(name, sym, KSYM_NAME_LEN);
+	strscpy(name, sym, KSYM_NAME_LEN);
 	name_len = strlen(name) + 1;
 	while (!IS_ALIGNED(name_len, sizeof(u64)))
 		name[name_len++] = '\0';
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 016d997131d4..18edd57b5fe8 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -163,12 +163,12 @@ unsigned long kallsyms_sym_address(int idx)
 	return kallsyms_relative_base - 1 - kallsyms_offsets[idx];
 }
 
-static bool cleanup_symbol_name(char *s)
+static void cleanup_symbol_name(char *s)
 {
 	char *res;
 
 	if (!IS_ENABLED(CONFIG_LTO_CLANG))
-		return false;
+		return;
 
 	/*
 	 * LLVM appends various suffixes for local functions and variables that
@@ -178,26 +178,21 @@ static bool cleanup_symbol_name(char *s)
 	 * - foo.llvm.[0-9a-f]+
 	 */
 	res = strstr(s, ".llvm.");
-	if (res) {
+	if (res)
 		*res = '\0';
-		return true;
-	}
 
-	return false;
+	return;
 }
 
 static int compare_symbol_name(const char *name, char *namebuf)
 {
-	int ret;
-
-	ret = strcmp(name, namebuf);
-	if (!ret)
-		return ret;
-
-	if (cleanup_symbol_name(namebuf) && !strcmp(name, namebuf))
-		return 0;
-
-	return ret;
+	/* The kallsyms_seqs_of_names is sorted based on names after
+	 * cleanup_symbol_name() (see scripts/kallsyms.c) if clang lto is enabled.
+	 * To ensure correct bisection in kallsyms_lookup_names(), do
+	 * cleanup_symbol_name(namebuf) before comparing name and namebuf.
+	 */
+	cleanup_symbol_name(namebuf);
+	return strcmp(name, namebuf);
 }
 
 static unsigned int get_symbol_seq(int index)
diff --git a/kernel/kallsyms_selftest.c b/kernel/kallsyms_selftest.c
index a2e3745d15c4..e05ddc33a752 100644
--- a/kernel/kallsyms_selftest.c
+++ b/kernel/kallsyms_selftest.c
@@ -196,7 +196,7 @@ static bool match_cleanup_name(const char *s, const char *name)
 	if (!IS_ENABLED(CONFIG_LTO_CLANG))
 		return false;
 
-	p = strchr(s, '.');
+	p = strstr(s, ".llvm.");
 	if (!p)
 		return false;
 
@@ -344,27 +344,6 @@ static int test_kallsyms_basic_function(void)
 			goto failed;
 		}
 
-		/*
-		 * The first '.' may be the initial letter, in which case the
-		 * entire symbol name will be truncated to an empty string in
-		 * cleanup_symbol_name(). Do not test these symbols.
-		 *
-		 * For example:
-		 * cat /proc/kallsyms | awk '{print $3}' | grep -E "^\." | head
-		 * .E_read_words
-		 * .E_leading_bytes
-		 * .E_trailing_bytes
-		 * .E_write_words
-		 * .E_copy
-		 * .str.292.llvm.12122243386960820698
-		 * .str.24.llvm.12122243386960820698
-		 * .str.29.llvm.12122243386960820698
-		 * .str.75.llvm.12122243386960820698
-		 * .str.99.llvm.12122243386960820698
-		 */
-		if (IS_ENABLED(CONFIG_LTO_CLANG) && !namebuf[0])
-			continue;
-
 		lookup_addr = kallsyms_lookup_name(namebuf);
 
 		memset(stat, 0, sizeof(*stat));
diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c
index 80d9c6d77a45..15781acaac1c 100644
--- a/kernel/nsproxy.c
+++ b/kernel/nsproxy.c
@@ -30,7 +30,7 @@
 static struct kmem_cache *nsproxy_cachep;
 
 struct nsproxy init_nsproxy = {
-	.count			= ATOMIC_INIT(1),
+	.count			= REFCOUNT_INIT(1),
 	.uts_ns			= &init_uts_ns,
 #if defined(CONFIG_POSIX_MQUEUE) || defined(CONFIG_SYSVIPC)
 	.ipc_ns			= &init_ipc_ns,
@@ -55,7 +55,7 @@ static inline struct nsproxy *create_nsproxy(void)
 
 	nsproxy = kmem_cache_alloc(nsproxy_cachep, GFP_KERNEL);
 	if (nsproxy)
-		atomic_set(&nsproxy->count, 1);
+		refcount_set(&nsproxy->count, 1);
 	return nsproxy;
 }