Merge tag 'modules-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull module updates from Luis Chamberlain:
 "For the 6.0 merge window the modules code shifts to cleanup and minor
  fixes effort. This becomes much easier to do and review now due to the
  code split to its own directory from effort on the last kernel
  release. I expect to see more of this with time and as we expand on
  test coverage in the future. The cleanups and fixes come from usual
  suspects such as Christophe Leroy and Aaron Tomlin but there are also
  some other contributors.

  One particular minor fix worth mentioning is from Helge Deller, where
  he spotted a *forever* incorrect natural alignment on both ELF section
  header tables:

    * .altinstructions
    * __bug_table sections

  A lot of back and forth went on in trying to determine the ill effects
  of this misalignment being present for years and it has been
  determined there should be no real ill effects unless you have a buggy
  exception handler. Helge actually hit one of these buggy exception
  handlers on parisc which is how he ended up spotting this issue. When
  implemented correctly these paths with incorrect misalignment would
  just mean a performance penalty, but given that we are dealing with
  alternatives on modules and with the __bug_table (where info regardign
  BUG()/WARN() file/line information associated with it is stored) this
  really shouldn't be a big deal.

  The only other change with mentioning is the kmap() with
  kmap_local_page() and my only concern with that was on what is done
  after preemption, but the virtual addresses are restored after
  preemption. This is only used on module decompression.

  This all has sit on linux-next for a while except the kmap stuff which
  has been there for 3 weeks"

* tag 'modules-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  module: Replace kmap() with kmap_local_page()
  module: Show the last unloaded module's taint flag(s)
  module: Use strscpy() for last_unloaded_module
  module: Modify module_flags() to accept show_state argument
  module: Move module's Kconfig items in kernel/module/
  MAINTAINERS: Update file list for module maintainers
  module: Use vzalloc() instead of vmalloc()/memset(0)
  modules: Ensure natural alignment for .altinstructions and __bug_table sections
  module: Increase readability of module_kallsyms_lookup_name()
  module: Fix ERRORs reported by checkpatch.pl
  module: Add support for default value for module async_probe

6 files changed, 356 insertions, 33 deletions

diff --git a/kernel/module/Kconfig b/kernel/module/Kconfig
new file mode 100644
index 000000000000..26ea5d04f56c
--- /dev/null
+++ b/kernel/module/Kconfig
@@ -0,0 +1,293 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menuconfig MODULES
+	bool "Enable loadable module support"
+	modules
+	help
+	  Kernel modules are small pieces of compiled code which can
+	  be inserted in the running kernel, rather than being
+	  permanently built into the kernel.  You use the "modprobe"
+	  tool to add (and sometimes remove) them.  If you say Y here,
+	  many parts of the kernel can be built as modules (by
+	  answering M instead of Y where indicated): this is most
+	  useful for infrequently used options which are not required
+	  for booting.  For more information, see the man pages for
+	  modprobe, lsmod, modinfo, insmod and rmmod.
+
+	  If you say Y here, you will need to run "make
+	  modules_install" to put the modules under /lib/modules/
+	  where modprobe can find them (you may need to be root to do
+	  this).
+
+	  If unsure, say Y.
+
+if MODULES
+
+config MODULE_FORCE_LOAD
+	bool "Forced module loading"
+	default n
+	help
+	  Allow loading of modules without version information (ie. modprobe
+	  --force).  Forced module loading sets the 'F' (forced) taint flag and
+	  is usually a really bad idea.
+
+config MODULE_UNLOAD
+	bool "Module unloading"
+	help
+	  Without this option you will not be able to unload any
+	  modules (note that some modules may not be unloadable
+	  anyway), which makes your kernel smaller, faster
+	  and simpler.  If unsure, say Y.
+
+config MODULE_FORCE_UNLOAD
+	bool "Forced module unloading"
+	depends on MODULE_UNLOAD
+	help
+	  This option allows you to force a module to unload, even if the
+	  kernel believes it is unsafe: the kernel will remove the module
+	  without waiting for anyone to stop using it (using the -f option to
+	  rmmod).  This is mainly for kernel developers and desperate users.
+	  If unsure, say N.
+
+config MODULE_UNLOAD_TAINT_TRACKING
+	bool "Tainted module unload tracking"
+	depends on MODULE_UNLOAD
+	default n
+	help
+	  This option allows you to maintain a record of each unloaded
+	  module that tainted the kernel. In addition to displaying a
+	  list of linked (or loaded) modules e.g. on detection of a bad
+	  page (see bad_page()), the aforementioned details are also
+	  shown. If unsure, say N.
+
+config MODVERSIONS
+	bool "Module versioning support"
+	help
+	  Usually, you have to use modules compiled with your kernel.
+	  Saying Y here makes it sometimes possible to use modules
+	  compiled for different kernels, by adding enough information
+	  to the modules to (hopefully) spot any changes which would
+	  make them incompatible with the kernel you are running.  If
+	  unsure, say N.
+
+config ASM_MODVERSIONS
+	bool
+	default HAVE_ASM_MODVERSIONS && MODVERSIONS
+	help
+	  This enables module versioning for exported symbols also from
+	  assembly. This can be enabled only when the target architecture
+	  supports it.
+
+config MODULE_SRCVERSION_ALL
+	bool "Source checksum for all modules"
+	help
+	  Modules which contain a MODULE_VERSION get an extra "srcversion"
+	  field inserted into their modinfo section, which contains a
+	  sum of the source files which made it.  This helps maintainers
+	  see exactly which source was used to build a module (since
+	  others sometimes change the module source without updating
+	  the version).  With this option, such a "srcversion" field
+	  will be created for all modules.  If unsure, say N.
+
+config MODULE_SIG
+	bool "Module signature verification"
+	select MODULE_SIG_FORMAT
+	help
+	  Check modules for valid signatures upon load: the signature
+	  is simply appended to the module. For more information see
+	  <file:Documentation/admin-guide/module-signing.rst>.
+
+	  Note that this option adds the OpenSSL development packages as a
+	  kernel build dependency so that the signing tool can use its crypto
+	  library.
+
+	  You should enable this option if you wish to use either
+	  CONFIG_SECURITY_LOCKDOWN_LSM or lockdown functionality imposed via
+	  another LSM - otherwise unsigned modules will be loadable regardless
+	  of the lockdown policy.
+
+	  !!!WARNING!!!  If you enable this option, you MUST make sure that the
+	  module DOES NOT get stripped after being signed.  This includes the
+	  debuginfo strip done by some packagers (such as rpmbuild) and
+	  inclusion into an initramfs that wants the module size reduced.
+
+config MODULE_SIG_FORCE
+	bool "Require modules to be validly signed"
+	depends on MODULE_SIG
+	help
+	  Reject unsigned modules or signed modules for which we don't have a
+	  key.  Without this, such modules will simply taint the kernel.
+
+config MODULE_SIG_ALL
+	bool "Automatically sign all modules"
+	default y
+	depends on MODULE_SIG || IMA_APPRAISE_MODSIG
+	help
+	  Sign all modules during make modules_install. Without this option,
+	  modules must be signed manually, using the scripts/sign-file tool.
+
+comment "Do not forget to sign required modules with scripts/sign-file"
+	depends on MODULE_SIG_FORCE && !MODULE_SIG_ALL
+
+choice
+	prompt "Which hash algorithm should modules be signed with?"
+	depends on MODULE_SIG || IMA_APPRAISE_MODSIG
+	help
+	  This determines which sort of hashing algorithm will be used during
+	  signature generation.  This algorithm _must_ be built into the kernel
+	  directly so that signature verification can take place.  It is not
+	  possible to load a signed module containing the algorithm to check
+	  the signature on that module.
+
+config MODULE_SIG_SHA1
+	bool "Sign modules with SHA-1"
+	select CRYPTO_SHA1
+
+config MODULE_SIG_SHA224
+	bool "Sign modules with SHA-224"
+	select CRYPTO_SHA256
+
+config MODULE_SIG_SHA256
+	bool "Sign modules with SHA-256"
+	select CRYPTO_SHA256
+
+config MODULE_SIG_SHA384
+	bool "Sign modules with SHA-384"
+	select CRYPTO_SHA512
+
+config MODULE_SIG_SHA512
+	bool "Sign modules with SHA-512"
+	select CRYPTO_SHA512
+
+endchoice
+
+config MODULE_SIG_HASH
+	string
+	depends on MODULE_SIG || IMA_APPRAISE_MODSIG
+	default "sha1" if MODULE_SIG_SHA1
+	default "sha224" if MODULE_SIG_SHA224
+	default "sha256" if MODULE_SIG_SHA256
+	default "sha384" if MODULE_SIG_SHA384
+	default "sha512" if MODULE_SIG_SHA512
+
+choice
+	prompt "Module compression mode"
+	help
+	  This option allows you to choose the algorithm which will be used to
+	  compress modules when 'make modules_install' is run. (or, you can
+	  choose to not compress modules at all.)
+
+	  External modules will also be compressed in the same way during the
+	  installation.
+
+	  For modules inside an initrd or initramfs, it's more efficient to
+	  compress the whole initrd or initramfs instead.
+
+	  This is fully compatible with signed modules.
+
+	  Please note that the tool used to load modules needs to support the
+	  corresponding algorithm. module-init-tools MAY support gzip, and kmod
+	  MAY support gzip, xz and zstd.
+
+	  Your build system needs to provide the appropriate compression tool
+	  to compress the modules.
+
+	  If in doubt, select 'None'.
+
+config MODULE_COMPRESS_NONE
+	bool "None"
+	help
+	  Do not compress modules. The installed modules are suffixed
+	  with .ko.
+
+config MODULE_COMPRESS_GZIP
+	bool "GZIP"
+	help
+	  Compress modules with GZIP. The installed modules are suffixed
+	  with .ko.gz.
+
+config MODULE_COMPRESS_XZ
+	bool "XZ"
+	help
+	  Compress modules with XZ. The installed modules are suffixed
+	  with .ko.xz.
+
+config MODULE_COMPRESS_ZSTD
+	bool "ZSTD"
+	help
+	  Compress modules with ZSTD. The installed modules are suffixed
+	  with .ko.zst.
+
+endchoice
+
+config MODULE_DECOMPRESS
+	bool "Support in-kernel module decompression"
+	depends on MODULE_COMPRESS_GZIP || MODULE_COMPRESS_XZ
+	select ZLIB_INFLATE if MODULE_COMPRESS_GZIP
+	select XZ_DEC if MODULE_COMPRESS_XZ
+	help
+
+	  Support for decompressing kernel modules by the kernel itself
+	  instead of relying on userspace to perform this task. Useful when
+	  load pinning security policy is enabled.
+
+	  If unsure, say N.
+
+config MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
+	bool "Allow loading of modules with missing namespace imports"
+	help
+	  Symbols exported with EXPORT_SYMBOL_NS*() are considered exported in
+	  a namespace. A module that makes use of a symbol exported with such a
+	  namespace is required to import the namespace via MODULE_IMPORT_NS().
+	  There is no technical reason to enforce correct namespace imports,
+	  but it creates consistency between symbols defining namespaces and
+	  users importing namespaces they make use of. This option relaxes this
+	  requirement and lifts the enforcement when loading a module.
+
+	  If unsure, say N.
+
+config MODPROBE_PATH
+	string "Path to modprobe binary"
+	default "/sbin/modprobe"
+	help
+	  When kernel code requests a module, it does so by calling
+	  the "modprobe" userspace utility. This option allows you to
+	  set the path where that binary is found. This can be changed
+	  at runtime via the sysctl file
+	  /proc/sys/kernel/modprobe. Setting this to the empty string
+	  removes the kernel's ability to request modules (but
+	  userspace can still load modules explicitly).
+
+config TRIM_UNUSED_KSYMS
+	bool "Trim unused exported kernel symbols" if EXPERT
+	depends on !COMPILE_TEST
+	help
+	  The kernel and some modules make many symbols available for
+	  other modules to use via EXPORT_SYMBOL() and variants. Depending
+	  on the set of modules being selected in your kernel configuration,
+	  many of those exported symbols might never be used.
+
+	  This option allows for unused exported symbols to be dropped from
+	  the build. In turn, this provides the compiler more opportunities
+	  (especially when using LTO) for optimizing the code and reducing
+	  binary size.  This might have some security advantages as well.
+
+	  If unsure, or if you need to build out-of-tree modules, say N.
+
+config UNUSED_KSYMS_WHITELIST
+	string "Whitelist of symbols to keep in ksymtab"
+	depends on TRIM_UNUSED_KSYMS
+	help
+	  By default, all unused exported symbols will be un-exported from the
+	  build when TRIM_UNUSED_KSYMS is selected.
+
+	  UNUSED_KSYMS_WHITELIST allows to whitelist symbols that must be kept
+	  exported at all times, even in absence of in-tree users. The value to
+	  set here is the path to a text file containing the list of symbols,
+	  one per line. The path can be absolute, or relative to the kernel
+	  source tree.
+
+config MODULES_TREE_LOOKUP
+	def_bool y
+	depends on PERF_EVENTS || TRACING || CFI_CLANG
+
+endif # MODULES
diff --git a/kernel/module/decompress.c b/kernel/module/decompress.c
index 2fc7081dd7c1..4d0bcb3d9e44 100644
--- a/kernel/module/decompress.c
+++ b/kernel/module/decompress.c
@@ -119,10 +119,10 @@ static ssize_t module_gzip_decompress(struct load_info *info,
 			goto out_inflate_end;
 		}
 
-		s.next_out = kmap(page);
+		s.next_out = kmap_local_page(page);
 		s.avail_out = PAGE_SIZE;
 		rc = zlib_inflate(&s, 0);
-		kunmap(page);
+		kunmap_local(s.next_out);
 
 		new_size += PAGE_SIZE - s.avail_out;
 	} while (rc == Z_OK);
@@ -178,11 +178,11 @@ static ssize_t module_xz_decompress(struct load_info *info,
 			goto out;
 		}
 
-		xz_buf.out = kmap(page);
+		xz_buf.out = kmap_local_page(page);
 		xz_buf.out_pos = 0;
 		xz_buf.out_size = PAGE_SIZE;
 		xz_ret = xz_dec_run(xz_dec, &xz_buf);
-		kunmap(page);
+		kunmap_local(xz_buf.out);
 
 		new_size += xz_buf.out_pos;
 	} while (xz_buf.out_pos == PAGE_SIZE && xz_ret == XZ_OK);
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index ec104c2950c3..680d980a4fb2 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -103,7 +103,7 @@ struct module *find_module_all(const char *name, size_t len, bool even_unformed)
 int cmp_name(const void *name, const void *sym);
 long module_get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr,
 		       unsigned int section);
-char *module_flags(struct module *mod, char *buf);
+char *module_flags(struct module *mod, char *buf, bool show_state);
 size_t module_flags_taint(unsigned long taints, char *buf);
 
 static inline void module_assert_mutex_or_preempt(void)
diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c
index 77e75bead569..f5c5c9175333 100644
--- a/kernel/module/kallsyms.c
+++ b/kernel/module/kallsyms.c
@@ -457,26 +457,39 @@ unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name)
 	return 0;
 }
 
-/* Look for this name: can be of form module:name. */
-unsigned long module_kallsyms_lookup_name(const char *name)
+static unsigned long __module_kallsyms_lookup_name(const char *name)
 {
 	struct module *mod;
 	char *colon;
-	unsigned long ret = 0;
+
+	colon = strnchr(name, MODULE_NAME_LEN, ':');
+	if (colon) {
+		mod = find_module_all(name, colon - name, false);
+		if (mod)
+			return find_kallsyms_symbol_value(mod, colon + 1);
+		return 0;
+	}
+
+	list_for_each_entry_rcu(mod, &modules, list) {
+		unsigned long ret;
+
+		if (mod->state == MODULE_STATE_UNFORMED)
+			continue;
+		ret = find_kallsyms_symbol_value(mod, name);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
+/* Look for this name: can be of form module:name. */
+unsigned long module_kallsyms_lookup_name(const char *name)
+{
+	unsigned long ret;
 
 	/* Don't lock: we're in enough trouble already. */
 	preempt_disable();
-	if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) {
-		if ((mod = find_module_all(name, colon - name, false)) != NULL)
-			ret = find_kallsyms_symbol_value(mod, colon + 1);
-	} else {
-		list_for_each_entry_rcu(mod, &modules, list) {
-			if (mod->state == MODULE_STATE_UNFORMED)
-				continue;
-			if ((ret = find_kallsyms_symbol_value(mod, name)) != 0)
-				break;
-		}
-	}
+	ret = __module_kallsyms_lookup_name(name);
 	preempt_enable();
 	return ret;
 }
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 57fc2821be63..6a477c622544 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -119,7 +119,7 @@ static void mod_update_bounds(struct module *mod)
 }
 
 /* Block module loading/unloading? */
-int modules_disabled = 0;
+int modules_disabled;
 core_param(nomodule, modules_disabled, bint, 0);
 
 /* Waiting for a module to finish initializing? */
@@ -524,7 +524,10 @@ static struct module_attribute modinfo_##field = {                    \
 MODINFO_ATTR(version);
 MODINFO_ATTR(srcversion);
 
-static char last_unloaded_module[MODULE_NAME_LEN+1];
+static struct {
+	char name[MODULE_NAME_LEN + 1];
+	char taints[MODULE_FLAGS_BUF_SIZE];
+} last_unloaded_module;
 
 #ifdef CONFIG_MODULE_UNLOAD
 
@@ -694,6 +697,7 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 {
 	struct module *mod;
 	char name[MODULE_NAME_LEN];
+	char buf[MODULE_FLAGS_BUF_SIZE];
 	int ret, forced = 0;
 
 	if (!capable(CAP_SYS_MODULE) || modules_disabled)
@@ -753,8 +757,9 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 
 	async_synchronize_full();
 
-	/* Store the name of the last unloaded module for diagnostic purposes */
-	strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
+	/* Store the name and taints of the last unloaded module for diagnostic purposes */
+	strscpy(last_unloaded_module.name, mod->name, sizeof(last_unloaded_module.name));
+	strscpy(last_unloaded_module.taints, module_flags(mod, buf, false), sizeof(last_unloaded_module.taints));
 
 	free_module(mod);
 	/* someone could wait for the module in add_unformed_module() */
@@ -2151,7 +2156,7 @@ static int move_module(struct module *mod, struct load_info *info)
 
 #ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
 	/* Do the allocs. */
-	ptr = vmalloc(mod->data_layout.size);
+	ptr = vzalloc(mod->data_layout.size);
 	/*
 	 * The pointer to this block is stored in the module structure
 	 * which is inside the block. Just mark it as not being a
@@ -2164,7 +2169,6 @@ static int move_module(struct module *mod, struct load_info *info)
 		return -ENOMEM;
 	}
 
-	memset(ptr, 0, mod->data_layout.size);
 	mod->data_layout.base = ptr;
 #endif
 	/* Transfer each section which specifies SHF_ALLOC */
@@ -2423,6 +2427,12 @@ static void do_free_init(struct work_struct *w)
 	}
 }
 
+#undef MODULE_PARAM_PREFIX
+#define MODULE_PARAM_PREFIX "module."
+/* Default value for module->async_probe_requested */
+static bool async_probe;
+module_param(async_probe, bool, 0644);
+
 /*
  * This is where the real work happens.
  *
@@ -2643,7 +2653,8 @@ static int unknown_module_param_cb(char *param, char *val, const char *modname,
 	int ret;
 
 	if (strcmp(param, "async_probe") == 0) {
-		mod->async_probe_requested = true;
+		if (strtobool(val, &mod->async_probe_requested))
+			mod->async_probe_requested = true;
 		return 0;
 	}
 
@@ -2810,6 +2821,8 @@ static int load_module(struct load_info *info, const char __user *uargs,
 	if (err)
 		goto bug_cleanup;
 
+	mod->async_probe_requested = async_probe;
+
 	/* Module is ready to execute: parsing args may do that. */
 	after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
 				  -32768, 32767, mod,
@@ -2984,24 +2997,27 @@ static void cfi_cleanup(struct module *mod)
 }
 
 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
-char *module_flags(struct module *mod, char *buf)
+char *module_flags(struct module *mod, char *buf, bool show_state)
 {
 	int bx = 0;
 
 	BUG_ON(mod->state == MODULE_STATE_UNFORMED);
+	if (!mod->taints && !show_state)
+		goto out;
 	if (mod->taints ||
 	    mod->state == MODULE_STATE_GOING ||
 	    mod->state == MODULE_STATE_COMING) {
 		buf[bx++] = '(';
 		bx += module_flags_taint(mod->taints, buf + bx);
 		/* Show a - for module-is-being-unloaded */
-		if (mod->state == MODULE_STATE_GOING)
+		if (mod->state == MODULE_STATE_GOING && show_state)
 			buf[bx++] = '-';
 		/* Show a + for module-is-being-loaded */
-		if (mod->state == MODULE_STATE_COMING)
+		if (mod->state == MODULE_STATE_COMING && show_state)
 			buf[bx++] = '+';
 		buf[bx++] = ')';
 	}
+out:
 	buf[bx] = '\0';
 
 	return buf;
@@ -3134,12 +3150,13 @@ void print_modules(void)
 	list_for_each_entry_rcu(mod, &modules, list) {
 		if (mod->state == MODULE_STATE_UNFORMED)
 			continue;
-		pr_cont(" %s%s", mod->name, module_flags(mod, buf));
+		pr_cont(" %s%s", mod->name, module_flags(mod, buf, true));
 	}
 
 	print_unloaded_tainted_modules();
 	preempt_enable();
-	if (last_unloaded_module[0])
-		pr_cont(" [last unloaded: %s]", last_unloaded_module);
+	if (last_unloaded_module.name[0])
+		pr_cont(" [last unloaded: %s%s]", last_unloaded_module.name,
+			last_unloaded_module.taints);
 	pr_cont("\n");
 }
diff --git a/kernel/module/procfs.c b/kernel/module/procfs.c
index 9a8f4f0f6329..cf5b9f1e6ec4 100644
--- a/kernel/module/procfs.c
+++ b/kernel/module/procfs.c
@@ -91,7 +91,7 @@ static int m_show(struct seq_file *m, void *p)
 
 	/* Taints info */
 	if (mod->taints)
-		seq_printf(m, " %s", module_flags(mod, buf));
+		seq_printf(m, " %s", module_flags(mod, buf, true));
 
 	seq_puts(m, "\n");
 	return 0;