From: Andreas Gruenbacher <agruen@suse.de>
Subject: Novell/external support flag in modules
Patch-mainline: Never, SLES feature
References: bsc#148091
Upon module load, check if a module is supported, and set the
N (TAINT_NO_SUPPORT) or X (TAINT_EXTERNAL_SUPPORT) tail flags
for unsupported or externally suported modules.
Changes:
* Feb 21 2008 - jeffm
- 2.6.25 claimed -S and bumped the flags up a bit, modpost now uses -N
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
---
Documentation/admin-guide/kernel-parameters.txt | 8 ++
Documentation/sysctl/kernel.txt | 12 +++
Makefile | 5 +
include/linux/kernel.h | 15 ++++
include/linux/module.h | 3
init/Kconfig.suse | 18 +++++
kernel/ksysfs.c | 27 +++++++
kernel/module.c | 83 ++++++++++++++++++++++++
kernel/panic.c | 6 +
kernel/sysctl.c | 9 ++
scripts/Makefile.modpost | 6 +
scripts/mod/modpost.c | 79 ++++++++++++++++++++++
12 files changed, 269 insertions(+), 2 deletions(-)
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4766,6 +4766,14 @@
unknown_nmi_panic
[X86] Cause panic on unknown NMI.
+ unsupported Allow loading of unsupported kernel modules:
+ 0 = only allow supported modules,
+ 1 = warn when loading unsupported modules,
+ 2 = don't warn.
+
+ CONFIG_SUSE_KERNEL_SUPPORTED must be enabled for this
+ to have any effect.
+
usbcore.authorized_default=
[USB] Default USB device authorization:
(default -1 = authorized except for wireless USB,
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -974,6 +974,18 @@ can be ORed together:
signature.
16384 - A soft lockup has previously occurred on the system.
32768 - The kernel has been live patched.
+ 0x40000000 - An unsupported kernel module was loaded.
+ 0x80000000 - An kernel module with external support was loaded.
+
+==============================================================
+
+unsupported:
+
+Allow to load unsupported kernel modules:
+
+ 0 - refuse to load unsupported modules,
+ 1 - warn when loading unsupported modules,
+ 2 - don't warn.
==============================================================
--- a/Makefile
+++ b/Makefile
@@ -412,6 +412,11 @@ KBUILD_CFLAGS_MODULE := -DMODULE
KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
LDFLAGS :=
+# Warn about unsupported modules in kernels built inside Autobuild
+ifneq ($(wildcard /.buildenv),)
+CFLAGS += -DUNSUPPORTED_MODULES=2
+endif
+
# Read KERNELRELEASE from include/config/kernel.release (if it exists)
KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -461,6 +461,9 @@ extern int panic_on_unrecovered_nmi;
extern int panic_on_io_nmi;
extern int panic_on_warn;
extern int sysctl_panic_on_rcu_stall;
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+extern int suse_unsupported;
+#endif
extern int sysctl_panic_on_stackoverflow;
extern bool crash_kexec_post_notifiers;
@@ -519,7 +522,19 @@ extern enum system_states {
#define TAINT_UNSIGNED_MODULE 13
#define TAINT_SOFTLOCKUP 14
#define TAINT_LIVEPATCH 15
+/* !!! Keep TAINT_FLAGS_COUNT in sync !!! */
+
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+/*
+ * Take the upper bits to hopefully allow them
+ * to stay the same for more than one release.
+ */
+#define TAINT_NO_SUPPORT 30
+#define TAINT_EXTERNAL_SUPPORT 31
+#define TAINT_FLAGS_COUNT 32
+#else
#define TAINT_FLAGS_COUNT 16
+#endif
struct taint_flag {
char c_true; /* character printed when tainted */
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -496,6 +496,9 @@ bool is_module_address(unsigned long add
bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
bool is_module_percpu_address(unsigned long addr);
bool is_module_text_address(unsigned long addr);
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+const char *supported_printable(int taint);
+#endif
static inline bool within_module_core(unsigned long addr,
const struct module *mod)
--- a/init/Kconfig.suse
+++ b/init/Kconfig.suse
@@ -1,2 +1,20 @@
config SUSE_KERNEL
def_bool y
+
+config SUSE_KERNEL_SUPPORTED
+ bool "Enable enterprise support facility"
+ depends on SUSE_KERNEL
+ help
+ This feature enables the handling of the "supported" module flag.
+ This flag can be used to report unsupported module loads or even
+ refuse them entirely. It is useful when ensuring that the kernel
+ remains in a state that SUSE, or its technical partners, is
+ prepared to support.
+
+ Modules in the list of supported modules will be marked supported
+ on build. The default enforcement mode is to report, but not
+ deny, loading of unsupported modules.
+
+ If you aren't building a kernel for an enterprise distribution,
+ say n.
+
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -215,6 +215,30 @@ static struct bin_attribute notes_attr _
struct kobject *kernel_kobj;
EXPORT_SYMBOL_GPL(kernel_kobj);
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+const char *supported_printable(int taint)
+{
+ int mask = (1 << TAINT_PROPRIETARY_MODULE) | (1 << TAINT_NO_SUPPORT);
+ if ((taint & mask) == mask)
+ return "No, Proprietary and Unsupported modules are loaded";
+ else if (taint & (1 << TAINT_PROPRIETARY_MODULE))
+ return "No, Proprietary modules are loaded";
+ else if (taint & (1 << TAINT_NO_SUPPORT))
+ return "No, Unsupported modules are loaded";
+ else if (taint & (1 << TAINT_EXTERNAL_SUPPORT))
+ return "Yes, External";
+ else
+ return "Yes";
+}
+
+static ssize_t supported_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%s\n", supported_printable(get_taint()));
+}
+KERNEL_ATTR_RO(supported);
+#endif
+
static struct attribute * kernel_attrs[] = {
&fscaps_attr.attr,
&uevent_seqnum_attr.attr,
@@ -236,6 +260,9 @@ static struct attribute * kernel_attrs[]
&rcu_expedited_attr.attr,
&rcu_normal_attr.attr,
#endif
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+ &supported_attr.attr,
+#endif
NULL
};
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -90,6 +90,22 @@
/* If this is set, the section belongs in the init part of the module */
#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+/* Allow unsupported modules switch. */
+#ifdef UNSUPPORTED_MODULES
+int suse_unsupported = UNSUPPORTED_MODULES;
+#else
+int suse_unsupported = 2; /* don't warn when loading unsupported modules. */
+#endif
+
+static int __init unsupported_setup(char *str)
+{
+ get_option(&str, &suse_unsupported);
+ return 1;
+}
+__setup("unsupported=", unsupported_setup);
+#endif
+
/*
* Mutex protects:
* 1) List of modules (also safely readable with preempt_disable),
@@ -1156,6 +1172,12 @@ static size_t module_flags_taint(struct
buf[l++] = taint_flags[i].c_true;
}
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+ if (mod->taints & (1 << TAINT_NO_SUPPORT))
+ buf[l++] = 'N';
+ if (mod->taints & (1 << TAINT_EXTERNAL_SUPPORT))
+ buf[l++] = 'X';
+#endif
return l;
}
@@ -1228,6 +1250,33 @@ static ssize_t show_taint(struct module_
static struct module_attribute modinfo_taint =
__ATTR(taint, 0444, show_taint, NULL);
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+static void setup_modinfo_supported(struct module *mod, const char *s)
+{
+ if (!s) {
+ mod->taints |= (1 << TAINT_NO_SUPPORT);
+ return;
+ }
+
+ if (strcmp(s, "external") == 0)
+ mod->taints |= (1 << TAINT_EXTERNAL_SUPPORT);
+ else if (strcmp(s, "yes"))
+ mod->taints |= (1 << TAINT_NO_SUPPORT);
+}
+
+static ssize_t show_modinfo_supported(struct module_attribute *mattr,
+ struct module_kobject *mk, char *buffer)
+{
+ return sprintf(buffer, "%s\n", supported_printable(mk->mod->taints));
+}
+
+static struct module_attribute modinfo_supported = {
+ .attr = { .name = "supported", .mode = 0444 },
+ .show = show_modinfo_supported,
+ .setup = setup_modinfo_supported,
+};
+#endif
+
static struct module_attribute *modinfo_attrs[] = {
&module_uevent,
&modinfo_version,
@@ -1236,6 +1285,9 @@ static struct module_attribute *modinfo_
&modinfo_coresize,
&modinfo_initsize,
&modinfo_taint,
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+ &modinfo_supported,
+#endif
#ifdef CONFIG_MODULE_UNLOAD
&modinfo_refcnt,
#endif
@@ -1790,8 +1842,36 @@ static int mod_sysfs_setup(struct module
add_sect_attrs(mod, info);
add_notes_attrs(mod, info);
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+ if (mod->taints & (1 << TAINT_EXTERNAL_SUPPORT))
+ add_taint(TAINT_EXTERNAL_SUPPORT, LOCKDEP_STILL_OK);
+ else if (mod->taints & (1 << TAINT_NO_SUPPORT)) {
+ if (suse_unsupported == 0) {
+ printk(KERN_WARNING "%s: module not supported by "
+ "SUSE, refusing to load. To override, echo "
+ "1 > /proc/sys/kernel/unsupported\n", mod->name);
+ err = -ENOEXEC;
+ goto out_remove_attrs;
+ }
+ add_taint(TAINT_NO_SUPPORT, LOCKDEP_STILL_OK);
+ if (suse_unsupported == 1) {
+ printk(KERN_WARNING "%s: module is not supported by "
+ "SUSE. Our support organization may not be "
+ "able to address your support request if it "
+ "involves a kernel fault.\n", mod->name);
+ }
+ }
+#endif
+
return 0;
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+out_remove_attrs:
+ remove_notes_attrs(mod);
+ remove_sect_attrs(mod);
+ del_usage_links(mod);
+ module_remove_modinfo_attrs(mod);
+#endif
out_unreg_param:
module_param_sysfs_remove(mod);
out_unreg_holders:
@@ -4492,6 +4572,9 @@ void print_modules(void)
if (last_unloaded_module[0])
pr_cont(" [last unloaded: %s]", last_unloaded_module);
pr_cont("\n");
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+ printk("Supported: %s\n", supported_printable(get_taint()));
+#endif
}
#ifdef CONFIG_MODVERSIONS
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -325,6 +325,10 @@ const struct taint_flag taint_flags[TAIN
{ 'E', ' ', true }, /* TAINT_UNSIGNED_MODULE */
{ 'L', ' ', false }, /* TAINT_SOFTLOCKUP */
{ 'K', ' ', true }, /* TAINT_LIVEPATCH */
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+ { 'N', ' ', true }, /* TAINT_NO_SUPPORT */
+ { 'X', ' ', true }, /* TAINT_EXTERNAL_SUPPORT */
+#endif
};
/**
@@ -346,6 +350,8 @@ const struct taint_flag taint_flags[TAIN
* 'E' - Unsigned module has been loaded.
* 'L' - A soft lockup has previously occurred.
* 'K' - Kernel has been live patched.
+ * 'N' - Unsuported modules loaded.
+ * 'X' - Modules with external support loaded.
*
* The string is overwritten by the next call to print_tainted().
*/
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -825,6 +825,15 @@ static struct ctl_table kern_table[] = {
.extra1 = &pid_max_min,
.extra2 = &pid_max_max,
},
+#if defined(CONFIG_MODULES) && defined(CONFIG_SUSE_KERNEL_SUPPORTED)
+ {
+ .procname = "unsupported",
+ .data = &suse_unsupported,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+#endif
{
.procname = "panic_on_oops",
.data = &panic_on_oops,
--- a/scripts/Makefile.modpost
+++ b/scripts/Makefile.modpost
@@ -78,7 +78,11 @@ modpost = scripts/mod/modpost
$(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \
$(if $(CONFIG_DEBUG_SECTION_MISMATCH),,-S) \
$(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \
- $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w)
+ $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w) \
+ $(if $(CONFIG_SUSE_KERNEL_SUPPORTED), \
+ -N $(firstword $(wildcard $(dir $(MODVERDIR))/Module.supported \
+ $(objtree)/Module.supported \
+ $(srctree)/Module.supported /dev/null)))
MODPOST_OPT=$(subst -i,-n,$(filter -i,$(MAKEFLAGS)))
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -1940,6 +1940,50 @@ static char *remove_dot(char *s)
return s;
}
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+void *supported_file;
+unsigned long supported_size;
+
+static const char *supported(struct module *mod)
+{
+ unsigned long pos = 0;
+ char *line;
+
+ /* In a first shot, do a simple linear scan. */
+ while ((line = get_next_line(&pos, supported_file,
+ supported_size))) {
+ const char *basename, *how = "yes";
+ char *l = line;
+
+ /* optional type-of-support flag */
+ for (l = line; *l != '\0'; l++) {
+ if (*l == ' ' || *l == '\t') {
+ *l = '\0';
+ how = l + 1;
+ break;
+ }
+ }
+
+ /* skip directory components */
+ if ((l = strrchr(line, '/')))
+ line = l + 1;
+ /* strip .ko extension */
+ l = line + strlen(line);
+ if (l - line > 3 && !strcmp(l-3, ".ko"))
+ *(l-3) = '\0';
+
+ /* skip directory components */
+ if ((basename = strrchr(mod->name, '/')))
+ basename++;
+ else
+ basename = mod->name;
+ if (!strcmp(basename, line))
+ return how;
+ }
+ return NULL;
+}
+#endif
+
static void read_symbols(char *modname)
{
const char *symname;
@@ -2167,6 +2211,15 @@ static void add_staging_flag(struct buff
*/
#define MODULE_NAME_LEN (64 - sizeof(Elf_Addr))
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+static void add_supported_flag(struct buffer *b, struct module *mod)
+{
+ const char *how = supported(mod);
+ if (how)
+ buf_printf(b, "\nMODULE_INFO(supported, \"%s\");\n", how);
+}
+#endif
+
/**
* Record CRCs for unresolved symbols
**/
@@ -2314,6 +2367,15 @@ static void write_if_changed(struct buff
fclose(file);
}
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+static void read_supported(const char *fname)
+{
+ supported_file = grab_file(fname, &supported_size);
+ if (!supported_file)
+ ; /* ignore error */
+}
+#endif
+
/* parse Module.symvers file. line format:
* 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
**/
@@ -2410,12 +2472,15 @@ int main(int argc, char **argv)
struct buffer buf = { };
char *kernel_read = NULL, *module_read = NULL;
char *dump_write = NULL, *files_source = NULL;
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+ const char *supported = NULL;
+#endif
int opt;
int err;
struct ext_sym_list *extsym_iter;
struct ext_sym_list *extsym_start = NULL;
- while ((opt = getopt(argc, argv, "i:I:e:mnsST:o:awM:K:E")) != -1) {
+ while ((opt = getopt(argc, argv, "i:I:e:mnsST:o:awM:K:EN:")) != -1) {
switch (opt) {
case 'i':
kernel_read = optarg;
@@ -2459,11 +2524,20 @@ int main(int argc, char **argv)
case 'E':
sec_mismatch_fatal = 1;
break;
+ case 'N':
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+ supported = optarg;
+#endif
+ break;
default:
exit(1);
}
}
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+ if (supported)
+ read_supported(supported);
+#endif
if (kernel_read)
read_dump(kernel_read, 1);
if (module_read)
@@ -2501,6 +2575,9 @@ int main(int argc, char **argv)
add_intree_flag(&buf, !external_module);
add_retpoline(&buf);
add_staging_flag(&buf, mod->name);
+#ifdef CONFIG_SUSE_KERNEL_SUPPORTED
+ add_supported_flag(&buf, mod);
+#endif
err |= add_versions(&buf, mod);
add_depends(&buf, mod, modules);
add_moddevtable(&buf, mod);