Add a simple klp-convert livepatch selftest that exercises various symbol homonym sympos scenarios. Signed-off-by: Joe Lawrence <joe.lawrence@xxxxxxxxxx> --- lib/livepatch/Makefile | 7 + lib/livepatch/test_klp_convert.h | 14 ++ lib/livepatch/test_klp_convert1.c | 113 +++++++++++++++ lib/livepatch/test_klp_convert2.c | 110 ++++++++++++++ lib/livepatch/test_klp_convert_mod_a.c | 25 ++++ lib/livepatch/test_klp_convert_mod_b.c | 13 ++ .../selftests/livepatch/test-livepatch.sh | 134 ++++++++++++++++++ 7 files changed, 416 insertions(+) create mode 100644 lib/livepatch/test_klp_convert.h create mode 100644 lib/livepatch/test_klp_convert1.c create mode 100644 lib/livepatch/test_klp_convert2.c create mode 100644 lib/livepatch/test_klp_convert_mod_a.c create mode 100644 lib/livepatch/test_klp_convert_mod_b.c diff --git a/lib/livepatch/Makefile b/lib/livepatch/Makefile index dcc912b3478f..ced00515ff84 100644 --- a/lib/livepatch/Makefile +++ b/lib/livepatch/Makefile @@ -7,8 +7,15 @@ obj-$(CONFIG_TEST_LIVEPATCH) += test_klp_atomic_replace.o \ test_klp_callbacks_demo2.o \ test_klp_callbacks_busy.o \ test_klp_callbacks_mod.o \ + test_klp_convert1.o \ + test_klp_convert2.o \ + test_klp_convert_mod.o \ test_klp_livepatch.o \ test_klp_shadow_vars.o \ test_klp_state.o \ test_klp_state2.o \ test_klp_state3.o + +test_klp_convert_mod-y := \ + test_klp_convert_mod_a.o \ + test_klp_convert_mod_b.o diff --git a/lib/livepatch/test_klp_convert.h b/lib/livepatch/test_klp_convert.h new file mode 100644 index 000000000000..5d97bc546d6e --- /dev/null +++ b/lib/livepatch/test_klp_convert.h @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _TEST_KLP_CONVERT_ +#define _TEST_KLP_CONVERT_ + +/* klp-convert symbols - vmlinux */ +extern char *saved_command_line; +/* klp-convert symbols - test_klp_convert_mod.ko */ +extern char driver_name[]; +extern char homonym_string[]; +extern const char *get_homonym_string(void); +extern const char *test_klp_get_driver_name(void); + +#endif diff --git a/lib/livepatch/test_klp_convert1.c b/lib/livepatch/test_klp_convert1.c new file mode 100644 index 000000000000..d4e1163c01cc --- /dev/null +++ b/lib/livepatch/test_klp_convert1.c @@ -0,0 +1,113 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2019 Joe Lawrence <joe.lawrence@xxxxxxxxxx> + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/livepatch.h> +#include "test_klp_convert.h" + +static noinline void print_saved_command_line(void) +{ + pr_info("saved_command_line, 0: %s\n", saved_command_line); +} + +static noinline void print_driver_name(void) +{ + pr_info("driver_name, 0: %s\n", driver_name); + pr_info("test_klp_get_driver_name(), 0: %s\n", test_klp_get_driver_name()); +} + +static noinline void print_homonym_string(void) +{ + pr_info("homonym_string, 1: %s\n", homonym_string); + pr_info("get_homonym_string(), 1: %s\n", get_homonym_string()); +} + +/* provide a sysfs handle to invoke debug functions */ +static int print_debug; +static int print_debug_set(const char *val, const struct kernel_param *kp) +{ + print_saved_command_line(); + print_driver_name(); + print_homonym_string(); + + return 0; +} +static const struct kernel_param_ops print_debug_ops = { + .set = print_debug_set, + .get = param_get_int, +}; +module_param_cb(print_debug, &print_debug_ops, &print_debug, 0200); +MODULE_PARM_DESC(print_debug, "print klp-convert debugging info"); + +/* + * saved_command_line is a unique symbol, so the sympos annotation is + * optional. Provide to test that sympos=0 works correctly. + */ +KLP_MODULE_RELOC(vmlinux) vmlinux_relocs[] = { + KLP_SYMPOS(saved_command_line, 0) +}; + +/* + * driver_name symbols can be found in vmlinux (multiple) and also + * test_klp_convert_mod, therefore the annotation is required to + * clarify that we want the one from test_klp_convert_mod. + * + * test_klp_convert_mod contains multiple homonym_string and + * get_homonym_string symbols, test resolving the first set here and + * the others in test_klp_convert2.c + * + * test_klp_get_driver_name is a uniquely named symbol, test that sympos=0 + * work correctly. + */ +KLP_MODULE_RELOC(test_klp_convert_mod) test_klp_convert_mod_relocs_a[] = { + KLP_SYMPOS(driver_name, 0), + KLP_SYMPOS(homonym_string, 1), + KLP_SYMPOS(get_homonym_string, 1), + KLP_SYMPOS(test_klp_get_driver_name, 0), +}; + +static struct klp_func funcs[] = { + { + }, { } +}; + +static struct klp_object objs[] = { + { + /* name being NULL means vmlinux */ + .funcs = funcs, + }, + { + .name = "test_klp_convert_mod", + .funcs = funcs, + }, { } +}; + +static struct klp_patch patch = { + .mod = THIS_MODULE, + .objs = objs, +}; + +static int test_klp_convert_init(void) +{ + int ret; + + ret = klp_enable_patch(&patch); + if (ret) + return ret; + + return 0; +} + +static void test_klp_convert_exit(void) +{ +} + +module_init(test_klp_convert_init); +module_exit(test_klp_convert_exit); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Joe Lawrence <joe.lawrence@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Livepatch test: klp-convert1"); +MODULE_INFO(livepatch, "Y"); diff --git a/lib/livepatch/test_klp_convert2.c b/lib/livepatch/test_klp_convert2.c new file mode 100644 index 000000000000..2a2a153aa0b9 --- /dev/null +++ b/lib/livepatch/test_klp_convert2.c @@ -0,0 +1,110 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2019 Joe Lawrence <joe.lawrence@xxxxxxxxxx> + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/livepatch.h> +#include "test_klp_convert.h" + +static noinline void print_saved_command_line(void) +{ + pr_info("saved_command_line (auto): %s\n", saved_command_line); +} + +static noinline void print_driver_name(void) +{ + pr_info("driver_name, 0: %s\n", driver_name); + pr_info("test_klp_get_driver_name(), (auto): %s\n", test_klp_get_driver_name()); +} + +static noinline void print_homonym_string(void) +{ + pr_info("homonym_string, 2: %s\n", homonym_string); + pr_info("get_homonym_string(), 2: %s\n", get_homonym_string()); +} + +/* provide a sysfs handle to invoke debug functions */ +static int print_debug; +static int print_debug_set(const char *val, const struct kernel_param *kp) +{ + print_saved_command_line(); + print_driver_name(); + print_homonym_string(); + + return 0; +} +static const struct kernel_param_ops print_debug_ops = { + .set = print_debug_set, + .get = param_get_int, +}; +module_param_cb(print_debug, &print_debug_ops, &print_debug, 0200); +MODULE_PARM_DESC(print_debug, "print klp-convert debugging info"); + +/* + * saved_command_line is a uniquely named symbol, so the sympos + * annotation is optional. Skip it and test that klp-convert can + * resolve the symbol on its own. + */ + +/* + * driver_name symbols can be found in vmlinux (multiple) and also + * test_klp_convert_mod, therefore the annotation is required to + * clarify that we want the one from test_klp_convert_mod. + * + * test_klp_convert_mod contains multiple homonym_string symbols, + * test_klp_convert1.c resolved to the first one, resolve to the + * second one here. + * + * test_klp_get_driver_name is a uniquely named symbol, test klp-convert can + * resolve it automatically. + */ +KLP_MODULE_RELOC(test_klp_convert_mod) test_klp_convert_mod_relocs_a[] = { + KLP_SYMPOS(driver_name, 0), + KLP_SYMPOS(homonym_string, 2), + KLP_SYMPOS(get_homonym_string, 2), +}; + +static struct klp_func funcs[] = { + { + }, { } +}; + +static struct klp_object objs[] = { + { + /* name being NULL means vmlinux */ + .funcs = funcs, + }, + { + .name = "test_klp_convert_mod", + .funcs = funcs, + }, { } +}; + +static struct klp_patch patch = { + .mod = THIS_MODULE, + .objs = objs, +}; + +static int test_klp_convert_init(void) +{ + int ret; + + ret = klp_enable_patch(&patch); + if (ret) + return ret; + + return 0; +} + +static void test_klp_convert_exit(void) +{ +} + +module_init(test_klp_convert_init); +module_exit(test_klp_convert_exit); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Joe Lawrence <joe.lawrence@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Livepatch test: klp-convert2"); +MODULE_INFO(livepatch, "Y"); diff --git a/lib/livepatch/test_klp_convert_mod_a.c b/lib/livepatch/test_klp_convert_mod_a.c new file mode 100644 index 000000000000..ae5e911fbb9b --- /dev/null +++ b/lib/livepatch/test_klp_convert_mod_a.c @@ -0,0 +1,25 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2019 Joe Lawrence <joe.lawrence@xxxxxxxxxx> + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> + +/* Unique symbols that don't need sympos annotation */ +static const char driver_name[] = KBUILD_MODNAME; +__used static const char *test_klp_get_driver_name(void) +{ + return driver_name; +} + +/* Common symbol names that need sympos */ +static const char homonym_string[] = "homonym string A"; +__used static const char *get_homonym_string(void) +{ + return homonym_string; +} + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Joe Lawrence <joe.lawrence@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Livepatch test: klp-convert module"); diff --git a/lib/livepatch/test_klp_convert_mod_b.c b/lib/livepatch/test_klp_convert_mod_b.c new file mode 100644 index 000000000000..5eca8a4cae38 --- /dev/null +++ b/lib/livepatch/test_klp_convert_mod_b.c @@ -0,0 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2019 Joe Lawrence <joe.lawrence@xxxxxxxxxx> + +/* + * A second compilation unit to provide another set of similarly named + * symbols, forcing a livepatch to use sympos annotations. + */ + +static const char homonym_string[] = "homonym string B"; +__used static const char *get_homonym_string(void) +{ + return homonym_string; +} diff --git a/tools/testing/selftests/livepatch/test-livepatch.sh b/tools/testing/selftests/livepatch/test-livepatch.sh index 5fe79ac34be1..25c21ddf30f0 100755 --- a/tools/testing/selftests/livepatch/test-livepatch.sh +++ b/tools/testing/selftests/livepatch/test-livepatch.sh @@ -6,6 +6,10 @@ MOD_LIVEPATCH=test_klp_livepatch MOD_REPLACE=test_klp_atomic_replace +MOD_KLP_CONVERT_MOD=test_klp_convert_mod +MOD_KLP_CONVERT1=test_klp_convert1 +MOD_KLP_CONVERT2=test_klp_convert2 +MOD_KLP_CONVERT_SECTIONS=test_klp_convert_sections setup_config @@ -159,4 +163,134 @@ livepatch: '$MOD_REPLACE': unpatching complete % rmmod $MOD_REPLACE" +# TEST: klp-convert symbols +# - load a livepatch that modifies the output from /proc/cmdline +# including a reference to vmlinux-local symbol that klp-convert +# will process +# - verify correct behavior +# - unload the livepatch and make sure the patch was removed + +start_test "klp-convert symbols" + +saved_cmdline=$(cat /proc/cmdline) + +load_mod $MOD_KLP_CONVERT_MOD + +load_lp $MOD_KLP_CONVERT1 +echo 1 > /sys/module/$MOD_KLP_CONVERT1/parameters/print_debug +disable_lp $MOD_KLP_CONVERT1 +unload_lp $MOD_KLP_CONVERT1 + +load_lp $MOD_KLP_CONVERT2 +echo 1 > /sys/module/$MOD_KLP_CONVERT2/parameters/print_debug +disable_lp $MOD_KLP_CONVERT2 +unload_lp $MOD_KLP_CONVERT2 + +unload_mod $MOD_KLP_CONVERT_MOD + +check_result "% modprobe $MOD_KLP_CONVERT_MOD +% modprobe $MOD_KLP_CONVERT1 +livepatch: enabling patch '$MOD_KLP_CONVERT1' +livepatch: '$MOD_KLP_CONVERT1': initializing patching transition +livepatch: '$MOD_KLP_CONVERT1': starting patching transition +livepatch: '$MOD_KLP_CONVERT1': completing patching transition +livepatch: '$MOD_KLP_CONVERT1': patching complete +$MOD_KLP_CONVERT1: saved_command_line, 0: $saved_cmdline +$MOD_KLP_CONVERT1: driver_name, 0: $MOD_KLP_CONVERT_MOD +$MOD_KLP_CONVERT1: test_klp_get_driver_name(), 0: $MOD_KLP_CONVERT_MOD +$MOD_KLP_CONVERT1: homonym_string, 1: homonym string A +$MOD_KLP_CONVERT1: get_homonym_string(), 1: homonym string A +% echo 0 > /sys/kernel/livepatch/$MOD_KLP_CONVERT1/enabled +livepatch: '$MOD_KLP_CONVERT1': initializing unpatching transition +livepatch: '$MOD_KLP_CONVERT1': starting unpatching transition +livepatch: '$MOD_KLP_CONVERT1': completing unpatching transition +livepatch: '$MOD_KLP_CONVERT1': unpatching complete +% rmmod $MOD_KLP_CONVERT1 +% modprobe $MOD_KLP_CONVERT2 +livepatch: enabling patch '$MOD_KLP_CONVERT2' +livepatch: '$MOD_KLP_CONVERT2': initializing patching transition +livepatch: '$MOD_KLP_CONVERT2': starting patching transition +livepatch: '$MOD_KLP_CONVERT2': completing patching transition +livepatch: '$MOD_KLP_CONVERT2': patching complete +$MOD_KLP_CONVERT2: saved_command_line (auto): $saved_cmdline +$MOD_KLP_CONVERT2: driver_name, 0: $MOD_KLP_CONVERT_MOD +$MOD_KLP_CONVERT2: test_klp_get_driver_name(), (auto): $MOD_KLP_CONVERT_MOD +$MOD_KLP_CONVERT2: homonym_string, 2: homonym string B +$MOD_KLP_CONVERT2: get_homonym_string(), 2: homonym string B +% echo 0 > /sys/kernel/livepatch/$MOD_KLP_CONVERT2/enabled +livepatch: '$MOD_KLP_CONVERT2': initializing unpatching transition +livepatch: '$MOD_KLP_CONVERT2': starting unpatching transition +livepatch: '$MOD_KLP_CONVERT2': completing unpatching transition +livepatch: '$MOD_KLP_CONVERT2': unpatching complete +% rmmod $MOD_KLP_CONVERT2 +% rmmod $MOD_KLP_CONVERT_MOD" + + +# TEST: klp-convert symbols (late module patching) +# - load a livepatch that modifies the output from /proc/cmdline +# including a reference to vmlinux-local symbol that klp-convert +# will process +# - load target module +# - verify correct behavior +# - unload the livepatch + +start_test "klp-convert symbols (late module patching)" + +saved_cmdline=$(cat /proc/cmdline) + +load_lp $MOD_KLP_CONVERT1 +load_mod $MOD_KLP_CONVERT_MOD +echo 1 > /sys/module/$MOD_KLP_CONVERT1/parameters/print_debug +disable_lp $MOD_KLP_CONVERT1 +unload_lp $MOD_KLP_CONVERT1 +unload_mod $MOD_KLP_CONVERT_MOD + +load_lp $MOD_KLP_CONVERT2 +load_mod $MOD_KLP_CONVERT_MOD +echo 1 > /sys/module/$MOD_KLP_CONVERT2/parameters/print_debug +disable_lp $MOD_KLP_CONVERT2 +unload_lp $MOD_KLP_CONVERT2 +unload_mod $MOD_KLP_CONVERT_MOD + +check_result "% modprobe $MOD_KLP_CONVERT1 +livepatch: enabling patch '$MOD_KLP_CONVERT1' +livepatch: '$MOD_KLP_CONVERT1': initializing patching transition +livepatch: '$MOD_KLP_CONVERT1': starting patching transition +livepatch: '$MOD_KLP_CONVERT1': completing patching transition +livepatch: '$MOD_KLP_CONVERT1': patching complete +% modprobe $MOD_KLP_CONVERT_MOD +livepatch: applying patch '$MOD_KLP_CONVERT1' to loading module '$MOD_KLP_CONVERT_MOD' +$MOD_KLP_CONVERT1: saved_command_line, 0: $saved_cmdline +$MOD_KLP_CONVERT1: driver_name, 0: $MOD_KLP_CONVERT_MOD +$MOD_KLP_CONVERT1: test_klp_get_driver_name(), 0: $MOD_KLP_CONVERT_MOD +$MOD_KLP_CONVERT1: homonym_string, 1: homonym string A +$MOD_KLP_CONVERT1: get_homonym_string(), 1: homonym string A +% echo 0 > /sys/kernel/livepatch/$MOD_KLP_CONVERT1/enabled +livepatch: '$MOD_KLP_CONVERT1': initializing unpatching transition +livepatch: '$MOD_KLP_CONVERT1': starting unpatching transition +livepatch: '$MOD_KLP_CONVERT1': completing unpatching transition +livepatch: '$MOD_KLP_CONVERT1': unpatching complete +% rmmod $MOD_KLP_CONVERT1 +% rmmod $MOD_KLP_CONVERT_MOD +% modprobe $MOD_KLP_CONVERT2 +livepatch: enabling patch '$MOD_KLP_CONVERT2' +livepatch: '$MOD_KLP_CONVERT2': initializing patching transition +livepatch: '$MOD_KLP_CONVERT2': starting patching transition +livepatch: '$MOD_KLP_CONVERT2': completing patching transition +livepatch: '$MOD_KLP_CONVERT2': patching complete +% modprobe $MOD_KLP_CONVERT_MOD +livepatch: applying patch '$MOD_KLP_CONVERT2' to loading module '$MOD_KLP_CONVERT_MOD' +$MOD_KLP_CONVERT2: saved_command_line (auto): $saved_cmdline +$MOD_KLP_CONVERT2: driver_name, 0: $MOD_KLP_CONVERT_MOD +$MOD_KLP_CONVERT2: test_klp_get_driver_name(), (auto): $MOD_KLP_CONVERT_MOD +$MOD_KLP_CONVERT2: homonym_string, 2: homonym string B +$MOD_KLP_CONVERT2: get_homonym_string(), 2: homonym string B +% echo 0 > /sys/kernel/livepatch/$MOD_KLP_CONVERT2/enabled +livepatch: '$MOD_KLP_CONVERT2': initializing unpatching transition +livepatch: '$MOD_KLP_CONVERT2': starting unpatching transition +livepatch: '$MOD_KLP_CONVERT2': completing unpatching transition +livepatch: '$MOD_KLP_CONVERT2': unpatching complete +% rmmod $MOD_KLP_CONVERT2 +% rmmod $MOD_KLP_CONVERT_MOD" + exit 0 -- 2.39.2