From 765b8552a200471414e9e92de3e35ceb9e735e61 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Wed, 6 Apr 2022 11:31:09 +0900 Subject: bootconfig: Check the checksum before removing the bootconfig from initrd Check the bootconfig's checksum before removing the bootconfig data from initrd to avoid modifying initrd by mistake. This will also simplifies the get_boot_config_from_initrd() interface. Link: https://lkml.kernel.org/r/164921226891.1090670.16955839243639298134.stgit@devnote2 Cc: Padmanabha Srinivasaiah Cc: Jonathan Corbet Cc: Randy Dunlap Cc: Nick Desaulniers Cc: Sami Tolvanen Cc: Nathan Chancellor Cc: Masahiro Yamada Cc: Linux Kbuild mailing list Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (Google) --- init/main.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index 98182c3c2c4b..266d61bc67b0 100644 --- a/init/main.c +++ b/init/main.c @@ -266,7 +266,7 @@ static int __init loglevel(char *str) early_param("loglevel", loglevel); #ifdef CONFIG_BLK_DEV_INITRD -static void * __init get_boot_config_from_initrd(u32 *_size, u32 *_csum) +static void * __init get_boot_config_from_initrd(u32 *_size) { u32 size, csum; char *data; @@ -300,17 +300,20 @@ found: return NULL; } + if (xbc_calc_checksum(data, size) != csum) { + pr_err("bootconfig checksum failed\n"); + return NULL; + } + /* Remove bootconfig from initramfs/initrd */ initrd_end = (unsigned long)data; if (_size) *_size = size; - if (_csum) - *_csum = csum; return data; } #else -static void * __init get_boot_config_from_initrd(u32 *_size, u32 *_csum) +static void * __init get_boot_config_from_initrd(u32 *_size) { return NULL; } @@ -409,12 +412,12 @@ static void __init setup_boot_config(void) static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; const char *msg; int pos; - u32 size, csum; + u32 size; char *data, *err; int ret; /* Cut out the bootconfig data even if we have no bootconfig option */ - data = get_boot_config_from_initrd(&size, &csum); + data = get_boot_config_from_initrd(&size); strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL, @@ -438,11 +441,6 @@ static void __init setup_boot_config(void) return; } - if (xbc_calc_checksum(data, size) != csum) { - pr_err("bootconfig checksum failed\n"); - return; - } - ret = xbc_init(data, size, &msg, &pos); if (ret < 0) { if (pos < 0) @@ -471,7 +469,7 @@ static void __init exit_boot_config(void) static void __init setup_boot_config(void) { /* Remove bootconfig data from initrd */ - get_boot_config_from_initrd(NULL, NULL); + get_boot_config_from_initrd(NULL); } static int __init warn_bootconfig(char *str) -- cgit v1.2.3 From a2a9d67a26ec94a99ed29efbd61cf5be0a575678 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Wed, 6 Apr 2022 11:31:19 +0900 Subject: bootconfig: Support embedding a bootconfig file in kernel This allows kernel developer to embed a default bootconfig file in the kernel instead of embedding it in the initrd. This will be good for who are using the kernel without initrd, or who needs a default bootconfigs. This needs to set two kconfigs: CONFIG_BOOT_CONFIG_EMBED=y and set the file path to CONFIG_BOOT_CONFIG_EMBED_FILE. Note that you still need 'bootconfig' command line option to load the embedded bootconfig. Also if you boot using an initrd with a different bootconfig, the kernel will use the bootconfig in the initrd, instead of the default bootconfig. Link: https://lkml.kernel.org/r/164921227943.1090670.14035119557571329218.stgit@devnote2 Cc: Padmanabha Srinivasaiah Cc: Jonathan Corbet Cc: Randy Dunlap Cc: Nick Desaulniers Cc: Sami Tolvanen Cc: Nathan Chancellor Cc: Masahiro Yamada Cc: Linux Kbuild mailing list Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (Google) --- MAINTAINERS | 1 + include/linux/bootconfig.h | 10 ++++++++++ init/Kconfig | 21 ++++++++++++++++++++- init/main.c | 22 ++++++++++++---------- lib/.gitignore | 1 + lib/Makefile | 8 ++++++++ lib/bootconfig-data.S | 10 ++++++++++ lib/bootconfig.c | 13 +++++++++++++ 8 files changed, 75 insertions(+), 11 deletions(-) create mode 100644 lib/bootconfig-data.S (limited to 'init/main.c') diff --git a/MAINTAINERS b/MAINTAINERS index b90535d923a0..abc8e6fee21e 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7457,6 +7457,7 @@ S: Maintained F: Documentation/admin-guide/bootconfig.rst F: fs/proc/bootconfig.c F: include/linux/bootconfig.h +F: lib/bootconfig-data.S F: lib/bootconfig.c F: tools/bootconfig/* F: tools/bootconfig/scripts/* diff --git a/include/linux/bootconfig.h b/include/linux/bootconfig.h index a4665c7ab07c..1611f9db878e 100644 --- a/include/linux/bootconfig.h +++ b/include/linux/bootconfig.h @@ -289,4 +289,14 @@ int __init xbc_get_info(int *node_size, size_t *data_size); /* XBC cleanup data structures */ void __init xbc_exit(void); +/* XBC embedded bootconfig data in kernel */ +#ifdef CONFIG_BOOT_CONFIG_EMBED +const char * __init xbc_get_embedded_bootconfig(size_t *size); +#else +static inline const char *xbc_get_embedded_bootconfig(size_t *size) +{ + return NULL; +} +#endif + #endif diff --git a/init/Kconfig b/init/Kconfig index ddcbefe535e9..2462d4ae2dc8 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1351,7 +1351,7 @@ endif config BOOT_CONFIG bool "Boot config support" - select BLK_DEV_INITRD + select BLK_DEV_INITRD if !BOOT_CONFIG_EMBED help Extra boot config allows system admin to pass a config file as complemental extension of kernel cmdline when booting. @@ -1361,6 +1361,25 @@ config BOOT_CONFIG If unsure, say Y. +config BOOT_CONFIG_EMBED + bool "Embed bootconfig file in the kernel" + depends on BOOT_CONFIG + help + Embed a bootconfig file given by BOOT_CONFIG_EMBED_FILE in the + kernel. Usually, the bootconfig file is loaded with the initrd + image. But if the system doesn't support initrd, this option will + help you by embedding a bootconfig file while building the kernel. + + If unsure, say N. + +config BOOT_CONFIG_EMBED_FILE + string "Embedded bootconfig file path" + depends on BOOT_CONFIG_EMBED + help + Specify a bootconfig file which will be embedded to the kernel. + This bootconfig will be used if there is no initrd or no other + bootconfig in the initrd. + choice prompt "Compiler optimization level" default CC_OPTIMIZE_FOR_PERFORMANCE diff --git a/init/main.c b/init/main.c index 266d61bc67b0..f7fe7cbb1df8 100644 --- a/init/main.c +++ b/init/main.c @@ -266,7 +266,7 @@ static int __init loglevel(char *str) early_param("loglevel", loglevel); #ifdef CONFIG_BLK_DEV_INITRD -static void * __init get_boot_config_from_initrd(u32 *_size) +static void * __init get_boot_config_from_initrd(size_t *_size) { u32 size, csum; char *data; @@ -313,7 +313,7 @@ found: return data; } #else -static void * __init get_boot_config_from_initrd(u32 *_size) +static void * __init get_boot_config_from_initrd(size_t *_size) { return NULL; } @@ -410,14 +410,16 @@ static int __init warn_bootconfig(char *str) static void __init setup_boot_config(void) { static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata; - const char *msg; - int pos; - u32 size; - char *data, *err; - int ret; + const char *msg, *data; + int pos, ret; + size_t size; + char *err; /* Cut out the bootconfig data even if we have no bootconfig option */ data = get_boot_config_from_initrd(&size); + /* If there is no bootconfig in initrd, try embedded one. */ + if (!data) + data = xbc_get_embedded_bootconfig(&size); strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE); err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL, @@ -436,8 +438,8 @@ static void __init setup_boot_config(void) } if (size >= XBC_DATA_MAX) { - pr_err("bootconfig size %d greater than max size %d\n", - size, XBC_DATA_MAX); + pr_err("bootconfig size %ld greater than max size %d\n", + (long)size, XBC_DATA_MAX); return; } @@ -450,7 +452,7 @@ static void __init setup_boot_config(void) msg, pos); } else { xbc_get_info(&ret, NULL); - pr_info("Load bootconfig: %d bytes %d nodes\n", size, ret); + pr_info("Load bootconfig: %ld bytes %d nodes\n", (long)size, ret); /* keys starting with "kernel." are passed via cmdline */ extra_command_line = xbc_make_cmdline("kernel"); /* Also, "init." keys are init arguments */ diff --git a/lib/.gitignore b/lib/.gitignore index e5e217b8307b..54596b634ecb 100644 --- a/lib/.gitignore +++ b/lib/.gitignore @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only /crc32table.h /crc64table.h +/default.bconf /gen_crc32table /gen_crc64table /oid_registry_data.c diff --git a/lib/Makefile b/lib/Makefile index 08053df16c7c..95268d6c75b7 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -280,6 +280,14 @@ $(foreach file, $(libfdt_files), \ lib-$(CONFIG_LIBFDT) += $(libfdt_files) obj-$(CONFIG_BOOT_CONFIG) += bootconfig.o +obj-$(CONFIG_BOOT_CONFIG_EMBED) += bootconfig-data.o + +$(obj)/bootconfig-data.o: $(obj)/default.bconf + +targets += default.bconf +filechk_defbconf = cat $(or $(real-prereqs), /dev/null) +$(obj)/default.bconf: $(CONFIG_BOOT_CONFIG_EMBED_FILE) FORCE + $(call filechk,defbconf) obj-$(CONFIG_RBTREE_TEST) += rbtree_test.o obj-$(CONFIG_INTERVAL_TREE_TEST) += interval_tree_test.o diff --git a/lib/bootconfig-data.S b/lib/bootconfig-data.S new file mode 100644 index 000000000000..ef85ba1a82f4 --- /dev/null +++ b/lib/bootconfig-data.S @@ -0,0 +1,10 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Embed default bootconfig in the kernel. + */ + .section .init.rodata, "aw" + .global embedded_bootconfig_data +embedded_bootconfig_data: + .incbin "lib/default.bconf" + .global embedded_bootconfig_data_end +embedded_bootconfig_data_end: diff --git a/lib/bootconfig.c b/lib/bootconfig.c index 74f3201ab8e5..c59d26068a64 100644 --- a/lib/bootconfig.c +++ b/lib/bootconfig.c @@ -12,6 +12,19 @@ #include #include #include + +#ifdef CONFIG_BOOT_CONFIG_EMBED +/* embedded_bootconfig_data is defined in bootconfig-data.S */ +extern __visible const char embedded_bootconfig_data[]; +extern __visible const char embedded_bootconfig_data_end[]; + +const char * __init xbc_get_embedded_bootconfig(size_t *size) +{ + *size = embedded_bootconfig_data_end - embedded_bootconfig_data; + return (*size) ? embedded_bootconfig_data : NULL; +} +#endif + #else /* !__KERNEL__ */ /* * NOTE: This is only for tools/bootconfig, because tools/bootconfig will -- cgit v1.2.3