From e3111d5222d4fcb7591044558c41d15537fd16b4 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Tue, 4 Apr 2017 17:09:08 +0100 Subject: [PATCH] BACKPORT: efi/libstub: Unify command line param parsing Merge the parsing of the command line carried out in arm-stub.c with the handling in efi_parse_options(). Note that this also fixes the missing handling of CONFIG_CMDLINE_FORCE=y, in which case the builtin command line should supersede the one passed by the firmware. Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: bhe@redhat.com Cc: bhsharma@redhat.com Cc: bp@alien8.de Cc: eugene@hp.com Cc: evgeny.kalugin@intel.com Cc: jhugo@codeaurora.org Cc: leif.lindholm@linaro.org Cc: linux-efi@vger.kernel.org Cc: mark.rutland@arm.com Cc: roy.franz@cavium.com Cc: rruigrok@codeaurora.org Link: http://lkml.kernel.org/r/20170404160910.28115-1-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar (cherry picked from commit 60f38de7a8d4e816100ceafd1b382df52527bd50) Signed-off-by: Greg Hackmann Change-Id: Ibc6c19a166e5532c9be7e34376ce34341f84b5ea --- drivers/firmware/efi/libstub/arm-stub.c | 24 ++++++------------- drivers/firmware/efi/libstub/arm64-stub.c | 4 +--- .../firmware/efi/libstub/efi-stub-helper.c | 13 +++++++++- drivers/firmware/efi/libstub/efistub.h | 2 ++ include/linux/efi.h | 2 +- 5 files changed, 23 insertions(+), 22 deletions(-) diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c index 993aa56755f6..7ec09ea81b94 100644 --- a/drivers/firmware/efi/libstub/arm-stub.c +++ b/drivers/firmware/efi/libstub/arm-stub.c @@ -18,8 +18,6 @@ #include "efistub.h" -bool __nokaslr; - static int efi_get_secureboot(efi_system_table_t *sys_table_arg) { static efi_char16_t const sb_var_name[] = { @@ -268,18 +266,6 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table, goto fail; } - /* check whether 'nokaslr' was passed on the command line */ - if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) { - static const u8 default_cmdline[] = CONFIG_CMDLINE; - const u8 *str, *cmdline = cmdline_ptr; - - if (IS_ENABLED(CONFIG_CMDLINE_FORCE)) - cmdline = default_cmdline; - str = strstr(cmdline, "nokaslr"); - if (str == cmdline || (str > cmdline && *(str - 1) == ' ')) - __nokaslr = true; - } - si = setup_graphics(sys_table); status = handle_kernel_image(sys_table, image_addr, &image_size, @@ -291,9 +277,13 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table, goto fail_free_cmdline; } - status = efi_parse_options(cmdline_ptr); - if (status != EFI_SUCCESS) - pr_efi_err(sys_table, "Failed to parse EFI cmdline options\n"); + if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) || + IS_ENABLED(CONFIG_CMDLINE_FORCE) || + cmdline_size == 0) + efi_parse_options(CONFIG_CMDLINE); + + if (!IS_ENABLED(CONFIG_CMDLINE_FORCE) && cmdline_size > 0) + efi_parse_options(cmdline_ptr); secure_boot = efi_get_secureboot(sys_table); if (secure_boot > 0) diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c index 959d9b8d4845..f7a6970e9abc 100644 --- a/drivers/firmware/efi/libstub/arm64-stub.c +++ b/drivers/firmware/efi/libstub/arm64-stub.c @@ -24,8 +24,6 @@ #include "efistub.h" -extern bool __nokaslr; - efi_status_t check_platform_features(efi_system_table_t *sys_table_arg) { u64 tg; @@ -60,7 +58,7 @@ efi_status_t handle_kernel_image(efi_system_table_t *sys_table_arg, u64 phys_seed = 0; if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) { - if (!__nokaslr) { + if (!nokaslr()) { status = efi_get_random_bytes(sys_table_arg, sizeof(phys_seed), (u8 *)&phys_seed); diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c index aded10662020..2db141c84e76 100644 --- a/drivers/firmware/efi/libstub/efi-stub-helper.c +++ b/drivers/firmware/efi/libstub/efi-stub-helper.c @@ -41,6 +41,13 @@ static unsigned long __chunk_size = EFI_READ_CHUNK_SIZE; #define EFI_ALLOC_ALIGN EFI_PAGE_SIZE #endif +static int __section(.data) __nokaslr; + +int __pure nokaslr(void) +{ + return __nokaslr; +} + #define EFI_MMAP_NR_SLACK_SLOTS 8 struct file_info { @@ -351,10 +358,14 @@ void efi_free(efi_system_table_t *sys_table_arg, unsigned long size, * environments, first in the early boot environment of the EFI boot * stub, and subsequently during the kernel boot. */ -efi_status_t efi_parse_options(char *cmdline) +efi_status_t efi_parse_options(char const *cmdline) { char *str; + str = strstr(cmdline, "nokaslr"); + if (str == cmdline || (str && str > cmdline && *(str - 1) == ' ')) + __nokaslr = 1; + /* * If no EFI parameters were specified on the cmdline we've got * nothing to do. diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index fac67992bede..d0e5acab547f 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -15,6 +15,8 @@ */ #undef __init +extern int __pure nokaslr(void); + void efi_char16_printk(efi_system_table_t *, efi_char16_t *); efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image, diff --git a/include/linux/efi.h b/include/linux/efi.h index cba7177cbec7..5e204a5ab8c4 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1427,7 +1427,7 @@ efi_status_t handle_cmdline_files(efi_system_table_t *sys_table_arg, unsigned long *load_addr, unsigned long *load_size); -efi_status_t efi_parse_options(char *cmdline); +efi_status_t efi_parse_options(char const *cmdline); efi_status_t efi_setup_gop(efi_system_table_t *sys_table_arg, struct screen_info *si, efi_guid_t *proto,