From: Xiangyu Chen <xiangyu.c...@windriver.com> Signed-off-by: Xiangyu Chen <xiangyu.c...@windriver.com> Signed-off-by: Alexandre Belloni <alexandre.bell...@bootlin.com> (cherry picked from commit 278e1a0f679be813553b014544314041502a586a) Signed-off-by: Steve Sakoman <st...@sakoman.com> --- ...i-chainloader-Use-grub_loader_set_ex.patch | 86 +++++++++ ...ot-Add-API-to-pass-context-to-loader.patch | 168 ++++++++++++++++++ ...hainloader-Simplify-the-loader-state.patch | 129 ++++++++++++++ meta/recipes-bsp/grub/grub2.inc | 3 + 4 files changed, 386 insertions(+) create mode 100644 meta/recipes-bsp/grub/files/CVE-2022-28736-loader-efi-chainloader-Use-grub_loader_set_ex.patch create mode 100644 meta/recipes-bsp/grub/files/commands-boot-Add-API-to-pass-context-to-loader.patch create mode 100644 meta/recipes-bsp/grub/files/loader-efi-chainloader-Simplify-the-loader-state.patch
diff --git a/meta/recipes-bsp/grub/files/CVE-2022-28736-loader-efi-chainloader-Use-grub_loader_set_ex.patch b/meta/recipes-bsp/grub/files/CVE-2022-28736-loader-efi-chainloader-Use-grub_loader_set_ex.patch new file mode 100644 index 0000000000..5741e53f42 --- /dev/null +++ b/meta/recipes-bsp/grub/files/CVE-2022-28736-loader-efi-chainloader-Use-grub_loader_set_ex.patch @@ -0,0 +1,86 @@ +From 04c86e0bb7b58fc2f913f798cdb18934933e532d Mon Sep 17 00:00:00 2001 +From: Chris Coulson <chris.coul...@canonical.com> +Date: Tue, 5 Apr 2022 11:48:58 +0100 +Subject: [PATCH] loader/efi/chainloader: Use grub_loader_set_ex() + +This ports the EFI chainloader to use grub_loader_set_ex() in order to fix +a use-after-free bug that occurs when grub_cmd_chainloader() is executed +more than once before a boot attempt is performed. + +Fixes: CVE-2022-28736 + +Signed-off-by: Chris Coulson <chris.coul...@canonical.com> +Reviewed-by: Daniel Kiper <daniel.ki...@oracle.com> + +Upstream-Status: Backport +CVE: CVE-2022-28736 + +Reference to upstream patch: +https://git.savannah.gnu.org/cgit/grub.git/commit/?id=04c86e0bb7b58fc2f913f798cdb18934933e532d + +Signed-off-by: Xiangyu Chen <xiangyu.c...@windriver.com> +--- + grub-core/loader/efi/chainloader.c | 16 +++++++--------- + 1 file changed, 7 insertions(+), 9 deletions(-) + +diff --git a/grub-core/loader/efi/chainloader.c b/grub-core/loader/efi/chainloader.c +index d1602c89b..7557eb269 100644 +--- a/grub-core/loader/efi/chainloader.c ++++ b/grub-core/loader/efi/chainloader.c +@@ -44,11 +44,10 @@ GRUB_MOD_LICENSE ("GPLv3+"); + + static grub_dl_t my_mod; + +-static grub_efi_handle_t image_handle; +- + static grub_err_t +-grub_chainloader_unload (void) ++grub_chainloader_unload (void *context) + { ++ grub_efi_handle_t image_handle = (grub_efi_handle_t) context; + grub_efi_loaded_image_t *loaded_image; + grub_efi_boot_services_t *b; + +@@ -64,8 +63,9 @@ grub_chainloader_unload (void) + } + + static grub_err_t +-grub_chainloader_boot (void) ++grub_chainloader_boot (void *context) + { ++ grub_efi_handle_t image_handle = (grub_efi_handle_t) context; + grub_efi_boot_services_t *b; + grub_efi_status_t status; + grub_efi_uintn_t exit_data_size; +@@ -225,6 +225,7 @@ grub_cmd_chainloader (grub_command_t cmd __attribute__ ((unused)), + grub_efi_physical_address_t address = 0; + grub_efi_uintn_t pages = 0; + grub_efi_char16_t *cmdline = NULL; ++ grub_efi_handle_t image_handle = NULL; + + if (argc == 0) + return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected")); +@@ -405,7 +406,7 @@ grub_cmd_chainloader (grub_command_t cmd __attribute__ ((unused)), + efi_call_2 (b->free_pages, address, pages); + grub_free (file_path); + +- grub_loader_set (grub_chainloader_boot, grub_chainloader_unload, 0); ++ grub_loader_set_ex (grub_chainloader_boot, grub_chainloader_unload, image_handle, 0); + return 0; + + fail: +@@ -423,10 +424,7 @@ grub_cmd_chainloader (grub_command_t cmd __attribute__ ((unused)), + efi_call_2 (b->free_pages, address, pages); + + if (image_handle != NULL) +- { +- efi_call_1 (b->unload_image, image_handle); +- image_handle = NULL; +- } ++ efi_call_1 (b->unload_image, image_handle); + + grub_dl_unref (my_mod); + +-- +2.34.1 + diff --git a/meta/recipes-bsp/grub/files/commands-boot-Add-API-to-pass-context-to-loader.patch b/meta/recipes-bsp/grub/files/commands-boot-Add-API-to-pass-context-to-loader.patch new file mode 100644 index 0000000000..a2c0530f04 --- /dev/null +++ b/meta/recipes-bsp/grub/files/commands-boot-Add-API-to-pass-context-to-loader.patch @@ -0,0 +1,168 @@ +From 14ceb3b3ff6db664649138442b6562c114dcf56e Mon Sep 17 00:00:00 2001 +From: Chris Coulson <chris.coul...@canonical.com> +Date: Tue, 5 Apr 2022 10:58:28 +0100 +Subject: [PATCH] commands/boot: Add API to pass context to loader + +Loaders rely on global variables for saving context which is consumed +in the boot hook and freed in the unload hook. In the case where a loader +command is executed twice, calling grub_loader_set() a second time executes +the unload hook, but in some cases this runs when the loader's global +context has already been updated, resulting in the updated context being +freed and potential use-after-free bugs when the boot hook is subsequently +called. + +This adds a new API, grub_loader_set_ex(), which allows a loader to specify +context that is passed to its boot and unload hooks. This is an alternative +to requiring that loaders call grub_loader_unset() before mutating their +global context. + +Signed-off-by: Chris Coulson <chris.coul...@canonical.com> +Reviewed-by: Daniel Kiper <daniel.ki...@oracle.com> + +Upstream-Status: Backport + +Reference to upstream patch: +https://git.savannah.gnu.org/cgit/grub.git/commit/?id=14ceb3b3ff6db664649138442b6562c114dcf56e + +Signed-off-by: Xiangyu Chen <xiangyu.c...@windriver.com> +--- + grub-core/commands/boot.c | 66 ++++++++++++++++++++++++++++++++++----- + include/grub/loader.h | 5 +++ + 2 files changed, 63 insertions(+), 8 deletions(-) + +diff --git a/grub-core/commands/boot.c b/grub-core/commands/boot.c +index bbca81e94..61514788e 100644 +--- a/grub-core/commands/boot.c ++++ b/grub-core/commands/boot.c +@@ -27,10 +27,20 @@ + + GRUB_MOD_LICENSE ("GPLv3+"); + +-static grub_err_t (*grub_loader_boot_func) (void); +-static grub_err_t (*grub_loader_unload_func) (void); ++static grub_err_t (*grub_loader_boot_func) (void *context); ++static grub_err_t (*grub_loader_unload_func) (void *context); ++static void *grub_loader_context; + static int grub_loader_flags; + ++struct grub_simple_loader_hooks ++{ ++ grub_err_t (*boot) (void); ++ grub_err_t (*unload) (void); ++}; ++ ++/* Don't heap allocate this to avoid making grub_loader_set() fallible. */ ++static struct grub_simple_loader_hooks simple_loader_hooks; ++ + struct grub_preboot + { + grub_err_t (*preboot_func) (int); +@@ -44,6 +54,29 @@ static int grub_loader_loaded; + static struct grub_preboot *preboots_head = 0, + *preboots_tail = 0; + ++static grub_err_t ++grub_simple_boot_hook (void *context) ++{ ++ struct grub_simple_loader_hooks *hooks; ++ ++ hooks = (struct grub_simple_loader_hooks *) context; ++ return hooks->boot (); ++} ++ ++static grub_err_t ++grub_simple_unload_hook (void *context) ++{ ++ struct grub_simple_loader_hooks *hooks; ++ grub_err_t ret; ++ ++ hooks = (struct grub_simple_loader_hooks *) context; ++ ++ ret = hooks->unload (); ++ grub_memset (hooks, 0, sizeof (*hooks)); ++ ++ return ret; ++} ++ + int + grub_loader_is_loaded (void) + { +@@ -110,28 +143,45 @@ grub_loader_unregister_preboot_hook (struct grub_preboot *hnd) + } + + void +-grub_loader_set (grub_err_t (*boot) (void), +- grub_err_t (*unload) (void), +- int flags) ++grub_loader_set_ex (grub_err_t (*boot) (void *context), ++ grub_err_t (*unload) (void *context), ++ void *context, ++ int flags) + { + if (grub_loader_loaded && grub_loader_unload_func) +- grub_loader_unload_func (); ++ grub_loader_unload_func (grub_loader_context); + + grub_loader_boot_func = boot; + grub_loader_unload_func = unload; ++ grub_loader_context = context; + grub_loader_flags = flags; + + grub_loader_loaded = 1; + } + ++void ++grub_loader_set (grub_err_t (*boot) (void), ++ grub_err_t (*unload) (void), ++ int flags) ++{ ++ grub_loader_set_ex (grub_simple_boot_hook, ++ grub_simple_unload_hook, ++ &simple_loader_hooks, ++ flags); ++ ++ simple_loader_hooks.boot = boot; ++ simple_loader_hooks.unload = unload; ++} ++ + void + grub_loader_unset(void) + { + if (grub_loader_loaded && grub_loader_unload_func) +- grub_loader_unload_func (); ++ grub_loader_unload_func (grub_loader_context); + + grub_loader_boot_func = 0; + grub_loader_unload_func = 0; ++ grub_loader_context = 0; + + grub_loader_loaded = 0; + } +@@ -158,7 +208,7 @@ grub_loader_boot (void) + return err; + } + } +- err = (grub_loader_boot_func) (); ++ err = (grub_loader_boot_func) (grub_loader_context); + + for (cur = preboots_tail; cur; cur = cur->prev) + if (! err) +diff --git a/include/grub/loader.h b/include/grub/loader.h +index b20864282..97f231054 100644 +--- a/include/grub/loader.h ++++ b/include/grub/loader.h +@@ -40,6 +40,11 @@ void EXPORT_FUNC (grub_loader_set) (grub_err_t (*boot) (void), + grub_err_t (*unload) (void), + int flags); + ++void EXPORT_FUNC (grub_loader_set_ex) (grub_err_t (*boot) (void *context), ++ grub_err_t (*unload) (void *context), ++ void *context, ++ int flags); ++ + /* Unset current loader, if any. */ + void EXPORT_FUNC (grub_loader_unset) (void); + +-- +2.34.1 + diff --git a/meta/recipes-bsp/grub/files/loader-efi-chainloader-Simplify-the-loader-state.patch b/meta/recipes-bsp/grub/files/loader-efi-chainloader-Simplify-the-loader-state.patch new file mode 100644 index 0000000000..a43025d425 --- /dev/null +++ b/meta/recipes-bsp/grub/files/loader-efi-chainloader-Simplify-the-loader-state.patch @@ -0,0 +1,129 @@ +From 1469983ebb9674753ad333d37087fb8cb20e1dce Mon Sep 17 00:00:00 2001 +From: Chris Coulson <chris.coul...@canonical.com> +Date: Tue, 5 Apr 2022 10:02:04 +0100 +Subject: [PATCH] loader/efi/chainloader: Simplify the loader state + +The chainloader command retains the source buffer and device path passed +to LoadImage(), requiring the unload hook passed to grub_loader_set() to +free them. It isn't required to retain this state though - they aren't +required by StartImage() or anything else in the boot hook, so clean them +up before grub_cmd_chainloader() finishes. + +Signed-off-by: Chris Coulson <chris.coul...@canonical.com> +Reviewed-by: Daniel Kiper <daniel.ki...@oracle.com> + +Upstream-Status: Backport + +Reference to upstream patch: +https://git.savannah.gnu.org/cgit/grub.git/commit/?id=1469983ebb9674753ad333d37087fb8cb20e1dce + +Signed-off-by: Xiangyu Chen <xiangyu.c...@windriver.com> +--- + grub-core/loader/efi/chainloader.c | 38 +++++++++++++++++------------- + 1 file changed, 21 insertions(+), 17 deletions(-) + +diff --git a/grub-core/loader/efi/chainloader.c b/grub-core/loader/efi/chainloader.c +index 2bd80f4db..d1602c89b 100644 +--- a/grub-core/loader/efi/chainloader.c ++++ b/grub-core/loader/efi/chainloader.c +@@ -44,25 +44,20 @@ GRUB_MOD_LICENSE ("GPLv3+"); + + static grub_dl_t my_mod; + +-static grub_efi_physical_address_t address; +-static grub_efi_uintn_t pages; +-static grub_efi_device_path_t *file_path; + static grub_efi_handle_t image_handle; +-static grub_efi_char16_t *cmdline; + + static grub_err_t + grub_chainloader_unload (void) + { ++ grub_efi_loaded_image_t *loaded_image; + grub_efi_boot_services_t *b; + ++ loaded_image = grub_efi_get_loaded_image (image_handle); ++ if (loaded_image != NULL) ++ grub_free (loaded_image->load_options); ++ + b = grub_efi_system_table->boot_services; + efi_call_1 (b->unload_image, image_handle); +- efi_call_2 (b->free_pages, address, pages); +- +- grub_free (file_path); +- grub_free (cmdline); +- cmdline = 0; +- file_path = 0; + + grub_dl_unref (my_mod); + return GRUB_ERR_NONE; +@@ -140,7 +135,7 @@ make_file_path (grub_efi_device_path_t *dp, const char *filename) + char *dir_start; + char *dir_end; + grub_size_t size; +- grub_efi_device_path_t *d; ++ grub_efi_device_path_t *d, *file_path; + + dir_start = grub_strchr (filename, ')'); + if (! dir_start) +@@ -222,11 +217,14 @@ grub_cmd_chainloader (grub_command_t cmd __attribute__ ((unused)), + grub_efi_status_t status; + grub_efi_boot_services_t *b; + grub_device_t dev = 0; +- grub_efi_device_path_t *dp = 0; ++ grub_efi_device_path_t *dp = NULL, *file_path = NULL; + grub_efi_loaded_image_t *loaded_image; + char *filename; + void *boot_image = 0; + grub_efi_handle_t dev_handle = 0; ++ grub_efi_physical_address_t address = 0; ++ grub_efi_uintn_t pages = 0; ++ grub_efi_char16_t *cmdline = NULL; + + if (argc == 0) + return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected")); +@@ -234,11 +232,6 @@ grub_cmd_chainloader (grub_command_t cmd __attribute__ ((unused)), + + grub_dl_ref (my_mod); + +- /* Initialize some global variables. */ +- address = 0; +- image_handle = 0; +- file_path = 0; +- + b = grub_efi_system_table->boot_services; + + file = grub_file_open (filename, GRUB_FILE_TYPE_EFI_CHAINLOADED_IMAGE); +@@ -408,6 +401,10 @@ grub_cmd_chainloader (grub_command_t cmd __attribute__ ((unused)), + grub_file_close (file); + grub_device_close (dev); + ++ /* We're finished with the source image buffer and file path now. */ ++ efi_call_2 (b->free_pages, address, pages); ++ grub_free (file_path); ++ + grub_loader_set (grub_chainloader_boot, grub_chainloader_unload, 0); + return 0; + +@@ -419,11 +416,18 @@ grub_cmd_chainloader (grub_command_t cmd __attribute__ ((unused)), + if (file) + grub_file_close (file); + ++ grub_free (cmdline); + grub_free (file_path); + + if (address) + efi_call_2 (b->free_pages, address, pages); + ++ if (image_handle != NULL) ++ { ++ efi_call_1 (b->unload_image, image_handle); ++ image_handle = NULL; ++ } ++ + grub_dl_unref (my_mod); + + return grub_errno; +-- +2.34.1 + diff --git a/meta/recipes-bsp/grub/grub2.inc b/meta/recipes-bsp/grub/grub2.inc index 7161c4560b..e819cb9775 100644 --- a/meta/recipes-bsp/grub/grub2.inc +++ b/meta/recipes-bsp/grub/grub2.inc @@ -34,6 +34,9 @@ SRC_URI = "${GNU_MIRROR}/grub/grub-${PV}.tar.gz \ file://CVE-2022-28735-kern-efi-sb-Reject-non-kernel-files-in-the-shim_lock.patch \ file://0001-configure-Remove-obsoleted-malign-jumps-loops-functi.patch \ file://0002-configure-Check-for-falign-jumps-1-beside-falign-loo.patch \ + file://loader-efi-chainloader-Simplify-the-loader-state.patch \ + file://commands-boot-Add-API-to-pass-context-to-loader.patch \ + file://CVE-2022-28736-loader-efi-chainloader-Use-grub_loader_set_ex.patch\ " SRC_URI[sha256sum] = "23b64b4c741569f9426ed2e3d0e6780796fca081bee4c99f62aa3f53ae803f5f" -- 2.25.1
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