From dc5c4e3f52ab2a829168e81bd1e9eafced9b7c09 Mon Sep 17 00:00:00 2001 From: Robbie Harwood Date: Wed, 12 Apr 2023 15:23:39 +0000 Subject: [PATCH] Add switch-root support to grub-emu Signed-off-by: Robbie Harwood --- 0332-emu-Add-switch-root-to-grub-emu.patch | 330 +++++++++++++++++++++ grub.patches | 1 + grub2.spec | 5 +- 3 files changed, 335 insertions(+), 1 deletion(-) create mode 100644 0332-emu-Add-switch-root-to-grub-emu.patch diff --git a/0332-emu-Add-switch-root-to-grub-emu.patch b/0332-emu-Add-switch-root-to-grub-emu.patch new file mode 100644 index 0000000..2a0f34b --- /dev/null +++ b/0332-emu-Add-switch-root-to-grub-emu.patch @@ -0,0 +1,330 @@ +From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 +From: Nicolas Frayer +Date: Fri, 31 Mar 2023 20:47:58 +0200 +Subject: [PATCH] emu: Add switch-root to grub-emu + +If the kernel running grub emu is the same as the one we want to +boot, it makes sense that we just switch-root instead of kexec +the same kernel again by doing grub2-emu --switch-root + +Signed-off-by: Nicolas Frayer +--- + grub-core/kern/emu/main.c | 5 +- + grub-core/kern/emu/misc.c | 13 +++ + grub-core/loader/emu/linux.c | 209 +++++++++++++++++++++++++++++++++++++++++-- + include/grub/emu/exec.h | 2 +- + include/grub/emu/misc.h | 2 + + 5 files changed, 223 insertions(+), 8 deletions(-) + +diff --git a/grub-core/kern/emu/main.c b/grub-core/kern/emu/main.c +index 68e2b283bb..ccb2863f5b 100644 +--- a/grub-core/kern/emu/main.c ++++ b/grub-core/kern/emu/main.c +@@ -108,6 +108,7 @@ static struct argp_option options[] = { + {"verbose", 'v', 0, 0, N_("print verbose messages."), 0}, + {"hold", 'H', N_("SECS"), OPTION_ARG_OPTIONAL, N_("wait until a debugger will attach"), 0}, + {"kexec", 'X', 0, 0, N_("use kexec to boot Linux kernels via systemctl (pass twice to enable dangerous fallback to non-systemctl)."), 0}, ++ {"switch-root", 'W', 0, 0, N_("use switch-root to only switch root filesystem without restarting the kernel."), 0}, + { 0, 0, 0, 0, 0, 0 } + }; + +@@ -168,7 +169,9 @@ argp_parser (int key, char *arg, struct argp_state *state) + case 'X': + grub_util_set_kexecute (); + break; +- ++ case 'W': ++ grub_util_set_switch_root (); ++ break; + case ARGP_KEY_ARG: + { + /* Too many arguments. */ +diff --git a/grub-core/kern/emu/misc.c b/grub-core/kern/emu/misc.c +index 02d27c3440..4b5123ef96 100644 +--- a/grub-core/kern/emu/misc.c ++++ b/grub-core/kern/emu/misc.c +@@ -40,6 +40,7 @@ + + int verbosity; + int kexecute; ++int switchroot = 0; + + void + grub_util_warn (const char *fmt, ...) +@@ -231,3 +232,15 @@ grub_util_get_kexecute (void) + { + return kexecute; + } ++ ++void ++grub_util_set_switch_root (void) ++{ ++ switchroot = 1; ++} ++ ++int ++grub_util_get_switch_root (void) ++{ ++ return switchroot; ++} +diff --git a/grub-core/loader/emu/linux.c b/grub-core/loader/emu/linux.c +index 7de3f7f861..6feb0412c5 100644 +--- a/grub-core/loader/emu/linux.c ++++ b/grub-core/loader/emu/linux.c +@@ -15,7 +15,6 @@ + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see . + */ +- + #include + #include + #include +@@ -33,6 +32,196 @@ static char *kernel_path; + static char *initrd_path; + static char *boot_cmdline; + ++static grub_err_t ++grub_switch_root (void) ++{ ++ char *tmp = NULL; ++ char *options_cmd = NULL; ++ char *options = NULL; ++ char *subvol = NULL; ++ char *root_uuid = NULL; ++ char *kernel_release = NULL; ++ grub_err_t rc = GRUB_ERR_NONE; ++ const char *subvol_param = "subvol="; ++ const char *kernel_release_prefix = "/boot/vmlinuz-"; ++ const char *root_prefix = "root="; ++ const char *systemctl[] = {"systemctl", "--force", "switch-root", "/sysroot", NULL}; ++ const char *mountrootfs[] = {"mount", root_uuid, "/sysroot", options_cmd, options, NULL}; ++ const char *unamer[] = {"uname", "-r", NULL}; ++ char *uname_buf = NULL; ++ int i = 0; ++ ++ /* Extract the kernel release tag from kernel_path */ ++ if (!kernel_path) ++ { ++ rc = GRUB_ERR_BAD_ARGUMENT; ++ grub_dprintf ("linux", "switch_root: No kernel_path found\n"); ++ goto out; ++ } ++ ++ if ((kernel_release = grub_xasprintf ("%s", (kernel_path + grub_strlen (kernel_release_prefix)))) == NULL) ++ { ++ grub_dprintf ("linux", "switch_root: Failed to allocate memory\n"); ++ rc = GRUB_ERR_BAD_ARGUMENT; ++ goto out; ++ } ++ ++ ++ /* Check for kernel mismatch */ ++ /* Retrieve the current kernel relase tag */ ++ grub_util_exec_redirect (unamer, NULL, "/tmp/version"); ++ ++ grub_file_t f = grub_file_open ("/tmp/version", GRUB_FILE_TYPE_FS_SEARCH); ++ ++ if (f == NULL) ++ { ++ grub_dprintf ("linux", "failed opening file.\n"); ++ rc = GRUB_ERR_FILE_NOT_FOUND; ++ goto out; ++ } ++ ++ if ((uname_buf = grub_malloc (f->size)) == NULL) ++ { ++ grub_dprintf ("linux", "switch_root: Failed to allocate memory\n"); ++ rc = GRUB_ERR_OUT_OF_MEMORY; ++ goto out; ++ } ++ ++ if (grub_file_read (f, uname_buf, f->size) < 0) ++ { ++ grub_dprintf ("linux", "switch_root: failed to read from file\n"); ++ rc = GRUB_ERR_FILE_READ_ERROR; ++ goto out; ++ } ++ ++ grub_file_close (f); ++ ++ if (grub_strstr (uname_buf, kernel_release) == NULL) ++ { ++ grub_dprintf ("linux", "switch_root: kernel mismatch, not performing switch-root ...\n"); ++ rc = GRUB_ERR_NO_KERNEL; ++ goto out; ++ } ++ ++ /* Extract the root partition from boot_cmdline */ ++ if (!boot_cmdline) ++ { ++ rc = GRUB_ERR_BAD_ARGUMENT; ++ goto out; ++ } ++ ++ tmp = grub_strdup (boot_cmdline); ++ ++ if (tmp == NULL) ++ { ++ rc = GRUB_ERR_OUT_OF_MEMORY; ++ goto out; ++ } ++ ++ if ((root_uuid = grub_strstr (tmp, root_prefix)) == NULL) ++ { ++ rc = GRUB_ERR_BAD_ARGUMENT; ++ grub_dprintf ("linux", "switch_root: Can't find rootfs\n"); ++ goto out; ++ } ++ ++ root_uuid += grub_strlen (root_prefix); ++ ++ while (root_uuid[i] != ' ' && root_uuid[i] != '\0') ++ i++; ++ ++ root_uuid[i] = '\0'; ++ ++ /* Allocate a new buffer holding root_uuid */ ++ root_uuid = grub_xasprintf ("%s", root_uuid); ++ ++ if (root_uuid == NULL) ++ { ++ grub_dprintf ("linux", "switch_root: Failed to allocated memory\n"); ++ rc = GRUB_ERR_OUT_OF_MEMORY; ++ goto out; ++ } ++ ++ /* Check for subvol parameter */ ++ grub_strcpy (tmp, boot_cmdline); ++ ++ if ((subvol = grub_strstr(tmp, subvol_param)) != NULL) ++ { ++ i = 0; ++ ++ while (subvol[i] != ' ' && subvol[i] != '\0') ++ i++; ++ ++ subvol[i] = '\0'; ++ ++ /* Allocate a new buffer holding subvol */ ++ subvol = grub_xasprintf("%s", subvol); ++ ++ if (subvol == NULL) ++ { ++ grub_dprintf ("linux", "switch_root: Failed to allocated memory\n"); ++ rc = GRUB_ERR_OUT_OF_MEMORY; ++ goto out; ++ } ++ ++ options_cmd = grub_xasprintf("%s", "-o"); ++ options = grub_xasprintf("%s", subvol); ++ } ++ ++ if (options == NULL) ++ { ++ mountrootfs[3] = NULL; ++ } ++ else ++ { ++ mountrootfs[3] = options_cmd; ++ mountrootfs[4] = options; ++ } ++ ++ mountrootfs[1] = root_uuid; ++ ++ grub_dprintf ("linux", "Executing:\n"); ++ grub_dprintf ("linux", "%s %s %s %s %s\n", mountrootfs[0], mountrootfs[1], ++ mountrootfs[2], mountrootfs[3], mountrootfs[4]); ++ ++ /* Mount the rootfs */ ++ rc = grub_util_exec (mountrootfs); ++ ++ if (rc != GRUB_ERR_NONE) ++ { ++ grub_dprintf ("linux", "switch_root: Failed.\n"); ++ rc = GRUB_ERR_INVALID_COMMAND; ++ goto out; ++ } ++ ++ grub_dprintf ("linux", "Done.\n"); ++ ++ grub_dprintf ("linux", "%s %s %s %s\n", systemctl[0], systemctl[1], ++ systemctl[2], systemctl[3]); ++ ++ /* Switch root */ ++ rc = grub_util_exec (systemctl); ++ ++ if (rc != GRUB_ERR_NONE) ++ { ++ grub_dprintf ("linux", "switch_root: Failed.\n"); ++ rc = GRUB_ERR_INVALID_COMMAND; ++ goto out; ++ } ++ ++ grub_dprintf ("linux", "Done.\n"); ++ ++out: ++ grub_free (tmp); ++ grub_free (options_cmd); ++ grub_free (options); ++ grub_free (subvol); ++ grub_free (root_uuid); ++ grub_free (uname_buf); ++ grub_free (kernel_release); ++ return rc; ++} ++ + static grub_err_t + grub_linux_boot (void) + { +@@ -51,12 +240,20 @@ grub_linux_boot (void) + else + initrd_param = grub_xasprintf ("%s", ""); + +- grub_dprintf ("linux", "%serforming 'kexec -la %s %s %s'\n", +- (kexecute) ? "P" : "Not p", +- kernel_path, initrd_param, boot_cmdline); ++ if (grub_util_get_switch_root() == 1) ++ { ++ rc = grub_switch_root(); ++ if (rc != GRUB_ERR_NONE) ++ grub_fatal (N_("Failed to execute switch_root\n")); ++ } ++ else if (kexecute) ++ { ++ grub_dprintf ("linux", "%serforming 'kexec -la %s %s %s'\n", ++ (kexecute) ? "P" : "Not p", ++ kernel_path, initrd_param, boot_cmdline); + +- if (kexecute) +- rc = grub_util_exec (kexec); ++ rc = grub_util_exec (kexec); ++ } + + grub_free (initrd_param); + +diff --git a/include/grub/emu/exec.h b/include/grub/emu/exec.h +index 1b61b4a2e5..e82f13215e 100644 +--- a/include/grub/emu/exec.h ++++ b/include/grub/emu/exec.h +@@ -36,7 +36,7 @@ grub_util_exec_redirect_all (const char *const *argv, const char *stdin_file, + int + EXPORT_FUNC(grub_util_exec) (const char *const *argv); + int +-grub_util_exec_redirect (const char *const *argv, const char *stdin_file, ++EXPORT_FUNC(grub_util_exec_redirect) (const char *const *argv, const char *stdin_file, + const char *stdout_file); + int + grub_util_exec_redirect_null (const char *const *argv); +diff --git a/include/grub/emu/misc.h b/include/grub/emu/misc.h +index 01056954b9..f3a712a8b2 100644 +--- a/include/grub/emu/misc.h ++++ b/include/grub/emu/misc.h +@@ -59,6 +59,8 @@ void EXPORT_FUNC(grub_util_error) (const char *fmt, ...) __attribute__ ((format + + void EXPORT_FUNC(grub_util_set_kexecute) (void); + int EXPORT_FUNC(grub_util_get_kexecute) (void) WARN_UNUSED_RESULT; ++void EXPORT_FUNC(grub_util_set_switch_root) (void); ++int EXPORT_FUNC(grub_util_get_switch_root) (void); + + grub_uint64_t EXPORT_FUNC (grub_util_get_cpu_time_ms) (void); + diff --git a/grub.patches b/grub.patches index 0781c1b..18e904a 100644 --- a/grub.patches +++ b/grub.patches @@ -329,3 +329,4 @@ Patch0328: 0328-tpm-Disable-the-tpm-verifier-if-the-TPM-device-is-no.patch Patch0329: 0329-grub_dl_set_mem_attrs-fix-format-string.patch Patch0330: 0330-grub_dl_set_mem_attrs-add-self-check-for-the-tramp-G.patch Patch0331: 0331-grub_dl_load_segments-page-align-the-tramp-GOT-areas.patch +Patch0332: 0332-emu-Add-switch-root-to-grub-emu.patch diff --git a/grub2.spec b/grub2.spec index 34fdfe3..aba7d63 100644 --- a/grub2.spec +++ b/grub2.spec @@ -17,7 +17,7 @@ Name: grub2 Epoch: 1 Version: 2.06 -Release: 94%{?dist} +Release: 95%{?dist} Summary: Bootloader with support for Linux, Multiboot and more License: GPLv3+ URL: http://www.gnu.org/software/grub/ @@ -544,6 +544,9 @@ mv ${EFI_HOME}/grub.cfg.stb ${EFI_HOME}/grub.cfg %endif %changelog +* Wed Apr 12 2023 Robbie Harwood - 2.06-95 +- Add switch-root support to grub-emu + * Mon Apr 10 2023 Robbie Harwood - 2.06-94 - Fix aa64 page fault with EFI_MEMORY_ATTRIBUTE_PROTOCOL