Store cmdline in BLS snippets instead of using a grubenv variable

The kernel cmdline was stored as a kernelopts variable in the grubenv file
and the BLS snippets used that. But this turned out to be fragile since the
grubenv file could be removed or get corrupted easily.

To prevent the entries to not have a cmdline if the grubenv can't be read,
a fallback variable was set in the GRUB config file. But this still caused
issues since the config needs to be re-generated to change the parameters.

Instead, let's store the cmdline in the BLS snippets. This will make the
configuration more robust, since it will work even without the grubenv
file and the BLS entries will contain all the information needed to boot.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>

0214-10_linux.in-Store-cmdline-in-BLS-snippets-instead-of.patch

@@ -0,0 +1,160 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Javier Martinez Canillas <javierm@redhat.com>
+Date: Wed, 13 May 2020 19:40:10 +0200
+Subject: [PATCH] 10_linux.in: Store cmdline in BLS snippets instead of using a
+ variable
+
+The kernel cmdline was stored as a kernelopts variable in the grubenv file
+and the BLS snippets used that. But this turned out to be fragile since the
+grubenv file could be removed or get corrupted easily.
+
+To prevent the entries to not have a cmdline if the grubenv can't be read,
+a fallback variable was set in the GRUB config file. But this still caused
+issues since the config needs to be re-generated to change the parameters.
+
+Instead, let's store the cmdline in the BLS snippets. This will make the
+configuration more robust, since it will work even without the grubenv
+file and the BLS entries will contain all the information needed to boot.
+
+Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
+---
+ util/grub-switch-to-blscfg.in | 30 ++++++++++--------------------
+ util/grub.d/10_linux.in       | 41 +++++++++++++++++++++++++++++++----------
+ 2 files changed, 41 insertions(+), 30 deletions(-)
+
+diff --git a/util/grub-switch-to-blscfg.in b/util/grub-switch-to-blscfg.in
+index 3333a620c28..cb229126128 100644
+--- a/util/grub-switch-to-blscfg.in
++++ b/util/grub-switch-to-blscfg.in
+@@ -190,7 +190,7 @@ fi
+ mkbls() {
+     local kernelver=$1 && shift
+     local datetime=$1 && shift
+-    local bootprefix=$1 && shift
++    local kernelopts=$1 && shift
+ 
+     local debugname=""
+     local debugid=""
+@@ -209,10 +209,9 @@ mkbls() {
+         cat <<EOF
+ title ${NAME} (${kernelver}) ${VERSION}${debugname}
+ version ${kernelver}${debugid}
+-linux ${bootprefix}/vmlinuz-${kernelver}
+-initrd ${bootprefix}/initramfs-${kernelver}.img
+-options \$kernelopts
+-id ${ID}-${datetime}-${kernelver}
++linux /vmlinuz-${kernelver}
++initrd /initramfs-${kernelver}.img
++options ${kernelopts}
+ grub_users \$grub_users
+ grub_arg --unrestricted
+ grub_class kernel${flavor}
+@@ -236,28 +235,19 @@ copy_bls() {
+ 
+ 	linux_relpath="$("${grub_mkrelpath}" "${linux_path}")"
+ 	bootprefix="${linux_relpath%%"${linux}"}"
++	cmdline="root=${LINUX_ROOT_DEVICE} ro ${GRUB_CMDLINE_LINUX} ${GRUB_CMDLINE_LINUX_DEFAULT}"
+ 
+-	if [ -f "${kernel_dir}/bls.conf" ] ; then
+-            cp -af "${kernel_dir}/bls.conf" "${bls_target}"
+-            if [ -n "${bootprefix}" ]; then
+-		sed -i -e "s,^\(linux[^ \t]*[ \t]\+\).*,\1${bootprefix}${linux},g" "${bls_target}"
+-		sed -i -e "/^initrd/ s,\([ \t]\+\)\([^ \t]\+\),\1${bootprefix}\2,g" "${bls_target}"
+-            fi
+-	else
+-            mkbls "${kernelver}" \
+-		  "$(date -u +%Y%m%d%H%M%S -d "$(stat -c '%y' "${kernel_dir}")")" \
+-		  "${bootprefix}" \
+-		  >"${bls_target}"
+-	fi
++	mkbls "${kernelver}" \
++	      "$(date -u +%Y%m%d%H%M%S -d "$(stat -c '%y' "${kernel_dir}")")" \
++	      "${bootprefix}" "${cmdline}" >"${bls_target}"
+ 
+ 	if [ "x$GRUB_LINUX_MAKE_DEBUG" = "xtrue" ]; then
+             bls_debug="$(echo ${bls_target} | sed -e "s/${kernelver}/${kernelver}~debug/")"
+             cp -aT  "${bls_target}" "${bls_debug}"
+             title="$(grep '^title[ \t]' "${bls_debug}" | sed -e 's/^title[ \t]*//')"
+-            blsid="$(grep '^id[ \t]' "${bls_debug}" | sed -e "s/\.${ARCH}/-debug.${arch}/")"
++            options="$(echo "${cmdline} ${GRUB_CMDLINE_LINUX_DEBUG}" | sed -e 's/\//\\\//g')"
+             sed -i -e "s/^title.*/title ${title}${GRUB_LINUX_DEBUG_TITLE_POSTFIX}/" "${bls_debug}"
+-            sed -i -e "s/^id.*/${blsid}/" "${bls_debug}"
+-            sed -i -e "s/^options.*/options \$kernelopts ${GRUB_CMDLINE_LINUX_DEBUG}/" "${bls_debug}"
++            sed -i -e "s/^options.*/options ${options}/" "${bls_debug}"
+ 	fi
+     done
+ 
+diff --git a/util/grub.d/10_linux.in b/util/grub.d/10_linux.in
+index 09adfce80fd..80299ecaf00 100644
+--- a/util/grub.d/10_linux.in
++++ b/util/grub.d/10_linux.in
+@@ -134,23 +134,43 @@ read_config()
+     done < ${config_file}
+ }
+ 
+-populate_menu()
++blsdir="/boot/loader/entries"
++
++get_sorted_bls()
+ {
+-    blsdir="/boot/loader/entries"
+-    local -a files
+     local IFS=$'\n'
+-    gettext_printf "Generating boot entries from BLS files...\n" >&2
+ 
+-    files=($(for bls in ${blsdir}/*.conf ; do
+-        if ! [[ -e "${bls}" ]] ; then
+-            continue
+-        fi
++    files=($(for bls in ${blsdir}/*.conf; do
+         bls="${bls%.conf}"
+         bls="${bls##*/}"
+         echo "${bls}"
+     done | ${kernel_sort} | tac)) || :
+ 
+-    for bls in "${files[@]}" ; do
++    echo "${files[@]}"
++}
++
++update_bls_cmdline()
++{
++    local cmdline="root=${LINUX_ROOT_DEVICE} ro ${GRUB_CMDLINE_LINUX} ${GRUB_CMDLINE_LINUX_DEFAULT}"
++    local -a files=($(get_sorted_bls))
++
++    for bls in "${files[@]}"; do
++        local options="${cmdline}"
++        if [ -z "${bls##*debug*}" ]; then
++            options="${options} ${GRUB_CMDLINE_LINUX_DEBUG}"
++        fi
++        options="$(echo "${options}" | sed -e 's/\//\\\//g')"
++        sed -i -e "s/^options.*/options ${options}/" "${blsdir}/${bls}.conf"
++    done
++}
++
++populate_menu()
++{
++    local -a files=($(get_sorted_bls))
++
++    gettext_printf "Generating boot entries from BLS files...\n" >&2
++
++    for bls in "${files[@]}"; do
+         read_config "${blsdir}/${bls}.conf"
+ 
+         menu="${menu}menuentry '${title}' ${grub_arg} --id=${bls} {\n"
+@@ -224,6 +244,8 @@ if [ -z "\${kernelopts}" ]; then
+ fi
+ EOF
+ 
++  update_bls_cmdline
++
+   if [ "x${BLS_POPULATE_MENU}" = "xtrue" ]; then
+       populate_menu
+   else
+@@ -244,7 +266,6 @@ EOF
+           fi
+       fi
+ 
+-      ${grub_editenv} - set kernelopts="root=${LINUX_ROOT_DEVICE} ro ${GRUB_CMDLINE_LINUX} ${GRUB_CMDLINE_LINUX_DEFAULT}"
+       if [ -n "${GRUB_EARLY_INITRD_LINUX_CUSTOM}" ]; then
+           ${grub_editenv} - set early_initrd="${GRUB_EARLY_INITRD_LINUX_CUSTOM}"
+       fi

20-grub.install

@@ -24,6 +24,7 @@ BLS_DIR="/boot/loader/entries"
 mkbls() {
     local kernelver=$1 && shift
     local datetime=$1 && shift
+    local kernelopts=$1 && shift
 
     local debugname=""
     local debugid=""
@@ -42,7 +43,7 @@ title ${NAME} (${kernelver}) ${VERSION}${debugname}
 version ${kernelver}${debugid}
 linux /vmlinuz-${kernelver}
 initrd /initramfs-${kernelver}.img
-options \$kernelopts
+options ${kernelopts}
 grub_users \$grub_users
 grub_arg --unrestricted
 grub_class kernel${flavor}
@@ -77,19 +78,29 @@ case "$COMMAND" in
         fi
 
         if [[ "x${GRUB_ENABLE_BLSCFG}" = "xtrue" ]] || [[ ! -f /sbin/new-kernel-pkg ]]; then
+            if [[ -f /etc/kernel/cmdline ]]; then
+                read -r -d '' -a BOOT_OPTIONS < /etc/kernel/cmdline
+            elif [[ -f /usr/lib/kernel/cmdline ]]; then
+                read -r -d '' -a BOOT_OPTIONS < /usr/lib/kernel/cmdline
+            else
+                declare -a BOOT_OPTIONS
+
+                read -r -d '' -a line < /proc/cmdline
+                for i in "${line[@]}"; do
+                    [[ "${i#initrd=*}" != "$i" ]] && continue
+                    [[ "${i#BOOT_IMAGE=*}" != "$i" ]] && continue
+                    BOOT_OPTIONS+=("$i")
+                done
+            fi
+
             eval "$(grub2-get-kernel-settings)" || true
             [[ -d "$BLS_DIR" ]] || mkdir -m 0700 -p "$BLS_DIR"
             BLS_ID="${MACHINE_ID}-${KERNEL_VERSION}"
             BLS_TARGET="${BLS_DIR}/${BLS_ID}.conf"
-            if [[ -f "${KERNEL_DIR}/bls.conf" ]]; then
-                cp -aT "${KERNEL_DIR}/bls.conf" "${BLS_TARGET}" || exit $?
-            else
             mkbls "${KERNEL_VERSION}" \
 		  "$(date -u +%Y%m%d%H%M%S -d "$(stat -c '%y' "${KERNEL_DIR}")")" \
-                    >"${BLS_TARGET}"
+                  "${BOOT_OPTIONS[*]}" >"${BLS_TARGET}"
-            fi
+            command -v restorecon &>/dev/null && restorecon -R "${BLS_TARGET}"
-            command -v restorecon &>/dev/null && \
-                restorecon -R "${BLS_TARGET}"
 
             LINUX="$(grep '^linux[ \t]' "${BLS_TARGET}" | sed -e 's,^linux[ \t]*,,')"
             INITRD="$(grep '^initrd[ \t]' "${BLS_TARGET}" | sed -e 's,^initrd[ \t]*,,')"
@@ -111,14 +122,12 @@ case "$COMMAND" in
             fi
 
             if [ "x$GRUB_LINUX_MAKE_DEBUG" = "xtrue" ]; then
-                ARCH="$(uname -m)"
-                BLS_DEBUG_ID="$(echo ${BLS_ID} | sed -e "s/${KERNEL_VERSION}/${KERNEL_VERSION}~debug/")"
                 BLS_DEBUG="$(echo ${BLS_TARGET} | sed -e "s/${KERNEL_VERSION}/${KERNEL_VERSION}~debug/")"
                 cp -aT  "${BLS_TARGET}" "${BLS_DEBUG}"
                 TITLE="$(grep '^title[ \t]' "${BLS_DEBUG}" | sed -e 's/^title[ \t]*//')"
+                OPTIONS="$(echo "${BOOT_OPTIONS[*]} ${GRUB_CMDLINE_LINUX_DEBUG}" | sed -e 's/\//\\\//g')"
                 sed -i -e "s/^title.*/title ${TITLE}${GRUB_LINUX_DEBUG_TITLE_POSTFIX}/" "${BLS_DEBUG}"
-                sed -i -e "s/^id.*/id ${BLS_DEBUG_ID}/" "${BLS_DEBUG}"
+                sed -i -e "s/^options.*/options ${OPTIONS}/" "${BLS_DEBUG}"
-                sed -i -e "s/^options.*/options \$kernelopts ${GRUB_CMDLINE_LINUX_DEBUG}/" "${BLS_DEBUG}"
                 if [ -n "$NEWDEFAULT" -a "x$GRUB_DEFAULT_TO_DEBUG" = "xtrue" ]; then
                     NEWDEFAULT="${BLS_DEBUG_ID}"
                 fi
@@ -145,7 +154,6 @@ case "$COMMAND" in
     remove)
 
         if [[ "x${GRUB_ENABLE_BLSCFG}" = "xtrue" ]] || [[ ! -f /sbin/new-kernel-pkg ]]; then
-            ARCH="$(uname -m)"
             BLS_TARGET="${BLS_DIR}/${MACHINE_ID}-${KERNEL_VERSION}.conf"
             BLS_DEBUG="$(echo ${BLS_TARGET} | sed -e "s/${KERNEL_VERSION}/${KERNEL_VERSION}~debug/")"
             rm -f "${BLS_TARGET}" "${BLS_DEBUG}"

grub.patches

@@ -211,3 +211,4 @@ Patch0210: 0210-efi-Set-image-base-address-before-jumping-to-the-PE-.patch
 Patch0211: 0211-blscfg-Lookup-default_kernelopts-variable-as-fallbac.patch
 Patch0212: 0212-10_linux.in-fix-early-exit-due-error-when-reading-pe.patch
 Patch0213: 0213-envblk-Fix-buffer-overrun-when-attempting-to-shrink-.patch
+Patch0214: 0214-10_linux.in-Store-cmdline-in-BLS-snippets-instead-of.patch

grub2.spec

@@ -9,7 +9,7 @@
 Name:		grub2
 Epoch:		1
 Version:	2.04
-Release:	16%{?dist}
+Release:	17%{?dist}
 Summary:	Bootloader with support for Linux, Multiboot and more
 License:	GPLv3+
 URL:		http://www.gnu.org/software/grub/
@@ -504,6 +504,9 @@ rm -r /boot/grub2.tmp/ || :
 %endif
 
 %changelog
+* Wed May 13 2020 Javier Martinez Canillas <javierm@redhat.com> - 2.04-17
+- Store cmdline in BLS snippets instead of using a grubenv variable
+
 * Tue May 12 2020 Javier Martinez Canillas <javierm@redhat.com> - 2.04-16
 - Fix a segfault in grub2-editenv when attempting to shrink a variable