From 0343d901cade475b6b92134cd45184316d80039f Mon Sep 17 00:00:00 2001

From: Robert Marshall <rmarshall@redhat.com>

Date: Tue, 13 Dec 2016 18:20:15 -0500

Subject: [PATCH 65/69] Don't assume --make-default just because --set-index

 was passed.

grubby previously made the assumption that every time a new

boot entry gets added using --set-index, it should be the default. Due

to this behavior, it also masked an logic error that prevented the

selection of the proper index in cases where it was necessary to

dynamically pick a new default boot entry, or to keep the existing

default boot entry when its position in the config file moved.

Resolves: rhbz#1285601

---

 grubby.c | 136 ++++++++++++++++++++++++++++++++++++++++++++-------------------

 1 file changed, 96 insertions(+), 40 deletions(-)

diff --git a/grubby.c b/grubby.c

index 3929212..4e872c0 100644

--- a/grubby.c

+++ b/grubby.c

@@ -2596,66 +2596,121 @@ void markRemovedImage(struct grubConfig *cfg, const char *image,

 		entry->skip = 1;

 }

-void setDefaultImage(struct grubConfig *config, int isUserSpecifiedKernelPath,

+void setDefaultImage(struct grubConfig *config, int isAddingBootEntry,

 		     const char *defaultKernelPath, int newBootEntryIsDefault,

-		     const char *prefix, int flags, int newDefaultBootEntryIndex)

+		     const char *prefix, int flags,

+		     int newDefaultBootEntryIndex, int newBootEntryIndex)

 {

-	struct singleEntry *entry, *entry2, *newDefault;

-	int i, j;

+	struct singleEntry *bootEntry, *newDefault;

+	int indexToVerify, firstKernelEntryIndex, currentLookupIndex;

+

+	/* handle the two cases where the user explictly picks the default

+	 * boot entry index as it would exist post-modification */

+	/* Case 1: user chose to make the latest boot entry the default */

 	if (newBootEntryIsDefault) {

-		config->defaultImage = FIRST_ENTRY_INDEX;

+		config->defaultImage = newBootEntryIndex;

 		return;

-	} else if ((newDefaultBootEntryIndex >= 0) && config->cfi->defaultIsIndex) {

-		if (findEntryByIndex(config, newDefaultBootEntryIndex))

+	}

+

+	/* Case 2: user picked an arbitrary index as the default boot entry */

+	if (newDefaultBootEntryIndex >= FIRST_ENTRY_INDEX

+	    && config->cfi->defaultIsIndex) {

+		indexToVerify = newDefaultBootEntryIndex;

+

+		/* user chose to make latest boot entry the default */

+		if (newDefaultBootEntryIndex == newBootEntryIndex) {

+			config->defaultImage = newBootEntryIndex;

+			return;

+		}

+

+		/* the user picks the default index based on the

+		 * order of the bootloader configuration after

+		 * modification; ensure we are checking for the

+		 * existence of the correct entry */

+		if (newBootEntryIndex < newDefaultBootEntryIndex) {

+			if (!config->isModified)

+				indexToVerify--;

+		}

+

+		/* verify the user selected index will exist */

+		if (findEntryByIndex(config, indexToVerify)) {

 			config->defaultImage = newDefaultBootEntryIndex;

-		else

+		} else {

 			config->defaultImage = NO_DEFAULT_ENTRY;

+		}

+

 		return;

-	} else if (defaultKernelPath) {

-		i = 0;

-		if (findEntryByPath(config, defaultKernelPath, prefix, &i)) {

-			config->defaultImage = i;

-		} else {

+	}

+

+	/* handle cases where the index value may shift */

+

+	/* check validity of existing default or first-entry-found

+	   selection */

+	if (defaultKernelPath) {

+		/* user requested first-entry-found */

+		if (!findEntryByPath(config, defaultKernelPath,

+				     prefix, &firstKernelEntryIndex)) {

+			/* don't change default if can't find match */

 			config->defaultImage = NO_DEFAULT_ENTRY;

 			return;

 		}

-	}

-	/* defaultImage now points to what we'd like to use, but before any order 

-	   changes */

-	if ((config->defaultImage == DEFAULT_SAVED) ||

-	    (config->defaultImage == DEFAULT_SAVED_GRUB2))

-		/* default is set to saved, we don't want to change it */

-		return;

+		config->defaultImage = firstKernelEntryIndex;

-	if (config->defaultImage >= FIRST_ENTRY_INDEX)

-		entry = findEntryByIndex(config, config->defaultImage);

-	else

-		entry = NULL;

+		/* this is where we start looking for decrement later */

+		currentLookupIndex = config->defaultImage;

-	if (entry && !entry->skip) {

-		/* we can preserve the default */

-		if (isUserSpecifiedKernelPath)

+		if (isAddingBootEntry && !config->isModified &&

+		    (newBootEntryIndex < config->defaultImage)) {

+			/* increment because new entry added before default */

 			config->defaultImage++;

-

-		/* count the number of entries erased before this one */

-		for (j = 0; j < config->defaultImage; j++) {

-			entry2 = findEntryByIndex(config, j);

-			if (entry2->skip)

-				config->defaultImage--;

 		}

-	} else if (isUserSpecifiedKernelPath) {

-		config->defaultImage = FIRST_ENTRY_INDEX;

 	} else {

-		/* Either we just erased the default (or the default line was bad

-		 * to begin with) and didn't put a new one in. We'll use the first

-		 * valid image. */

+		/* use pre-existing default entry */

+		currentLookupIndex = config->defaultImage;

+

+		if (isAddingBootEntry

+		    && (newBootEntryIndex <= config->defaultImage)) {

+			config->defaultImage++;

+

+			if (config->isModified) {

+				currentLookupIndex++;

+			}

+		}

+	}

+

+	/* sanity check - is this entry index valid? */

+	bootEntry = findEntryByIndex(config, currentLookupIndex);

+

+	if ((bootEntry && bootEntry->skip) || !bootEntry) {

+		/* entry is to be skipped or is invalid */

+		if (isAddingBootEntry) {

+			config->defaultImage = newBootEntryIndex;

+			return;

+		}

 		newDefault =

 		    findTemplate(config, prefix, &config->defaultImage, 1,

 				 flags);

-		if (!newDefault)

+		if (!newDefault) {

 			config->defaultImage = NO_DEFAULT_ENTRY;

+		}

+

+		return;

+	}

+

+	currentLookupIndex--;

+

+	/* decrement index by the total number of entries deleted */

+

+	for (indexToVerify = currentLookupIndex;

+	     indexToVerify >= FIRST_ENTRY_INDEX; indexToVerify--) {

+

+		bootEntry = findEntryByIndex(config, indexToVerify);

+

+		if (bootEntry && bootEntry->skip) {

+			config->defaultImage--;

+		}

 	}

 }

@@ -5300,7 +5355,8 @@ int main(int argc, const char **argv)

 	markRemovedImage(config, removeKernelPath, bootPrefix);

 	markRemovedImage(config, removeMBKernel, bootPrefix);

 	setDefaultImage(config, newKernelPath != NULL, defaultKernel,

-			makeDefault, bootPrefix, flags, defaultIndex);

+			makeDefault, bootPrefix, flags, defaultIndex,

+			newIndex);

 	setFallbackImage(config, newKernelPath != NULL);

 	if (updateImage(config, updateKernelPath, bootPrefix, newKernelArgs,

 			removeArgs, newMBKernelArgs, removeMBKernelArgs))

-- 

2.9.3