From: Theodore Ts'o <tytso@mit.edu>
Date: Fri, 28 Dec 2012 23:26:12 +0000 (-0500)
Subject: mke2fs: fix crash when parsing "-E resize=NNN" with "-O 64bit"
X-Git-Tag: v1.42.7~61
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=49cdefd3312c5ac81ec5d233d62441281ad26e55;p=thirdparty%2Fe2fsprogs.git

mke2fs: fix crash when parsing "-E resize=NNN" with "-O 64bit"

If the 64-bit file system feature is enabled, then mke2fs would crash
due to a divide-by-zero error caused by s_desc_size not being
initialized yet.

Reported-by: George Spelvin <linux@horizon.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---

diff --git a/misc/mke2fs.c b/misc/mke2fs.c
index 7ec8cc2f3..0f9a299ff 100644
--- a/misc/mke2fs.c
+++ b/misc/mke2fs.c
@@ -1873,6 +1873,14 @@ profile_error:
 
 	blocksize = EXT2_BLOCK_SIZE(&fs_param);
 
+	/*
+	 * Initialize s_desc_size so that the parse_extended_opts()
+	 * can correctly handle "-E resize=NNN" if the 64-bit option
+	 * is set.
+	 */
+	if (fs_param.s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT)
+		fs_param.s_desc_size = EXT2_MIN_DESC_SIZE_64BIT;
+
 	/* This check should happen beyond the last assignment to blocksize */
 	if (blocksize > sys_page_size) {
 		if (!force) {