[PATCH 3.10 008/268] ext4: fix fencepost in s_first_meta_bg validation
From: Willy Tarreau <w@1wt.eu>
Date: 2017-06-19 19:32:33
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Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
From: Theodore Ts'o <tytso@mit.edu> commit 2ba3e6e8afc9b6188b471f27cf2b5e3cf34e7af2 upstream. It is OK for s_first_meta_bg to be equal to the number of block group descriptor blocks. (It rarely happens, but it shouldn't cause any problems.) https://bugzilla.kernel.org/show_bug.cgi?id=194567 Fixes: 3a4b77cd47bb837b8557595ec7425f281f2ca1fe Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Willy Tarreau <w@1wt.eu> --- fs/ext4/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index b44dc28..ae1d5c4 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c@@ -3778,7 +3778,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) / EXT4_DESC_PER_BLOCK(sb); if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG)) { - if (le32_to_cpu(es->s_first_meta_bg) >= db_count) { + if (le32_to_cpu(es->s_first_meta_bg) > db_count) { ext4_msg(sb, KERN_WARNING, "first meta block group too large: %u " "(group descriptor block count %u)",
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2.8.0.rc2.1.gbe9624a