From e9d972c483d98b6b6fc9251166a1f5c2ca37ac5e Mon Sep 17 00:00:00 2001
From: Lukas Czerner <lczerner@redhat.com>
Date: Wed, 8 Aug 2018 13:52:56 +0200
Subject: [PATCH 06/16] e2fsck: remove resize inode if both resize_inode and
 meta_bg are enabled

commit 74848259f0dd42bd478f0541c94f31ccd68eac3c

Previous e2fsprogs versions allowed to create a file system with both
resize_inode and meta_bg enabled. This was fixed by upstream commit
42e77d5d ("libext2fs: don't create filesystems with meta_bg and resize_inode")

However e2fsck still does not recognize the conflict and will attempt to
clear and recreate resize_inode if it's corrupted due to this incompatible
feature combination, though it will create it in the same wrong layout.

Fix it by teaching e2fsck to recognize resize_inode and meta_bg
conflict and fixing it by disabling and clearing resize inode.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---
 e2fsck/problem.c | 6 ++++++
 e2fsck/problem.h | 3 +++
 e2fsck/super.c   | 8 ++++++++
 3 files changed, 17 insertions(+)

diff --git a/e2fsck/problem.c b/e2fsck/problem.c
index 83584a08..a01b2560 100644
--- a/e2fsck/problem.c
+++ b/e2fsck/problem.c
@@ -438,6 +438,12 @@ static struct e2fsck_problem problem_table[] = {
 	  N_("@S 64bit filesystems needs extents to access the whole disk.  "),
 	  PROMPT_FIX, PR_PREEN_OK | PR_NO_OK},
 
+	/* Meta_bg and resize_inode are not compatible, disable resize_inode*/
+	{ PR_0_DISABLE_RESIZE_INODE,
+	  N_("Resize_@i and meta_bg features are enabled. Those features are\n"
+	     "not compatible. Resize @i should be disabled.  "),
+	  PROMPT_FIX, 0 },
+
 	/* Pass 1 errors */
 
 	/* Pass 1: Checking inodes, blocks, and sizes */
diff --git a/e2fsck/problem.h b/e2fsck/problem.h
index 6cb09cfb..cf2df8ce 100644
--- a/e2fsck/problem.h
+++ b/e2fsck/problem.h
@@ -252,6 +252,9 @@ struct problem_context {
 /* 64bit is set but extents are not set. */
 #define PR_0_64BIT_WITHOUT_EXTENTS		0x000048
 
+/* Meta_bg and resize_inode are not compatible, remove resize_inode*/
+#define PR_0_DISABLE_RESIZE_INODE		0x000051
+
 /*
  * Pass 1 errors
  */
diff --git a/e2fsck/super.c b/e2fsck/super.c
index a6be3c69..7e2c2e4f 100644
--- a/e2fsck/super.c
+++ b/e2fsck/super.c
@@ -326,6 +326,14 @@ void check_resize_inode(e2fsck_t ctx)
 
 	clear_problem_context(&pctx);
 
+	if (fs->super->s_feature_compat & EXT2_FEATURE_COMPAT_RESIZE_INODE &&
+	    fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG &&
+	    fix_problem(ctx, PR_0_DISABLE_RESIZE_INODE, &pctx)) {
+		fs->super->s_feature_compat &= ~EXT2_FEATURE_COMPAT_RESIZE_INODE;
+		fs->super->s_reserved_gdt_blocks = 0;
+		ext2fs_mark_super_dirty(fs);
+	}
+
 	/*
 	 * If the resize inode feature isn't set, then
 	 * s_reserved_gdt_blocks must be zero.
-- 
2.20.1