[PATCH 4.9 48/71] ext4: fix EXT4_IOC_GROUP_ADD ioctl

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: ruippan (æç) <ruippan@xxxxxxxxxxx>

commit e647e29196b7f802f8242c39ecb7cc937f5ef217 upstream.

Commit e2b911c53584 ("ext4: clean up feature test macros with
predicate functions") broke the EXT4_IOC_GROUP_ADD ioctl.  This was
not noticed since only very old versions of resize2fs (before
e2fsprogs 1.42) use this ioctl.  However, using a new kernel with an
enterprise Linux userspace will cause attempts to use online resize to
fail with "No reserved GDT blocks".

Fixes: e2b911c53584 ("ext4: clean up feature test macros with predicate...")
Cc: stable@xxxxxxxxxx # v4.4
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: ruippan (æç) <ruippan@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 fs/ext4/resize.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -1600,7 +1600,7 @@ int ext4_group_add(struct super_block *s
 	}
 
 	if (reserved_gdb || gdb_off == 0) {
-		if (ext4_has_feature_resize_inode(sb) ||
+		if (!ext4_has_feature_resize_inode(sb) ||
 		    !le16_to_cpu(es->s_reserved_gdt_blocks)) {
 			ext4_warning(sb,
 				     "No reserved GDT blocks, can't resize");