[PATCH 5.10 162/451] hfsplus: fix volume corruption issue for generic/070

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

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

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

From: Viacheslav Dubeyko <slava@dubeyko.com>

[ Upstream commit ed490f36f439b877393c12a2113601e4145a5a56 ]

The xfstests' test-case generic/070 leaves HFS+ volume
in corrupted state:

sudo ./check generic/070
FSTYP -- hfsplus
PLATFORM -- Linux/x86_64 hfsplus-testing-0001 6.17.0-rc1+ #4 SMP PREEMPT_DYNAMIC Wed Oct 1 15:02:44 PDT 2025
MKFS_OPTIONS -- /dev/loop51
MOUNT_OPTIONS -- /dev/loop51 /mnt/scratch

generic/070 _check_generic_filesystem: filesystem on /dev/loop50 is inconsistent
(see xfstests-dev/results//generic/070.full for details)

Ran: generic/070
Failures: generic/070
Failed 1 of 1 tests

sudo fsck.hfsplus -d /dev/loop50
** /dev/loop50
Using cacheBlockSize=32K cacheTotalBlock=1024 cacheSize=32768K.
Executing fsck_hfs (version 540.1-Linux).
** Checking non-journaled HFS Plus Volume.
The volume name is test
** Checking extents overflow file.
Unused node is not erased (node = 1)
** Checking catalog file.
** Checking multi-linked files.
** Checking catalog hierarchy.
** Checking extended attributes file.
** Checking volume bitmap.
** Checking volume information.
Verify Status: VIStat = 0x0000, ABTStat = 0x0000 EBTStat = 0x0004
CBTStat = 0x0000 CatStat = 0x00000000
** Repairing volume.
** Rechecking volume.
** Checking non-journaled HFS Plus Volume.
The volume name is test
** Checking extents overflow file.
** Checking catalog file.
** Checking multi-linked files.
** Checking catalog hierarchy.
** Checking extended attributes file.
** Checking volume bitmap.
** Checking volume information.
** The volume test was repaired successfully.

It is possible to see that fsck.hfsplus detected not
erased and unused node for the case of extents overflow file.
The HFS+ logic has special method that defines if the node
should be erased:

bool hfs_bnode_need_zeroout(struct hfs_btree *tree)
{
	struct super_block *sb = tree->inode->i_sb;
	struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
	const u32 volume_attr = be32_to_cpu(sbi->s_vhdr->attributes);

	return tree->cnid == HFSPLUS_CAT_CNID &&
		volume_attr & HFSPLUS_VOL_UNUSED_NODE_FIX;
}

However, it is possible to see that this method works
only for the case of catalog file. But debugging of the issue
has shown that HFSPLUS_VOL_UNUSED_NODE_FIX attribute has been
requested for the extents overflow file too:

catalog file
kernel: hfsplus: node 4, num_recs 0, flags 0x10
kernel: hfsplus: tree->cnid 4, volume_attr 0x80000800

extents overflow file
kernel: hfsplus: node 1, num_recs 0, flags 0x10
kernel: hfsplus: tree->cnid 3, volume_attr 0x80000800

This patch modifies the hfs_bnode_need_zeroout() by checking
only volume_attr but not the b-tree ID because node zeroing
can be requested for all HFS+ b-tree types.

sudo ./check generic/070
FSTYP         -- hfsplus
PLATFORM      -- Linux/x86_64 hfsplus-testing-0001 6.18.0-rc3+ #79 SMP PREEMPT_DYNAMIC Fri Oct 31 16:07:42 PDT 2025
MKFS_OPTIONS  -- /dev/loop51
MOUNT_OPTIONS -- /dev/loop51 /mnt/scratch

generic/070 33s ...  34s
Ran: generic/070
Passed all 1 tests

Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
cc: Yangtao Li <frank.li@vivo.com>
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/20251101001229.247432-1-slava@dubeyko.com
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/hfsplus/bnode.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/hfsplus/bnode.c b/fs/hfsplus/bnode.c
index e566cea238279..358294726ff17 100644
--- a/fs/hfsplus/bnode.c
+++ b/fs/hfsplus/bnode.c
@@ -717,6 +717,5 @@ bool hfs_bnode_need_zeroout(struct hfs_btree *tree)
 	struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 	const u32 volume_attr = be32_to_cpu(sbi->s_vhdr->attributes);
 
-	return tree->cnid == HFSPLUS_CAT_CNID &&
-		volume_attr & HFSPLUS_VOL_UNUSED_NODE_FIX;
+	return volume_attr & HFSPLUS_VOL_UNUSED_NODE_FIX;
 }
-- 
2.51.0