[PATCH AUTOSEL 6.1 05/39] fs/ntfs3: fix deadlock in mark_as_free_ex

From: Sasha Levin
Date: Sun Oct 29 2023 - 18:59:56 EST


From: Konstantin Komarov <almaz.alexandrovich@xxxxxxxxxxxxxxxxxxxx>

[ Upstream commit bfbe5b31caa74ab97f1784fe9ade5f45e0d3de91 ]

Reported-by: syzbot+e94d98936a0ed08bde43@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/ntfs3/fsntfs.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/fs/ntfs3/fsntfs.c b/fs/ntfs3/fsntfs.c
index 4b79232aeb59b..873b1434a9989 100644
--- a/fs/ntfs3/fsntfs.c
+++ b/fs/ntfs3/fsntfs.c
@@ -2421,10 +2421,12 @@ void mark_as_free_ex(struct ntfs_sb_info *sbi, CLST lcn, CLST len, bool trim)
{
CLST end, i, zone_len, zlen;
struct wnd_bitmap *wnd = &sbi->used.bitmap;
+ bool dirty = false;

down_write_nested(&wnd->rw_lock, BITMAP_MUTEX_CLUSTERS);
if (!wnd_is_used(wnd, lcn, len)) {
- ntfs_set_state(sbi, NTFS_DIRTY_ERROR);
+ /* mark volume as dirty out of wnd->rw_lock */
+ dirty = true;

end = lcn + len;
len = 0;
@@ -2478,6 +2480,8 @@ void mark_as_free_ex(struct ntfs_sb_info *sbi, CLST lcn, CLST len, bool trim)

out:
up_write(&wnd->rw_lock);
+ if (dirty)
+ ntfs_set_state(sbi, NTFS_DIRTY_ERROR);
}

/*
--
2.42.0