[PATCH v3 2/8] jffs2: wbuf: fix space accounting in recovery secondary write failure

[zhouminqiang]

In jffs2_wbuf_recover(), when the recovery write to the new erase block
also fails, the code marks the already-written portion as REF_OBSOLETE
via jffs2_add_physical_node_ref(). However, the length passed is
ref_totlen(c, jeb, first_raw), which is the length of a single node on
the old block, not retlen which is the actual number of bytes written to
the new block.

When the recovery buffer contains multiple nodes, ref_totlen only
accounts for the first node's length, which can be much smaller than
retlen. This under-deducts free_size, causing subsequent allocations to
land on already-programmed NAND pages and silently corrupt data. When
first_raw is the only node in the recovery range, ref_totlen equals the
full unaligned data size and exceeds the page-aligned retlen,
over-deducting free_size and wasting space.

Use retlen so the new block's free_size accurately reflects which NAND
pages have been programmed.

Signed-off-by: zhouminqiang <zhouminqiang2@xxxxxxxxxx>
---
 fs/jffs2/wbuf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/jffs2/wbuf.c b/fs/jffs2/wbuf.c
index 61e3dbd4cd7b..360a291d9fd5 100644
--- a/fs/jffs2/wbuf.c
+++ b/fs/jffs2/wbuf.c
@@ -437,7 +437,7 @@ static void jffs2_wbuf_recover(struct jffs2_sb_info *c)
 			kfree(buf);
 
 			if (retlen)
-				jffs2_add_physical_node_ref(c, ofs | REF_OBSOLETE, ref_totlen(c, jeb, first_raw), NULL);
+				jffs2_add_physical_node_ref(c, ofs | REF_OBSOLETE, retlen, NULL);
 
 			c->wbuf_len = 0;
 			return;
-- 
2.52.0