From 91b8ca8b26729b729dda8a4eddb9aceaea706f37 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 9 Jul 2025 10:48:32 +0200 Subject: [PATCH] ext4: Make sure BH_New bit is cleared in ->write_end handler Currently we clear BH_New bit in case of error and also in the standard ext4_write_end() handler (in block_commit_write()). However ext4_journalled_write_end() misses this clearing and thus we are leaving stale BH_New bits behind. Generally ext4_block_write_begin() clears these bits before any harm can be done but in case blocksize < pagesize and we hit some error when processing a page with these stale bits, we'll try to zero buffers with these stale BH_New bits and jbd2 will complain (as buffers were not prepared for writing in this transaction). Fix the problem by clearing BH_New bits in ext4_journalled_write_end() and WARN if ext4_block_write_begin() sees stale BH_New bits. Reported-by: Baolin Liu Reported-by: Zhi Long Fixes: 3910b513fcdf ("ext4: persist the new uptodate buffers in ext4_journalled_zero_new_buffers") Signed-off-by: Jan Kara Link: https://patch.msgid.link/20250709084831.23876-2-jack@suse.cz Signed-off-by: Theodore Ts'o --- fs/ext4/inline.c | 2 ++ fs/ext4/inode.c | 3 ++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c index d5b32d242495a..121279f84bef3 100644 --- a/fs/ext4/inline.c +++ b/fs/ext4/inline.c @@ -612,6 +612,7 @@ retry: } else ret = ext4_block_write_begin(handle, folio, from, to, ext4_get_block); + clear_buffer_new(folio_buffers(folio)); if (!ret && ext4_should_journal_data(inode)) { ret = ext4_walk_page_buffers(handle, inode, @@ -891,6 +892,7 @@ static int ext4_da_convert_inline_data_to_extent(struct address_space *mapping, return ret; } + clear_buffer_new(folio_buffers(folio)); folio_mark_dirty(folio); folio_mark_uptodate(folio); ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA); diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 8bdf2029ebc74..eeccb6f588f99 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1189,7 +1189,7 @@ int ext4_block_write_begin(handle_t *handle, struct folio *folio, } continue; } - if (buffer_new(bh)) + if (WARN_ON_ONCE(buffer_new(bh))) clear_buffer_new(bh); if (!buffer_mapped(bh)) { WARN_ON(bh->b_size != blocksize); @@ -1417,6 +1417,7 @@ static int write_end_fn(handle_t *handle, struct inode *inode, ret = ext4_dirty_journalled_data(handle, bh); clear_buffer_meta(bh); clear_buffer_prio(bh); + clear_buffer_new(bh); return ret; } -- 2.47.2