Message ID | cff4953b5c9306aba71e944ab176a5d396b9a1b7.1709182250.git.ritesh.list@gmail.com |
---|---|
State | New |
Headers | show |
Series | [1/2] ext4: Fixes len calculation in mpage_journal_page_buffers | expand |
On Thu 29-02-24 11:40:13, Ritesh Harjani (IBM) wrote: > Truncate operation can race with writeback, in which inode->i_size can get > truncated and therefore size - folio_pos() can be negative. This fixes the > len calculation. However this path doesn't get easily triggered even > with data journaling. > > Cc: <stable@kernel.org> # v6.5 > Fixes: 80be8c5cc925 ("Fixes: ext4: Make mpage_journal_page_buffers use folio") > Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Looks good. Feel free to add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > --- > fs/ext4/inode.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index 537803250ca9..bab9223d94ac 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -2334,7 +2334,7 @@ static int mpage_journal_page_buffers(handle_t *handle, > > if (folio_pos(folio) + len > size && > !ext4_verity_in_progress(inode)) > - len = size - folio_pos(folio); > + len = size & (len - 1); > > return ext4_journal_folio_buffers(handle, folio, len); > } > -- > 2.39.2 >
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 537803250ca9..bab9223d94ac 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2334,7 +2334,7 @@ static int mpage_journal_page_buffers(handle_t *handle, if (folio_pos(folio) + len > size && !ext4_verity_in_progress(inode)) - len = size - folio_pos(folio); + len = size & (len - 1); return ext4_journal_folio_buffers(handle, folio, len); }
Truncate operation can race with writeback, in which inode->i_size can get truncated and therefore size - folio_pos() can be negative. This fixes the len calculation. However this path doesn't get easily triggered even with data journaling. Cc: <stable@kernel.org> # v6.5 Fixes: 80be8c5cc925 ("Fixes: ext4: Make mpage_journal_page_buffers use folio") Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> --- fs/ext4/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)