[PATCH 4.9 073/153] ext4: fix inline data error paths

Greg Kroah-Hartman
2017-03-10T09:21:04Z

From: Theodore Ts'o <tytso@mit.edu>

commit eb5efbcb762aee4b454b04f7115f73ccbcf8f0ef upstream.

The write_end() function must always unlock the page and drop its ref
count, even on an error.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/ext4/inline.c | 9 ++++++++-
fs/ext4/inode.c | 20 +++++++++++++++-----
2 files changed, 23 insertions(+), 6 deletions(-)

--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -933,8 +933,15 @@ int ext4_da_write_inline_data_end(struct
struct page *page)
{
int i_size_changed = 0;
+ int ret;

- copied = ext4_write_inline_data_end(inode, pos, len, copied, page);
+ ret = ext4_write_inline_data_end(inode, pos, len, copied, page);
+ if (ret < 0) {
+ unlock_page(page);
+ put_page(page);
+ return ret;
+ }
+ copied = ret;

/*
* No need to use i_size_read() here, the i_size
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1324,8 +1324,11 @@ static int ext4_write_end(struct file *f
if (ext4_has_inline_data(inode)) {
ret = ext4_write_inline_data_end(inode, pos, len,
copied, page);
- if (ret < 0)
+ if (ret < 0) {
+ unlock_page(page);
+ put_page(page);
goto errout;
+ }
copied = ret;
} else
copied = block_write_end(file, mapping, pos,
@@ -1427,10 +1430,16 @@ static int ext4_journalled_write_end(str

BUG_ON(!ext4_handle_valid(handle));

- if (ext4_has_inline_data(inode))
- copied = ext4_write_inline_data_end(inode, pos, len,
- copied, page);
- else if (unlikely(copied < len) && !PageUptodate(page)) {
+ if (ext4_has_inline_data(inode)) {
+ ret = ext4_write_inline_data_end(inode, pos, len,
+ copied, page);
+ if (ret < 0) {
+ unlock_page(page);
+ put_page(page);
+ goto errout;
+ }
+ copied = ret;
+ } else if (unlikely(copied < len) && !PageUptodate(page)) {
copied = 0;
ext4_journalled_zero_new_buffers(handle, page, from, to);
} else {
@@ -1465,6 +1474,7 @@ static int ext4_journalled_write_end(str
*/
ext4_orphan_add(handle, inode);

+errout:
ret2 = ext4_journal_stop(handle);
if (!ret)
ret = ret2;