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Message-Id: <20180710172840.4309-1-tytso@mit.edu>
Date: Tue, 10 Jul 2018 13:28:40 -0400
From: Theodore Ts'o <tytso@....edu>
To: Ext4 Developers List <linux-ext4@...r.kernel.org>
Cc: Theodore Ts'o <tytso@....edu>, stable@...r.kernel.org
Subject: [PATCH] ext4: fix inline data updates with checksums enabled
The inline data code was updating the raw inode directly; this is
problematic since if metadata checksums are enabled,
ext4_mark_inode_dirty() must be called to update the inode's checksum.
In addition, the jbd2 layer requires that get_write_access() be called
before the metadata buffer is modified. Fix both of these problems.
https://bugzilla.kernel.org/show_bug.cgi?id=200443
Signed-off-by: Theodore Ts'o <tytso@....edu>
Cc: stable@...r.kernel.org
---
fs/ext4/inline.c | 19 +++++++++++--------
fs/ext4/inode.c | 16 +++++++---------
2 files changed, 18 insertions(+), 17 deletions(-)
diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index e55a8bc870bd..3543fe80a3c4 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -682,6 +682,10 @@ int ext4_try_to_write_inline_data(struct address_space *mapping,
goto convert;
}
+ ret = ext4_journal_get_write_access(handle, iloc.bh);
+ if (ret)
+ goto out;
+
flags |= AOP_FLAG_NOFS;
page = grab_cache_page_write_begin(mapping, 0, flags);
@@ -710,7 +714,7 @@ int ext4_try_to_write_inline_data(struct address_space *mapping,
out_up_read:
up_read(&EXT4_I(inode)->xattr_sem);
out:
- if (handle)
+ if (handle && (ret != 1))
ext4_journal_stop(handle);
brelse(iloc.bh);
return ret;
@@ -752,6 +756,7 @@ int ext4_write_inline_data_end(struct inode *inode, loff_t pos, unsigned len,
ext4_write_unlock_xattr(inode, &no_expand);
brelse(iloc.bh);
+ mark_inode_dirty(inode);
out:
return copied;
}
@@ -898,7 +903,6 @@ int ext4_da_write_inline_data_begin(struct address_space *mapping,
goto out;
}
-
page = grab_cache_page_write_begin(mapping, 0, flags);
if (!page) {
ret = -ENOMEM;
@@ -916,6 +920,9 @@ int ext4_da_write_inline_data_begin(struct address_space *mapping,
if (ret < 0)
goto out_release_page;
}
+ ret = ext4_journal_get_write_access(handle, iloc.bh);
+ if (ret)
+ goto out_release_page;
up_read(&EXT4_I(inode)->xattr_sem);
*pagep = page;
@@ -936,7 +943,6 @@ int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
unsigned len, unsigned copied,
struct page *page)
{
- int i_size_changed = 0;
int ret;
ret = ext4_write_inline_data_end(inode, pos, len, copied, page);
@@ -954,10 +960,8 @@ int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
* But it's important to update i_size while still holding page lock:
* page writeout could otherwise come in and zero beyond i_size.
*/
- if (pos+copied > inode->i_size) {
+ if (pos+copied > inode->i_size)
i_size_write(inode, pos+copied);
- i_size_changed = 1;
- }
unlock_page(page);
put_page(page);
@@ -967,8 +971,7 @@ int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
* ordering of page lock and transaction start for journaling
* filesystems.
*/
- if (i_size_changed)
- mark_inode_dirty(inode);
+ mark_inode_dirty(inode);
return copied;
}
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 7d6c10017bdf..4efe77286ecd 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1389,9 +1389,10 @@ static int ext4_write_end(struct file *file,
loff_t old_size = inode->i_size;
int ret = 0, ret2;
int i_size_changed = 0;
+ int inline_data = ext4_has_inline_data(inode);
trace_ext4_write_end(inode, pos, len, copied);
- if (ext4_has_inline_data(inode)) {
+ if (inline_data) {
ret = ext4_write_inline_data_end(inode, pos, len,
copied, page);
if (ret < 0) {
@@ -1419,7 +1420,7 @@ static int ext4_write_end(struct file *file,
* ordering of page lock and transaction start for journaling
* filesystems.
*/
- if (i_size_changed)
+ if (i_size_changed || inline_data)
ext4_mark_inode_dirty(handle, inode);
if (pos + len > inode->i_size && ext4_can_truncate(inode))
@@ -1493,6 +1494,7 @@ static int ext4_journalled_write_end(struct file *file,
int partial = 0;
unsigned from, to;
int size_changed = 0;
+ int inline_data = ext4_has_inline_data(inode);
trace_ext4_journalled_write_end(inode, pos, len, copied);
from = pos & (PAGE_SIZE - 1);
@@ -1500,7 +1502,7 @@ static int ext4_journalled_write_end(struct file *file,
BUG_ON(!ext4_handle_valid(handle));
- if (ext4_has_inline_data(inode)) {
+ if (inline_data) {
ret = ext4_write_inline_data_end(inode, pos, len,
copied, page);
if (ret < 0) {
@@ -1531,7 +1533,7 @@ static int ext4_journalled_write_end(struct file *file,
if (old_size < pos)
pagecache_isize_extended(inode, old_size, pos);
- if (size_changed) {
+ if (size_changed || inline_data) {
ret2 = ext4_mark_inode_dirty(handle, inode);
if (!ret)
ret = ret2;
@@ -2028,11 +2030,7 @@ static int __ext4_journalled_writepage(struct page *page,
}
if (inline_data) {
- BUFFER_TRACE(inode_bh, "get write access");
- ret = ext4_journal_get_write_access(handle, inode_bh);
-
- err = ext4_handle_dirty_metadata(handle, inode, inode_bh);
-
+ ret = ext4_mark_inode_dirty(handle, inode);
} else {
ret = ext4_walk_page_buffers(handle, page_bufs, 0, len, NULL,
do_journal_get_write_access);
--
2.18.0.rc0
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