This is a note to let you know that I've just added the patch titled
nilfs2: fix data corruption in dsync block recovery for small block sizes
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nilfs2-fix-data-corruption-in-dsync-block-recovery-for-small-block-sizes.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 67b8bcbaed4777871bb0dcc888fb02a614a98ab1 Mon Sep 17 00:00:00 2001
From: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Date: Wed, 24 Jan 2024 21:19:36 +0900
Subject: nilfs2: fix data corruption in dsync block recovery for small block sizes
From: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
commit 67b8bcbaed4777871bb0dcc888fb02a614a98ab1 upstream.
The helper function nilfs_recovery_copy_block() of
nilfs_recovery_dsync_blocks(), which recovers data from logs created by
data sync writes during a mount after an unclean shutdown, incorrectly
calculates the on-page offset when copying repair data to the file's page
cache. In environments where the block size is smaller than the page
size, this flaw can cause data corruption and leak uninitialized memory
bytes during the recovery process.
Fix these issues by correcting this byte offset calculation on the page.
Link: https://lkml.kernel.org/r/20240124121936.10575-1-konishi.ryusuke@xxxxxxxxx
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Tested-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/nilfs2/recovery.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
--- a/fs/nilfs2/recovery.c
+++ b/fs/nilfs2/recovery.c
@@ -472,9 +472,10 @@ static int nilfs_prepare_segment_for_rec
static int nilfs_recovery_copy_block(struct the_nilfs *nilfs,
struct nilfs_recovery_block *rb,
- struct page *page)
+ loff_t pos, struct page *page)
{
struct buffer_head *bh_org;
+ size_t from = pos & ~PAGE_MASK;
void *kaddr;
bh_org = __bread(nilfs->ns_bdev, rb->blocknr, nilfs->ns_blocksize);
@@ -482,7 +483,7 @@ static int nilfs_recovery_copy_block(str
return -EIO;
kaddr = kmap_atomic(page);
- memcpy(kaddr + bh_offset(bh_org), bh_org->b_data, bh_org->b_size);
+ memcpy(kaddr + from, bh_org->b_data, bh_org->b_size);
kunmap_atomic(kaddr);
brelse(bh_org);
return 0;
@@ -521,7 +522,7 @@ static int nilfs_recover_dsync_blocks(st
goto failed_inode;
}
- err = nilfs_recovery_copy_block(nilfs, rb, page);
+ err = nilfs_recovery_copy_block(nilfs, rb, pos, page);
if (unlikely(err))
goto failed_page;
Patches currently in stable-queue which might be from konishi.ryusuke@xxxxxxxxx are
queue-4.19/nilfs2-fix-data-corruption-in-dsync-block-recovery-for-small-block-sizes.patch
queue-4.19/nilfs2-fix-hang-in-nilfs_lookup_dirty_data_buffers.patch
