This is a note to let you know that I've just added the patch titled
quota: check block number when reading the block in quota file
to the 4.4-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:
quota-check-block-number-when-reading-the-block-in-quota-file.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 9bf3d20331295b1ecb81f4ed9ef358c51699a050 Mon Sep 17 00:00:00 2001
From: Zhang Yi <yi.zhang@xxxxxxxxxx>
Date: Fri, 8 Oct 2021 17:38:20 +0800
Subject: quota: check block number when reading the block in quota file
From: Zhang Yi <yi.zhang@xxxxxxxxxx>
commit 9bf3d20331295b1ecb81f4ed9ef358c51699a050 upstream.
The block number in the quota tree on disk should be smaller than the
v2_disk_dqinfo.dqi_blocks. If the quota file was corrupted, we may be
allocating an 'allocated' block and that would lead to a loop in a tree,
which will probably trigger oops later. This patch adds a check for the
block number in the quota tree to prevent such potential issue.
Link: https://lore.kernel.org/r/20211008093821.1001186-2-yi.zhang@xxxxxxxxxx
Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
Cc: stable@xxxxxxxxxx
Signed-off-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/quota/quota_tree.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
--- a/fs/quota/quota_tree.c
+++ b/fs/quota/quota_tree.c
@@ -481,6 +481,13 @@ static int remove_tree(struct qtree_mem_
goto out_buf;
}
newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]);
+ if (newblk < QT_TREEOFF || newblk >= info->dqi_blocks) {
+ quota_error(dquot->dq_sb, "Getting block too big (%u >= %u)",
+ newblk, info->dqi_blocks);
+ ret = -EUCLEAN;
+ goto out_buf;
+ }
+
if (depth == info->dqi_qtree_depth - 1) {
ret = free_dqentry(info, dquot, newblk);
newblk = 0;
@@ -580,6 +587,13 @@ static loff_t find_tree_dqentry(struct q
blk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]);
if (!blk) /* No reference? */
goto out_buf;
+ if (blk < QT_TREEOFF || blk >= info->dqi_blocks) {
+ quota_error(dquot->dq_sb, "Getting block too big (%u >= %u)",
+ blk, info->dqi_blocks);
+ ret = -EUCLEAN;
+ goto out_buf;
+ }
+
if (depth < info->dqi_qtree_depth - 1)
ret = find_tree_dqentry(info, dquot, blk, depth+1);
else
Patches currently in stable-queue which might be from yi.zhang@xxxxxxxxxx are
queue-4.4/quota-correct-error-number-in-free_dqentry.patch
queue-4.4/quota-check-block-number-when-reading-the-block-in-quota-file.patch
