The block number in the quota tree on disk should smaller than the
v2_disk_dqinfo.dqi_blocks. If the quota file was corrupted, we may
allocating an 'allocated' block and lead to the tree infinite loop,
which may probably trigger oops later. This patch add a check for
getting block number in the quota tree to prevent such potential issue.
Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
Cc: stable@xxxxxxxxxx
---
fs/quota/quota_tree.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/fs/quota/quota_tree.c b/fs/quota/quota_tree.c
index d3e995e1046f..583b7f7715f9 100644
--- a/fs/quota/quota_tree.c
+++ b/fs/quota/quota_tree.c
@@ -479,6 +479,13 @@ static int remove_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot,
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;
@@ -578,6 +585,13 @@ static loff_t find_tree_dqentry(struct qtree_mem_dqinfo *info,
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
--
2.31.1
