It would be better to do more sanity checking (eg. dqdh_entries,
block no.) for the content read from quota file, which can prevent
corrupting the quota file.
Signed-off-by: Zhihao Cheng <chengzhihao1@xxxxxxxxxx>
---
fs/quota/quota_tree.c | 43 +++++++++++++++++++++++++++++++++----------
1 file changed, 33 insertions(+), 10 deletions(-)
diff --git a/fs/quota/quota_tree.c b/fs/quota/quota_tree.c
index 47711e739ddb..54fe4ad71de5 100644
--- a/fs/quota/quota_tree.c
+++ b/fs/quota/quota_tree.c
@@ -71,12 +71,12 @@ static ssize_t write_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf)
return ret;
}
-static inline int do_check_range(struct super_block *sb, uint val,
- uint min_val, uint max_val)
+static inline int do_check_range(struct super_block *sb, const char *val_name,
+ uint val, uint min_val, uint max_val)
{
if (val < min_val || val >= max_val) {
- quota_error(sb, "Getting block %u out of range %u-%u",
- val, min_val, max_val);
+ quota_error(sb, "Getting %s %u out of range %u-%u",
+ val_name, val, min_val, max_val);
return -EUCLEAN;
}
@@ -90,11 +90,13 @@ static int check_dquot_block_header(struct qtree_mem_dqinfo *info,
uint nextblk, prevblk;
nextblk = le32_to_cpu(dh->dqdh_next_free);
- err = do_check_range(info->dqi_sb, nextblk, 0, info->dqi_blocks);
+ err = do_check_range(info->dqi_sb, "dqdh_next_free", nextblk, 0,
+ info->dqi_blocks);
if (err)
return err;
prevblk = le32_to_cpu(dh->dqdh_prev_free);
- err = do_check_range(info->dqi_sb, prevblk, 0, info->dqi_blocks);
+ err = do_check_range(info->dqi_sb, "dqdh_prev_free", prevblk, 0,
+ info->dqi_blocks);
if (err)
return err;
@@ -268,6 +270,11 @@ static uint find_free_dqentry(struct qtree_mem_dqinfo *info,
*err = check_dquot_block_header(info, dh);
if (*err)
goto out_buf;
+ *err = do_check_range(info->dqi_sb, "dqdh_entries",
+ le16_to_cpu(dh->dqdh_entries), 0,
+ qtree_dqstr_in_blk(info));
+ if (*err)
+ goto out_buf;
} else {
blk = get_free_dqblk(info);
if ((int)blk < 0) {
@@ -349,6 +356,10 @@ static int do_insert_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot,
}
ref = (__le32 *)buf;
newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]);
+ ret = do_check_range(dquot->dq_sb, "block", newblk, 0,
+ info->dqi_blocks);
+ if (ret)
+ goto out_buf;
if (!newblk)
newson = 1;
if (depth == info->dqi_qtree_depth - 1) {
@@ -461,6 +472,11 @@ static int free_dqentry(struct qtree_mem_dqinfo *info, struct dquot *dquot,
}
dh = (struct qt_disk_dqdbheader *)buf;
ret = check_dquot_block_header(info, dh);
+ if (ret)
+ goto out_buf;
+ ret = do_check_range(info->dqi_sb, "dqdh_entries",
+ le16_to_cpu(dh->dqdh_entries), 1,
+ qtree_dqstr_in_blk(info) + 1);
if (ret)
goto out_buf;
le16_add_cpu(&dh->dqdh_entries, -1);
@@ -519,7 +535,7 @@ 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)]);
- ret = do_check_range(dquot->dq_sb, newblk, QT_TREEOFF,
+ ret = do_check_range(dquot->dq_sb, "block", newblk, QT_TREEOFF,
info->dqi_blocks);
if (ret)
goto out_buf;
@@ -623,7 +639,8 @@ 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;
- ret = do_check_range(dquot->dq_sb, blk, QT_TREEOFF, info->dqi_blocks);
+ ret = do_check_range(dquot->dq_sb, "block", blk, QT_TREEOFF,
+ info->dqi_blocks);
if (ret)
goto out_buf;
@@ -739,7 +756,13 @@ static int find_next_id(struct qtree_mem_dqinfo *info, qid_t *id,
goto out_buf;
}
for (i = __get_index(info, *id, depth); i < epb; i++) {
- if (ref[i] == cpu_to_le32(0)) {
+ uint blk_no = le32_to_cpu(ref[i]);
+
+ ret = do_check_range(info->dqi_sb, "block", blk_no, 0,
+ info->dqi_blocks);
+ if (ret)
+ goto out_buf;
+ if (blk_no == 0) {
*id += level_inc;
continue;
}
@@ -747,7 +770,7 @@ static int find_next_id(struct qtree_mem_dqinfo *info, qid_t *id,
ret = 0;
goto out_buf;
}
- ret = find_next_id(info, id, le32_to_cpu(ref[i]), depth + 1);
+ ret = find_next_id(info, id, blk_no, depth + 1);
if (ret != -ENOENT)
break;
}
--
2.31.1
