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Diffstat (limited to 'fs/quota')
-rw-r--r--fs/quota/quota_tree.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/fs/quota/quota_tree.c b/fs/quota/quota_tree.c
index 5f2405994280..7e65d67de9f3 100644
--- a/fs/quota/quota_tree.c
+++ b/fs/quota/quota_tree.c
@@ -71,6 +71,35 @@ 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, const char *val_name,
+ uint val, uint min_val, uint max_val)
+{
+ if (val < min_val || val > max_val) {
+ quota_error(sb, "Getting %s %u out of range %u-%u",
+ val_name, val, min_val, max_val);
+ return -EUCLEAN;
+ }
+
+ return 0;
+}
+
+static int check_dquot_block_header(struct qtree_mem_dqinfo *info,
+ struct qt_disk_dqdbheader *dh)
+{
+ int err = 0;
+
+ err = do_check_range(info->dqi_sb, "dqdh_next_free",
+ le32_to_cpu(dh->dqdh_next_free), 0,
+ info->dqi_blocks - 1);
+ if (err)
+ return err;
+ err = do_check_range(info->dqi_sb, "dqdh_prev_free",
+ le32_to_cpu(dh->dqdh_prev_free), 0,
+ info->dqi_blocks - 1);
+
+ return err;
+}
+
/* Remove empty block from list and return it */
static int get_free_dqblk(struct qtree_mem_dqinfo *info)
{
@@ -85,6 +114,9 @@ static int get_free_dqblk(struct qtree_mem_dqinfo *info)
ret = read_blk(info, blk, buf);
if (ret < 0)
goto out_buf;
+ ret = check_dquot_block_header(info, dh);
+ if (ret)
+ goto out_buf;
info->dqi_free_blk = le32_to_cpu(dh->dqdh_next_free);
}
else {
@@ -232,6 +264,9 @@ static uint find_free_dqentry(struct qtree_mem_dqinfo *info,
*err = read_blk(info, blk, buf);
if (*err < 0)
goto out_buf;
+ *err = check_dquot_block_header(info, dh);
+ if (*err)
+ goto out_buf;
} else {
blk = get_free_dqblk(info);
if ((int)blk < 0) {
@@ -424,6 +459,9 @@ static int free_dqentry(struct qtree_mem_dqinfo *info, struct dquot *dquot,
goto out_buf;
}
dh = (struct qt_disk_dqdbheader *)buf;
+ ret = check_dquot_block_header(info, dh);
+ if (ret)
+ goto out_buf;
le16_add_cpu(&dh->dqdh_entries, -1);
if (!le16_to_cpu(dh->dqdh_entries)) { /* Block got free? */
ret = remove_free_dqentry(info, buf, blk);