Message ID | 20220922130401.1792256-4-chengzhihao1@huawei.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Check content after reading from quota file | expand |
On Thu 22-09-22 21:04:01, Zhihao Cheng wrote: > 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@huawei.com> > --- > 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; > } As I already wrote in my comments to v1, please create do_check_range() already with this prototype in patch 1 so that you don't have to update it (and all the call sites) in each of the patches. It makes review simpler. > @@ -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; The checking of dqdh_entries belongs into check_dquot_block_header(). That was the reason why it was created. So that all the checks are together in one function... > } 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); Again, the check of dqdh_entries should be in check_dquot_block_header(). > @@ -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; > } I'd leave checking for 0 first here - i.e.: if (ref[i] == cpu_to_le32(0)) { *id += level_inc; continue; } and only then do: blk_no = le32_to_cpu(ref[i]); ret = do_check_range(...); There's no point in checking known-good value. Honza
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; }
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@huawei.com> --- fs/quota/quota_tree.c | 43 +++++++++++++++++++++++++++++++++---------- 1 file changed, 33 insertions(+), 10 deletions(-)