btrfs: fix qgroup record leaks when using simple quotas

When using simple quotas we are not supposed to allocate qgroup records
when adding delayed references. However we allocate them if either mode
of quotas is enabled (the new simple one or the old one), but then we
never free them because running the accounting, which frees the records,
is only run when using the old quotas (at btrfs_qgroup_account_extents()),
resulting in a memory leak of the records allocated when adding delayed
references.

Fix this by allocating the records only if the old quotas mode is enabled.
Also fix btrfs_qgroup_trace_extent_nolock() to return 1 if the old quotas
mode is not enabled - meaning the caller has to free the record.

Fixes: 182940f4f4db ("btrfs: qgroup: add new quota mode for simple quotas")
Reported-by: syzbot+d3ddc6dcc6386dea398b@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/00000000000004769106097f9a34@google.com/
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index 9223934d95f4724cbbc4e726306049d444112ee1..891ea2fa263c935707be62167f59c2c1474e9a8d 100644 (file)
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -1041,7 +1041,7 @@ int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans,
                return -ENOMEM;
        }
 
-       if (btrfs_qgroup_enabled(fs_info) && !generic_ref->skip_qgroup) {
+       if (btrfs_qgroup_full_accounting(fs_info) && !generic_ref->skip_qgroup) {
                record = kzalloc(sizeof(*record), GFP_NOFS);
                if (!record) {
                        kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
@@ -1144,7 +1144,7 @@ int btrfs_add_delayed_data_ref(struct btrfs_trans_handle *trans,
                return -ENOMEM;
        }
 
-       if (btrfs_qgroup_enabled(fs_info) && !generic_ref->skip_qgroup) {
+       if (btrfs_qgroup_full_accounting(fs_info) && !generic_ref->skip_qgroup) {
                record = kzalloc(sizeof(*record), GFP_NOFS);
                if (!record) {
                        kmem_cache_free(btrfs_delayed_data_ref_cachep, ref);

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index e48eba7e93793fd510b3bbb8e7658a1ac3f557ef..ce446d9d7f23da3f44cb9c7100c8e0d7b3866684 100644 (file)
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -1888,7 +1888,7 @@ int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info,
        u64 bytenr = record->bytenr;
 
        if (!btrfs_qgroup_full_accounting(fs_info))
-               return 0;
+               return 1;
 
        lockdep_assert_held(&delayed_refs->lock);
        trace_btrfs_qgroup_trace_extent(fs_info, record);