Btrfs: fix memory leaks on walking backrefs failure

When walking backrefs, we may iterate every inode's extent
and add/merge them into ulist, and the caller will free memory
from ulist.

However, if we fail to allocate inode's extents element
memory or ulist_add() fail to allocate memory, we won't
add allocated memory into ulist, and the caller won't
free some allocated memory thus memory leaks happen.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
This commit is contained in:
Wang Shilong 2014-01-28 19:13:38 +08:00 committed by Chris Mason
parent bf54f412f0
commit f05c474688
1 changed files with 18 additions and 7 deletions

View File

@ -66,6 +66,16 @@ static int check_extent_in_eb(struct btrfs_key *key, struct extent_buffer *eb,
return 0; return 0;
} }
static void free_inode_elem_list(struct extent_inode_elem *eie)
{
struct extent_inode_elem *eie_next;
for (; eie; eie = eie_next) {
eie_next = eie->next;
kfree(eie);
}
}
static int find_extent_in_eb(struct extent_buffer *eb, u64 wanted_disk_byte, static int find_extent_in_eb(struct extent_buffer *eb, u64 wanted_disk_byte,
u64 extent_item_pos, u64 extent_item_pos,
struct extent_inode_elem **eie) struct extent_inode_elem **eie)
@ -275,6 +285,7 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
old = old->next; old = old->next;
old->next = eie; old->next = eie;
} }
eie = NULL;
} }
next: next:
ret = btrfs_next_old_item(root, path, time_seq); ret = btrfs_next_old_item(root, path, time_seq);
@ -282,6 +293,8 @@ next:
if (ret > 0) if (ret > 0)
ret = 0; ret = 0;
else if (ret < 0)
free_inode_elem_list(eie);
return ret; return ret;
} }
@ -845,6 +858,7 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans,
struct list_head prefs_delayed; struct list_head prefs_delayed;
struct list_head prefs; struct list_head prefs;
struct __prelim_ref *ref; struct __prelim_ref *ref;
struct extent_inode_elem *eie = NULL;
INIT_LIST_HEAD(&prefs); INIT_LIST_HEAD(&prefs);
INIT_LIST_HEAD(&prefs_delayed); INIT_LIST_HEAD(&prefs_delayed);
@ -958,7 +972,6 @@ again:
goto out; goto out;
} }
if (ref->count && ref->parent) { if (ref->count && ref->parent) {
struct extent_inode_elem *eie = NULL;
if (extent_item_pos && !ref->inode_list) { if (extent_item_pos && !ref->inode_list) {
u32 bsz; u32 bsz;
struct extent_buffer *eb; struct extent_buffer *eb;
@ -993,6 +1006,7 @@ again:
eie = eie->next; eie = eie->next;
eie->next = ref->inode_list; eie->next = ref->inode_list;
} }
eie = NULL;
} }
list_del(&ref->list); list_del(&ref->list);
kmem_cache_free(btrfs_prelim_ref_cache, ref); kmem_cache_free(btrfs_prelim_ref_cache, ref);
@ -1011,7 +1025,8 @@ out:
list_del(&ref->list); list_del(&ref->list);
kmem_cache_free(btrfs_prelim_ref_cache, ref); kmem_cache_free(btrfs_prelim_ref_cache, ref);
} }
if (ret < 0)
free_inode_elem_list(eie);
return ret; return ret;
} }
@ -1019,7 +1034,6 @@ static void free_leaf_list(struct ulist *blocks)
{ {
struct ulist_node *node = NULL; struct ulist_node *node = NULL;
struct extent_inode_elem *eie; struct extent_inode_elem *eie;
struct extent_inode_elem *eie_next;
struct ulist_iterator uiter; struct ulist_iterator uiter;
ULIST_ITER_INIT(&uiter); ULIST_ITER_INIT(&uiter);
@ -1027,10 +1041,7 @@ static void free_leaf_list(struct ulist *blocks)
if (!node->aux) if (!node->aux)
continue; continue;
eie = (struct extent_inode_elem *)(uintptr_t)node->aux; eie = (struct extent_inode_elem *)(uintptr_t)node->aux;
for (; eie; eie = eie_next) { free_inode_elem_list(eie);
eie_next = eie->next;
kfree(eie);
}
node->aux = 0; node->aux = 0;
} }