diff options
| author | Qu Wenruo <wqu@suse.com> | 2018-07-03 17:10:07 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-15 09:43:00 +0200 |
| commit | 93d960de56cef4582088dfc0ba9494143351772f (patch) | |
| tree | 830b79b15ee16fe2c7f2b3470df1e0eb4d5f89ab | |
| parent | e22b36a336fa637efb8f2d52fe1a8ebbd2cb1f57 (diff) | |
btrfs: relocation: Only remove reloc rb_trees if reloc control has been initialized
[ Upstream commit 389305b2aa68723c754f88d9dbd268a400e10664 ]
Invalid reloc tree can cause kernel NULL pointer dereference when btrfs
does some cleanup of the reloc roots.
It turns out that fs_info::reloc_ctl can be NULL in
btrfs_recover_relocation() as we allocate relocation control after all
reloc roots have been verified.
So when we hit: note, we haven't called set_reloc_control() thus
fs_info::reloc_ctl is still NULL.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=199833
Reported-by: Xu Wen <wen.xu@gatech.edu>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Tested-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/btrfs/relocation.c | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 04c61bcf62e5..9140aede5869 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -1325,18 +1325,19 @@ static void __del_reloc_root(struct btrfs_root *root) struct mapping_node *node = NULL; struct reloc_control *rc = root->fs_info->reloc_ctl; - spin_lock(&rc->reloc_root_tree.lock); - rb_node = tree_search(&rc->reloc_root_tree.rb_root, - root->node->start); - if (rb_node) { - node = rb_entry(rb_node, struct mapping_node, rb_node); - rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); + if (rc) { + spin_lock(&rc->reloc_root_tree.lock); + rb_node = tree_search(&rc->reloc_root_tree.rb_root, + root->node->start); + if (rb_node) { + node = rb_entry(rb_node, struct mapping_node, rb_node); + rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); + } + spin_unlock(&rc->reloc_root_tree.lock); + if (!node) + return; + BUG_ON((struct btrfs_root *)node->data != root); } - spin_unlock(&rc->reloc_root_tree.lock); - - if (!node) - return; - BUG_ON((struct btrfs_root *)node->data != root); spin_lock(&root->fs_info->trans_lock); list_del_init(&root->root_list); |