Commit bb166d72 authored Aug 25, 2017 by Naohiro Aota Committed by David Sterba Sep 26, 2017

btrfs: fix NULL pointer dereference from free_reloc_roots()



__del_reloc_root should be called before freeing up reloc_root->node.
If not, calling __del_reloc_root() dereference reloc_root->node, causing
the system BUG.

Fixes: 6bdf131f ("Btrfs: don't leak reloc root nodes on error")
Cc: <stable@vger.kernel.org> # 4.9
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

parent 67c003f9

fs/btrfs/relocation.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -2400,11 +2400,11 @@ void free_reloc_roots(struct list_head *list)
		while (!list_empty(list)) {
		reloc_root = list_entry(list->next, struct btrfs_root,
		root_list);
		__del_reloc_root(reloc_root);
		free_extent_buffer(reloc_root->node);
		free_extent_buffer(reloc_root->commit_root);
		reloc_root->node = NULL;
		reloc_root->commit_root = NULL;
		__del_reloc_root(reloc_root);
		}
		}

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