6.1-stable review patch. If anyone has any objections, please let me know.
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From: David Sterba dsterba@suse.com
[ Upstream commit ed4e6b5d644c4dd2bc2872ffec036b7da0ec2e27 ]
Syzbot hits a problem with enabled ref-verify, ignorebadroots and a fuzzed/damaged extent tree. There's no fallback option like in other places that can deal with it so disable the whole ref-verify as it is just a debugging feature.
Reported-by: syzbot+9c3e0cdfbfe351b0bc0e@syzkaller.appspotmail.com Link: https://lore.kernel.org/all/0000000000001b6052062139be1c@google.com/ Reviewed-by: Qu Wenruo wqu@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/btrfs/ref-verify.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/ref-verify.c b/fs/btrfs/ref-verify.c index 56ceb23bd7409..195fce42b982d 100644 --- a/fs/btrfs/ref-verify.c +++ b/fs/btrfs/ref-verify.c @@ -987,11 +987,18 @@ int btrfs_build_ref_tree(struct btrfs_fs_info *fs_info) if (!btrfs_test_opt(fs_info, REF_VERIFY)) return 0;
+ extent_root = btrfs_extent_root(fs_info, 0); + /* If the extent tree is damaged we cannot ignore it (IGNOREBADROOTS). */ + if (IS_ERR(extent_root)) { + btrfs_warn(fs_info, "ref-verify: extent tree not available, disabling"); + btrfs_clear_opt(fs_info->mount_opt, REF_VERIFY); + return 0; + } + path = btrfs_alloc_path(); if (!path) return -ENOMEM;
- extent_root = btrfs_extent_root(fs_info, 0); eb = btrfs_read_lock_root_node(extent_root); level = btrfs_header_level(eb); path->nodes[level] = eb;