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author | Liu Bo <bo.li.liu@oracle.com> | 2016-08-24 00:37:45 (GMT) |
---|---|---|
committer | Chris Mason <clm@fb.com> | 2016-08-25 10:58:30 (GMT) |
commit | 053ab70f0604224c7893b43f9d9d5efa283580d6 (patch) | |
tree | 7f2ac232c96eafbfbc71a85337ad935d9e599473 | |
parent | 35bbb97fc898aeb874cb7c8b746f091caa359994 (diff) | |
download | linux-053ab70f0604224c7893b43f9d9d5efa283580d6.tar.xz |
Btrfs: check btree node's nritems
When btree node (level = 1) has nritems which equals to zero,
we can end up with panic due to insert_ptr()'s
BUG_ON(slot > nritems);
where slot is 1 and nritems is 0, as copy_for_split() calls
insert_ptr(.., path->slots[1] + 1, ...);
A invalid value results in the whole mess, this adds the check
for btree's node nritems so that we stop reading block when
when something is wrong.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
-rw-r--r-- | fs/btrfs/disk-io.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index edda471..474209f 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -613,6 +613,19 @@ static noinline int check_leaf(struct btrfs_root *root, return 0; } +static int check_node(struct btrfs_root *root, struct extent_buffer *node) +{ + unsigned long nr = btrfs_header_nritems(node); + + if (nr == 0 || nr > BTRFS_NODEPTRS_PER_BLOCK(root)) { + btrfs_crit(root->fs_info, + "corrupt node: block %llu root %llu nritems %lu", + node->start, root->objectid, nr); + return -EIO; + } + return 0; +} + static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio, u64 phy_offset, struct page *page, u64 start, u64 end, int mirror) @@ -683,6 +696,9 @@ static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio, ret = -EIO; } + if (found_level > 0 && check_node(root, eb)) + ret = -EIO; + if (!ret) set_extent_buffer_uptodate(eb); err: |