linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright (C) Qu Wenruo 2017.  All rights reserved.

 */

​

/*

 * The module is used to catch unexpected/corrupted tree block data.

 * Such behavior can be caused either by a fuzzed image or bugs.

 *

 * The objective is to do leaf/node validation checks when tree block is read

 * from disk, and check *every* possible member, so other code won't

 * need to checking them again.

 *

 * Due to the potential and unwanted damage, every checker needs to be

 * carefully reviewed otherwise so it does not prevent mount of valid images.

 */

​

#include "ctree.h"

#include "tree-checker.h"

#include "disk-io.h"

#include "compression.h"

#include "volumes.h"

​

/*

 * Error message should follow the following format:

 * corrupt <type>: <identifier>, <reason>[, <bad_value>]

 *

 * @type:   leaf or node

 * @identifier: the necessary info to locate the leaf/node.

 *      It's recommended to decode key.objecitd/offset if it's

 *      meaningful.

 * @reason: describe the error

 * @bad_value:  optional, it's recommended to output bad value and its

 *      expected value (range).

 *

 * Since comma is used to separate the components, only space is allowed

 * inside each component.

 */

​

/*

 * Append generic "corrupt leaf/node root=%llu block=%llu slot=%d: " to @fmt.

 * Allows callers to customize the output.

 */

__printf(4, 5)

__cold

static void generic_err(const struct btrfs_fs_info *fs_info,

            const struct extent_buffer *eb, int slot,

            const char *fmt, ...)

{

    struct va_format vaf;

    va_list args;

​

    va_start(args, fmt);

​

    vaf.fmt = fmt;

    vaf.va = &args;

​

    btrfs_crit(fs_info,

        "corrupt %s: root=%llu block=%llu slot=%d, %pV",

        btrfs_header_level(eb) == 0 ? "leaf" : "node",

        btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot, &vaf);

    va_end(args);

}

​

/*

 * Customized reporter for extent data item, since its key objectid and

 * offset has its own meaning.

 */

__printf(4, 5)

__cold

static void file_extent_err(const struct btrfs_fs_info *fs_info,

                const struct extent_buffer *eb, int slot,

                const char *fmt, ...)

{

    struct btrfs_key key;

    struct va_format vaf;

    va_list args;

​

    btrfs_item_key_to_cpu(eb, &key, slot);

    va_start(args, fmt);

​

    vaf.fmt = fmt;

    vaf.va = &args;

​

    btrfs_crit(fs_info,

    "corrupt %s: root=%llu block=%llu slot=%d ino=%llu file_offset=%llu, %pV",

        btrfs_header_level(eb) == 0 ? "leaf" : "node",

        btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,

        key.objectid, key.offset, &vaf);

    va_end(args);

}

​