• Filipe Manana's avatar
    Btrfs: fix copy_items() return value when logging an inode · 8434ec46
    Filipe Manana authored
    When logging an inode, at tree-log.c:copy_items(), if we call
    btrfs_next_leaf() at the loop which checks for the need to log holes, we
    need to make sure copy_items() returns the value 1 to its caller and
    not 0 (on success). This is because the path the caller passed was
    released and is now different from what is was before, and the caller
    expects a return value of 0 to mean both success and that the path
    has not changed, while a return value of 1 means both success and
    signals the caller that it can not reuse the path, it has to perform
    another tree search.
    
    Even though this is a case that should not be triggered on normal
    circumstances or very rare at least, its consequences can be very
    unpredictable (especially when replaying a log tree).
    
    Fixes: 16e7549f ("Btrfs: incompatible format change to remove hole extents")
    Signed-off-by: default avatarFilipe Manana <fdmanana@suse.com>
    Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
    8434ec46
tree-log.c 160 KB