btrfs: handle chunk tree lookup error in btrfs_relocate_sys_chunks()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: btrfs: handle chunk tree lookup error in btrfs_relocate_sys_chunks() The unhandled case in btrfs_relocate_sys_chunks() loop is a corruption, as it could be caused only by two impossible conditions: - at first the search key is set up to look for a chunk tree item, with offset -1, this is an inexact search and the key->offset will contain the correct offset upon a successful search, a valid chunk tree item cannot have an offset -1 - after first successful search, the found_key corresponds to a chunk item, the offset is decremented by 1 before the next loop, it's impossible to find a chunk item there due to alignment and size constraints

References

• https://git.kernel.org/stable/c/bebd9e0ff90034875c5dfe4bd514fd7055fc7a89
• https://git.kernel.org/stable/c/576164bd01bd795f8b09fb194b493103506b33c9
• https://git.kernel.org/stable/c/87299cdaae757f3f41212146cfb5b3af416b8385
• https://git.kernel.org/stable/c/d1ffa4ae2d591fdd40471074e79954ec45f147f7
• https://git.kernel.org/stable/c/36c2a2863bc3896243eb724dc3fd4cf9aea633f2
• https://git.kernel.org/stable/c/0d23b34c68c46cd225b55868bc8a269e3134816d
• https://git.kernel.org/stable/c/1f9212cdbd005bc55f2b7422e7b560d9c02bd1da
• https://git.kernel.org/stable/c/7411055db5ce64f836aaffd422396af0075fdc99