decompress_bunzip2: off by one in get_next_block()

decompress_bunzip2: off by one in get_next_block()

"origPtr" is used as an offset into the bd->dbuf[] array.  That array is
allocated in start_bunzip() and has "bd->dbufSize" number of elements so
the test here should be >= instead of >.

Later we check "origPtr" again before using it as an offset so I don't
know if this bug can be triggered in real life.

Fixes: bc22c17e12c1 ('bzip2/lzma: library support for gzip, bzip2 and lzma decompression')
Signed-off-by: Dan Carpenter <[email protected]>
Cc: Alain Knaff <[email protected]>
Cc: Yinghai Lu <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>