Coverity has long complained about the checksum being uninitialized if
an END record is processed before its BEGIN record. This should not
happen, but there was no code to check for it. I had left this unfixed
since it was a low priority issue, but then
9f4ede63d2 added another instance of this.
I am making an effort to "hold the line" to keep new coverity defect
reports from going unaddressed, so I find myself forced to fix this much
earlier than I had originally planned to address it.
The solution is to maintain a counter and a flag. Then use VERIFY
statements to verify the following runtime constraints:
* Every record either has a corresponding BEGIN record, is a BEGIN
record or is the end of stream END record for replication streams.
* BEGIN records cannot be nested. i.e. There must be an END record
before another BEGIN record may be seen.
Failure to meet these constraints will cause the program to exit.
This is sufficient to ensure that the checksum is never accessed when
uninitialized.
Reported-by: Coverity (CID 1524578)
Reported-by: Coverity (CID 1524633)
Reported-by: Coverity (CID 1527295)
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Damian Szuberski <szuberskidamian@gmail.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#14176
As new compression algorithms are added to ZFS, it could be useful for
people to recompress data with new algorithms. There is currently no
mechanism to do this aside from copying the data manually into a new
filesystem with the new algorithm enabled. This tool allows the
transformation to happen through zfs send, allowing it to be done
efficiently to remote systems and in an incremental fashion.
A new zstream command is added that decompresses WRITE records and
then recompresses them with a provided algorithm, and then re-emits
the modified send stream. It may also be possible to re-compress
embedded block pointers, but that was not attempted for the initial
version.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes#14106
Richard Yao
Paul Dagnelie