scsi: target: Fix WRITE_SAME No Data Buffer crash

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: scsi: target: Fix WRITE_SAME No Data Buffer crash In newer version of the SBC specs, we have a NDOB bit that indicates there is no data buffer that gets written out. If this bit is set using commands like "sg_write_same --ndob" we will crash in target_core_iblock/file's execute_write_same handlers when we go to access the se_cmd->t_data_sg because its NULL. This patch adds a check for the NDOB bit in the common WRITE SAME code because we don't support it. And, it adds a check for zero SG elements in each handler in case the initiator tries to send a normal WRITE SAME with no data buffer.

References

• https://git.kernel.org/stable/c/54e57be2573cf0b8bf650375fd8752987b6c3d3b
• https://git.kernel.org/stable/c/d8e6a27e9238dd294d6f2f401655f300dca20899
• https://git.kernel.org/stable/c/4226622647e3e5ac06d3ebc1605b917446157510
• https://git.kernel.org/stable/c/ccd3f449052449a917a3e577d8ba0368f43b8f29