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. CVSS 3.1 Base Score 7.7 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H).

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.

https://git.kernel.org/stable/c/ccd3f449052449a917a3e577d8ba0368f43b8f29