tbio: fix cmd_len handling
sizeof(rq->cmd) does not return the size of cmd buffer in rq,
it will return the size of the pointer, i.e. 4 - on 32-bit systems,
and 8 - on 64-bit systems. This happens, because cmd is a pointer to
__cmd[BLK_MAX_CDB] in struct request in the kernel (see linux/blkdev.h):
unsigned char __cmd[BLK_MAX_CDB];
unsigned char *cmd;
unsigned short cmd_len;
and is not a static buffer by itself.
Therefore on 32-bit systems 'sizeof(rq->cmd) - inter->cmd_len)' will be
'4 - 6', and this is not what we want.
Corrected this, so now we rely on inter->cmd containing a null-terminated string,
and inter->cmd_len containing the exact number of bytes to store this string.
Signed-off-by: Stanislav Kholmanskikh <stanislav.kholmanskikh@oracle.com>
Acked-by: Cyril Hrubis <chrubis@suse.cz>
3 files changed