Fix static analyzer error by ensuring 4 * total_ahs_len is
not larger than ISCSI_AHS_LEN.
When ./configure -enable-werror --enable-ubsan --enable-asan,
iscsi target reports heap-buffer-overflow error
when I feeding unexpeted pdu opcode.
Change-Id: Ib8053e1a19b5e49385642106eb79c458d35ab3c6
Signed-off-by: Hailiang Wang <hailiangx.e.wang@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/471489
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Liang Yan <liang.z.yan@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>