mirror of
https://github.com/xemu-project/xemu.git
synced 2025-02-24 22:50:42 +00:00

if QEMU is started with used provided SLIC table blob, -acpitable sig=SLIC,oem_id='CRASH ',oem_table_id="ME",oem_rev=00002210,asl_compiler_id="",asl_compiler_rev=00000000,data=/dev/null it will assert with: hw/acpi/aml-build.c:61:build_append_padded_str: assertion failed: (len <= maxlen) and following backtrace: ... build_append_padded_str (array=0x555556afe320, str=0x555556afdb2e "CRASH ME", maxlen=0x6, pad=0x20) at hw/acpi/aml-build.c:61 acpi_table_begin (desc=0x7fffffffd1b0, array=0x555556afe320) at hw/acpi/aml-build.c:1727 build_fadt (tbl=0x555556afe320, linker=0x555557ca3830, f=0x7fffffffd318, oem_id=0x555556afdb2e "CRASH ME", oem_table_id=0x555556afdb34 "ME") at hw/acpi/aml-build.c:2064 ... which happens due to acpi_table_begin() expecting NULL terminated oem_id and oem_table_id strings, which is normally the case, but in case of user provided SLIC table, oem_id points to table's blob directly and as result oem_id became longer than expected. Fix issue by handling oem_id consistently and make acpi_get_slic_oem() return NULL terminated strings. PS: After [1] refactoring, oem_id semantics became inconsistent, where NULL terminated string was coming from machine and old way pointer into byte array coming from -acpitable option. That used to work since build_header() wasn't expecting NULL terminated string and blindly copied the 1st 6 bytes only. However commit [2] broke that by replacing build_header() with acpi_table_begin(), which was expecting NULL terminated string and was checking oem_id size. 1) 602b45820 ("acpi: Permit OEM ID and OEM table ID fields to be changed") 2) Fixes: 4b56e1e4eb08 ("acpi: build_fadt: use acpi_table_begin()/acpi_table_end() instead of build_header()") Resolves: https://gitlab.com/qemu-project/qemu/-/issues/786 Signed-off-by: Igor Mammedov <imammedo@redhat.com> Message-Id: <20211227193120.1084176-2-imammedo@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Tested-by: Denis Lisov <dennis.lissov@gmail.com> Tested-by: Alexander Tsoy <alexander@tsoy.me> Cc: qemu-stable@nongnu.org Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>