On Thu, Dec 8, 2022 at 3:40 PM Amadeusz Sławiński <amadeuszx.slawinski@xxxxxxxxxxxxxxx> wrote: > > In our tests we get UBSAN warning coming from ACPI parser. This is > caused by trying to resolve operands when there is none. > > [ 0.000000] Linux version 5.15.0-rc3chromeavsrel1.0.184+ (root@...) (gcc (Ubuntu 10.3.0-1ubuntu1~20.04) 10.3.0, GNU ld (GNU Binutils for Ubuntu) 2.34) #1 SMP PREEMPT Sat Oct 16 00:08:27 UTC 2021 > ... > [ 14.719508] ================================================================================ > [ 14.719551] UBSAN: array-index-out-of-bounds in /.../linux/drivers/acpi/acpica/dswexec.c:401:12 > [ 14.719594] index -1 is out of range for type 'acpi_operand_object *[9]' > [ 14.719621] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc3chromeavsrel1.0.184+ #1 > [ 14.719657] Hardware name: Intel Corp. Geminilake/GLK RVP2 LP4SD (07), BIOS GELKRVPA.X64.0214.B50.2009111159 09/11/2020 > [ 14.719694] Call Trace: > [ 14.719712] dump_stack_lvl+0x38/0x49 > [ 14.719749] dump_stack+0x10/0x12 > [ 14.719775] ubsan_epilogue+0x9/0x45 > [ 14.719801] __ubsan_handle_out_of_bounds.cold+0x44/0x49 > [ 14.719835] acpi_ds_exec_end_op+0x1d7/0x6b5 > [ 14.719870] acpi_ps_parse_loop+0x942/0xb34 > ... > > Problem happens because WalkState->NumOperands is 0 and it is used when > trying to access into operands table. Actual code is: > WalkState->Operands [WalkState->NumOperands -1] > which causes out of bound access. Improve the check before above access > to check if ACPI opcode should have any arguments (operands) at all. > > Link: https://github.com/acpica/acpica/pull/745 > Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@xxxxxxxxxxxxxxx> > Reviewed-by: Cezary Rojewski <cezary.rojewski@xxxxxxxxx> > --- > > Changes: > v2: Fix comment to tell that opcode has no arguments > > --- > drivers/acpi/acpica/dswexec.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/acpi/acpica/dswexec.c b/drivers/acpi/acpica/dswexec.c > index e8ad41387f84..b082eb942a0f 100644 > --- a/drivers/acpi/acpica/dswexec.c > +++ b/drivers/acpi/acpica/dswexec.c > @@ -389,9 +389,11 @@ acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state) > > /* > * All opcodes require operand resolution, with the only exceptions > - * being the object_type and size_of operators. > + * being the object_type and size_of operators as well as opcodes that > + * take no arguments. > */ > - if (!(walk_state->op_info->flags & AML_NO_OPERAND_RESOLVE)) { > + if (!(walk_state->op_info->flags & AML_NO_OPERAND_RESOLVE) && > + (walk_state->op_info->flags & AML_HAS_ARGS)) { > > /* Resolve all operands */ > > -- Applied, thanks!
