[v1] target/s390x: Miscellaneous TCG fixes

[PATCH 07/12] target/s390x: Fix relative long instructions with large offsets

Posted by Ilya Leoshkevich 2 years, 7 months ago

The expression "imm * 2" in gen_ri2() can wrap around if imm is large
enough.

Fix by casting imm to int64_t, like it's done in disas_jdest().

Fixes: e8ecdfeb30f0 ("Fix EXECUTE of relative branches")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 target/s390x/tcg/translate.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/s390x/tcg/translate.c b/target/s390x/tcg/translate.c
index a6079ab7b4f..6661b27efa4 100644
--- a/target/s390x/tcg/translate.c
+++ b/target/s390x/tcg/translate.c
@@ -5794,7 +5794,7 @@ static TCGv gen_ri2(DisasContext *s)
 
     disas_jdest(s, i2, is_imm, imm, ri2);
     if (is_imm) {
-        ri2 = tcg_constant_i64(s->base.pc_next + imm * 2);
+        ri2 = tcg_constant_i64(s->base.pc_next + (int64_t)imm * 2);
     }
 
     return ri2;
-- 
2.41.0

Re: [PATCH 07/12] target/s390x: Fix relative long instructions with large offsets

Posted by David Hildenbrand 2 years, 7 months ago

On 03.07.23 17:50, Ilya Leoshkevich wrote:
> The expression "imm * 2" in gen_ri2() can wrap around if imm is large
> enough.
> 
> Fix by casting imm to int64_t, like it's done in disas_jdest().
> 
> Fixes: e8ecdfeb30f0 ("Fix EXECUTE of relative branches")
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>   target/s390x/tcg/translate.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/target/s390x/tcg/translate.c b/target/s390x/tcg/translate.c
> index a6079ab7b4f..6661b27efa4 100644
> --- a/target/s390x/tcg/translate.c
> +++ b/target/s390x/tcg/translate.c
> @@ -5794,7 +5794,7 @@ static TCGv gen_ri2(DisasContext *s)
>   
>       disas_jdest(s, i2, is_imm, imm, ri2);
>       if (is_imm) {
> -        ri2 = tcg_constant_i64(s->base.pc_next + imm * 2);
> +        ri2 = tcg_constant_i64(s->base.pc_next + (int64_t)imm * 2);
>       }
>   
>       return ri2;

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb