[Qemu-devel] [PULL 05/28] target/unicore32: avoid integer overflow in next_page PC check

[Richard Henderson]

From: "Emilio G. Cota" <address@hidden>

If the PC is in the last page of the address space, next_page_start
overflows to 0. Fix it.

Reviewed-by: Richard Henderson <address@hidden>
Cc: Guan Xuetao <address@hidden>
Signed-off-by: Emilio G. Cota <address@hidden>
Signed-off-by: Richard Henderson <address@hidden>
---
 target/unicore32/translate.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/target/unicore32/translate.c b/target/unicore32/translate.c
index 5b51f2166d..abe2ea8592 100644
--- a/target/unicore32/translate.c
+++ b/target/unicore32/translate.c
@@ -1875,7 +1875,7 @@ void gen_intermediate_code(CPUState *cs, TranslationBlock 
*tb)
     CPUUniCore32State *env = cs->env_ptr;
     DisasContext dc1, *dc = &dc1;
     target_ulong pc_start;
-    uint32_t next_page_start;
+    uint32_t page_start;
     int num_insns;
     int max_insns;
 
@@ -1894,7 +1894,7 @@ void gen_intermediate_code(CPUState *cs, TranslationBlock 
*tb)
     cpu_F1s = tcg_temp_new_i32();
     cpu_F0d = tcg_temp_new_i64();
     cpu_F1d = tcg_temp_new_i64();
-    next_page_start = (pc_start & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE;
+    page_start = pc_start & TARGET_PAGE_MASK;
     num_insns = 0;
     max_insns = tb_cflags(tb) & CF_COUNT_MASK;
     if (max_insns == 0) {
@@ -1951,7 +1951,7 @@ void gen_intermediate_code(CPUState *cs, TranslationBlock 
*tb)
     } while (!dc->is_jmp && !tcg_op_buf_full() &&
              !cs->singlestep_enabled &&
              !singlestep &&
-             dc->pc < next_page_start &&
+             dc->pc - page_start < TARGET_PAGE_SIZE &&
              num_insns < max_insns);
 
     if (tb_cflags(tb) & CF_LAST_IO) {
-- 
2.17.0