From 4e8b44b6c2350e02ca8e410d40022122b4038bd5 Mon Sep 17 00:00:00 2001 From: "Emilio G. Cota" Date: Tue, 10 Apr 2018 10:47:12 -0400 Subject: target/xtensa: avoid integer overflow in next_page PC check If the PC is in the last page of the address space, next_page_start overflows to 0. Fix it. Reviewed-by: Richard Henderson Acked-by: Max Filippov Cc: Max Filippov Signed-off-by: Emilio G. Cota Signed-off-by: Richard Henderson --- target/xtensa/translate.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/target/xtensa/translate.c b/target/xtensa/translate.c index 4f6d03059f..aad496347d 100644 --- a/target/xtensa/translate.c +++ b/target/xtensa/translate.c @@ -1061,8 +1061,7 @@ void gen_intermediate_code(CPUState *cs, TranslationBlock *tb) int insn_count = 0; int max_insns = tb_cflags(tb) & CF_COUNT_MASK; uint32_t pc_start = tb->pc; - uint32_t next_page_start = - (pc_start & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE; + uint32_t page_start = pc_start & TARGET_PAGE_MASK; if (max_insns == 0) { max_insns = CF_COUNT_MASK; @@ -1162,9 +1161,9 @@ void gen_intermediate_code(CPUState *cs, TranslationBlock *tb) } } while (dc.is_jmp == DISAS_NEXT && insn_count < max_insns && - dc.pc < next_page_start && - dc.pc + xtensa_insn_len(env, &dc) <= next_page_start && - !tcg_op_buf_full()); + dc.pc - page_start < TARGET_PAGE_SIZE && + dc.pc - page_start + xtensa_insn_len(env, &dc) <= TARGET_PAGE_SIZE + && !tcg_op_buf_full()); done: reset_sar_tracker(&dc); if (dc.icount) { -- cgit v1.2.1