From nobody Thu Nov 14 06:58:01 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1706000032582663.7856735943666; Tue, 23 Jan 2024 00:53:52 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rSCSa-0001MF-4M; Tue, 23 Jan 2024 03:48:44 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rSCSX-0001LG-VZ; Tue, 23 Jan 2024 03:48:41 -0500 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rSCSV-0004tg-FN; Tue, 23 Jan 2024 03:48:41 -0500 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 80DF24666F; Tue, 23 Jan 2024 11:49:11 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id 42B06699ED; Tue, 23 Jan 2024 11:48:31 +0300 (MSK) Received: (nullmailer pid 3828105 invoked by uid 1000); Tue, 23 Jan 2024 08:48:31 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Richard Henderson , Paolo Bonzini , Michael Tokarev Subject: [Stable-7.2.9 10/20] target/i386: Fix 32-bit wrapping of pc/eip computation Date: Tue, 23 Jan 2024 11:48:20 +0300 Message-Id: <20240123084831.3828060-2-mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZM-MESSAGEID: 1706000032972100001 Content-Type: text/plain; charset="utf-8" From: Richard Henderson In 32-bit mode, pc =3D eip + cs_base is also 32-bit, and must wrap. Failure to do so results in incorrect memory exceptions to the guest. Before 732d548732ed, this was implicitly done via truncation to target_ulong but only in qemu-system-i386, not qemu-system-x86_64. To fix this, we must add conditional zero-extensions. Since we have to test for 32 vs 64-bit anyway, note that cs_base is always zero in 64-bit mode. Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2022 Signed-off-by: Richard Henderson Reviewed-by: Paolo Bonzini Message-Id: <20231212172510.103305-1-richard.henderson@linaro.org> (cherry picked from commit b5e0d5d22fbffc3d8f7d3e86d7a2d05a1a974e27) Signed-off-by: Michael Tokarev (Mjt: context fix in target/i386/tcg/tcg-cpu.c for v8.1.0-1190-gb77af26e97 "accel/tcg: Replace CPUState.env_ptr with cpu_env()") (Mjt: fixup in target/i386/tcg/tcg-cpu.c for v7.2.0-1854-g34a39c2443 "target/i386: Replace `tb_pc()` with `tb->pc`") diff --git a/target/i386/cpu.h b/target/i386/cpu.h index d4bc19577a..f67cee477a 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -2217,10 +2217,15 @@ static inline int cpu_mmu_index_kernel(CPUX86State = *env) static inline void cpu_get_tb_cpu_state(CPUX86State *env, target_ulong *pc, target_ulong *cs_base, uint32_t *f= lags) { - *cs_base =3D env->segs[R_CS].base; - *pc =3D *cs_base + env->eip; *flags =3D env->hflags | (env->eflags & (IOPL_MASK | TF_MASK | RF_MASK | VM_MASK | AC_MASK)= ); + if (env->hflags & HF_CS64_MASK) { + *cs_base =3D 0; + *pc =3D env->eip; + } else { + *cs_base =3D env->segs[R_CS].base; + *pc =3D (uint32_t)(*cs_base + env->eip); + } } =20 void do_cpu_init(X86CPU *cpu); diff --git a/target/i386/tcg/tcg-cpu.c b/target/i386/tcg/tcg-cpu.c index 79ac5908f7..563f42ee4e 100644 --- a/target/i386/tcg/tcg-cpu.c +++ b/target/i386/tcg/tcg-cpu.c @@ -52,7 +52,12 @@ static void x86_cpu_synchronize_from_tb(CPUState *cs, /* The instruction pointer is always up to date with TARGET_TB_PCREL. = */ if (!TARGET_TB_PCREL) { CPUX86State *env =3D cs->env_ptr; - env->eip =3D tb_pc(tb) - tb->cs_base; + + if (tb->flags & HF_CS64_MASK) { + env->eip =3D tb_pc(tb); + } else { + env->eip =3D (uint32_t)(tb_pc(tb) - tb->cs_base); + } } } =20 @@ -66,8 +71,10 @@ static void x86_restore_state_to_opc(CPUState *cs, =20 if (TARGET_TB_PCREL) { env->eip =3D (env->eip & TARGET_PAGE_MASK) | data[0]; + } else if (tb->flags & HF_CS64_MASK) { + env->eip =3D data[0]; } else { - env->eip =3D data[0] - tb->cs_base; + env->eip =3D (uint32_t)(data[0] - tb->cs_base); } if (cc_op !=3D CC_OP_DYNAMIC) { env->cc_op =3D cc_op; diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c index 7e0b2a709a..15b030d84b 100644 --- a/target/i386/tcg/translate.c +++ b/target/i386/tcg/translate.c @@ -547,8 +547,10 @@ static void gen_update_eip_cur(DisasContext *s) assert(s->pc_save !=3D -1); if (TARGET_TB_PCREL) { tcg_gen_addi_tl(cpu_eip, cpu_eip, s->base.pc_next - s->pc_save); + } else if (CODE64(s)) { + tcg_gen_movi_tl(cpu_eip, s->base.pc_next); } else { - tcg_gen_movi_tl(cpu_eip, s->base.pc_next - s->cs_base); + tcg_gen_movi_tl(cpu_eip, (uint32_t)(s->base.pc_next - s->cs_base)); } s->pc_save =3D s->base.pc_next; } @@ -558,8 +560,10 @@ static void gen_update_eip_next(DisasContext *s) assert(s->pc_save !=3D -1); if (TARGET_TB_PCREL) { tcg_gen_addi_tl(cpu_eip, cpu_eip, s->pc - s->pc_save); + } else if (CODE64(s)) { + tcg_gen_movi_tl(cpu_eip, s->base.pc_next); } else { - tcg_gen_movi_tl(cpu_eip, s->pc - s->cs_base); + tcg_gen_movi_tl(cpu_eip, (uint32_t)(s->base.pc_next - s->cs_base)); } s->pc_save =3D s->pc; } @@ -605,8 +609,10 @@ static TCGv eip_next_tl(DisasContext *s) TCGv ret =3D tcg_temp_new(); tcg_gen_addi_tl(ret, cpu_eip, s->pc - s->pc_save); return ret; + } else if (CODE64(s)) { + return tcg_constant_tl(s->pc); } else { - return tcg_constant_tl(s->pc - s->cs_base); + return tcg_constant_tl((uint32_t)(s->pc - s->cs_base)); } } =20 @@ -617,8 +623,10 @@ static TCGv eip_cur_tl(DisasContext *s) TCGv ret =3D tcg_temp_new(); tcg_gen_addi_tl(ret, cpu_eip, s->base.pc_next - s->pc_save); return ret; + } else if (CODE64(s)) { + return tcg_constant_tl(s->base.pc_next); } else { - return tcg_constant_tl(s->base.pc_next - s->cs_base); + return tcg_constant_tl((uint32_t)(s->base.pc_next - s->cs_base)); } } =20 @@ -2875,6 +2883,10 @@ static void gen_jmp_rel(DisasContext *s, MemOp ot, i= nt diff, int tb_num) } } new_eip &=3D mask; + new_pc =3D new_eip + s->cs_base; + if (!CODE64(s)) { + new_pc =3D (uint32_t)new_pc; + } =20 gen_update_cc_op(s); set_cc_op(s, CC_OP_DYNAMIC); @@ -2892,8 +2904,7 @@ static void gen_jmp_rel(DisasContext *s, MemOp ot, in= t diff, int tb_num) } } =20 - if (use_goto_tb && - translator_use_goto_tb(&s->base, new_eip + s->cs_base)) { + if (use_goto_tb && translator_use_goto_tb(&s->base, new_pc)) { /* jump to same page: we can use a direct jump */ tcg_gen_goto_tb(tb_num); if (!TARGET_TB_PCREL) { --=20 2.39.2