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([2602:ae:1541:f901:1d41:7730:d7dd:6f41]) by smtp.gmail.com with ESMTPSA id nl5-20020a17090b384500b00233ccd04a15sm11562013pjb.24.2023.04.04.08.52.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 Apr 2023 08:52:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1680623543; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=ZDfd7ct7wzbilubUOyiCb11C3SBKGvBqjiC3GyKJqDQ=; b=dWt3W6DngnlilRvCb2mSTe/G1dSM9sYrKAy4oRRQhiFU0qcO9ETq63DXVE38RrqAZd ZvKs2F66d3Ig/6JeVntGqlvY68cW5muWC+yMmvzwn6xXw6bKl7byAEa3zvEFYBSeOeq0 Ivc53INaiZN0/yjbCLSxyjYcQhf0Unk5vRpOEx5JuRHYKoCMRywGnDtTzvrYWBGzx7wG fV83I+kAVZ/O5tFcglz74eUVnmTCu5/q77B92kCgZ15FqSYk21K5iqgaQexL+9ES43kw rLINDoIz9UQA0pLVAf4sLpUV34hx7OtFcahZpTGg8hr+4xGLxoLjA2Q8wyX7nwfJJ8wp e1Ww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680623543; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=ZDfd7ct7wzbilubUOyiCb11C3SBKGvBqjiC3GyKJqDQ=; b=BzUGMkPi6H7RomZ7Tlr8zqezD/EysZEzgirrcf5REELBPmfeIVSKuMq0rgFlI+KRtp VGm9ifaADvv8KRR4TzE+QMFy6FF+0faPwRjyDu/MzXlY1Ean/z8rDUAujWX+kst+7CTw yl3IepLPpZYHUvRUtcz0TbOXNO/Svqs6x/bU2Rp+dCcCzqwdAIUy5Jvj+tXQ4NkVMxY8 lWICrriCElS4mWg/RX0rL5I8elIbtHwFsxi86NFD9NB8SnjBpJnBfGwMY7NMdvMNDpIJ pNuzbChA6JWZoLXW+hsui3yHBHcVxbZ6oY69/Yb9fZ2q/m2j2j5CSsLIxZOcr0Z+OpXG /qBw== X-Gm-Message-State: AAQBX9ewPl7iQdLFbbdy6+/6gntpXRDdkpiucDr1fUI9wlpXpxW+5Jz/ kKzMJPuVFj3gX/TfvmfLCnmdxhF/07K/d9V1aWc= X-Google-Smtp-Source: AKy350ZMRNI7eykQEgXMDtx1ot3ZTl7QoW9Lk+TjKhuZJfnQmZ+GvxY+v7jEaOwTund9tP51JdX7Cw== X-Received: by 2002:a17:90b:1647:b0:237:50b6:7835 with SMTP id il7-20020a17090b164700b0023750b67835mr3288422pjb.20.1680623542822; Tue, 04 Apr 2023 08:52:22 -0700 (PDT) From: Richard Henderson To: qemu-devel@nongnu.org Cc: peter.maydell@linaro.org, =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Subject: [PULL 1/4] Revert "linux-user/arm: Take more care allocating commpage" Date: Tue, 4 Apr 2023 08:52:17 -0700 Message-Id: <20230404155220.1572650-2-richard.henderson@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230404155220.1572650-1-richard.henderson@linaro.org> References: <20230404155220.1572650-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" 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=2607:f8b0:4864:20::62a; envelope-from=richard.henderson@linaro.org; helo=mail-pl1-x62a.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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-ZohoMail-DKIM: pass (identity @linaro.org) X-ZM-MESSAGEID: 1680623601279100003 This reverts commit 4f5c67f8df7f26e559509c68c45e652709edd23f. This exposes bugs in target_mmap et al with respect to overflow with the final page of the guest address space. To be fixed in the next development cycle. Reviewed-by: Philippe Mathieu-Daud=C3=A9 Signed-off-by: Richard Henderson --- linux-user/elfload.c | 37 ++++++++++--------------------------- 1 file changed, 10 insertions(+), 27 deletions(-) diff --git a/linux-user/elfload.c b/linux-user/elfload.c index b96b3e566b..f1370a7a8b 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -423,32 +423,12 @@ enum { =20 static bool init_guest_commpage(void) { - ARMCPU *cpu =3D ARM_CPU(thread_cpu); - abi_ptr want =3D HI_COMMPAGE & TARGET_PAGE_MASK; - abi_ptr addr; + abi_ptr commpage =3D HI_COMMPAGE & -qemu_host_page_size; + void *want =3D g2h_untagged(commpage); + void *addr =3D mmap(want, qemu_host_page_size, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); =20 - /* - * M-profile allocates maximum of 2GB address space, so can never - * allocate the commpage. Skip it. - */ - if (arm_feature(&cpu->env, ARM_FEATURE_M)) { - return true; - } - - /* - * If reserved_va does not cover the commpage, we get an assert - * in page_set_flags. Produce an intelligent error instead. - */ - if (reserved_va !=3D 0 && want + TARGET_PAGE_SIZE - 1 > reserved_va) { - error_report("Allocating guest commpage: -R 0x%" PRIx64 " too smal= l", - (uint64_t)reserved_va + 1); - exit(EXIT_FAILURE); - } - - addr =3D target_mmap(want, TARGET_PAGE_SIZE, PROT_READ | PROT_WRITE, - MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); - - if (addr =3D=3D -1) { + if (addr =3D=3D MAP_FAILED) { perror("Allocating guest commpage"); exit(EXIT_FAILURE); } @@ -457,12 +437,15 @@ static bool init_guest_commpage(void) } =20 /* Set kernel helper versions; rest of page is 0. */ - put_user_u32(5, 0xffff0ffcu); + __put_user(5, (uint32_t *)g2h_untagged(0xffff0ffcu)); =20 - if (target_mprotect(addr, qemu_host_page_size, PROT_READ | PROT_EXEC))= { + if (mprotect(addr, qemu_host_page_size, PROT_READ)) { perror("Protecting guest commpage"); exit(EXIT_FAILURE); } + + page_set_flags(commpage, commpage | ~qemu_host_page_mask, + PAGE_READ | PAGE_EXEC | PAGE_VALID); return true; } =20 --=20 2.34.1