From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ADF9F7E for ; Wed, 2 Nov 2022 02:57:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BBB09C433C1; Wed, 2 Nov 2022 02:57:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1667357830; bh=u80g+fW4XlpYj3oS7L/JqPYcpuAhjIGvzeXfRrCxzD8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oI23VgXwXmZ7kHy/EVZc50UEi8KkZiVskOHEGWS/KCRQgR17LbN+gcQ8M3ktt4Swn 2qdK6IdZ2JxdPwPWokMvWj7w+0/9d6fluZzaF0ZKvIY7v2fIJp2b57uBtnj58AS38i TH+5EdQ+I/8o6ZDzTW0zZYUFPaUPVSS5WjbZs6oU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Qinglin Pan , Atish Patra , Palmer Dabbelt , Sasha Levin Subject: [PATCH 6.0 236/240] riscv: mm: add missing memcpy in kasan_init Date: Wed, 2 Nov 2022 03:33:31 +0100 Message-Id: <20221102022116.741944321@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221102022111.398283374@linuxfoundation.org> References: <20221102022111.398283374@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Qinglin Pan [ Upstream commit 9f2ac64d6ca60db99132e08628ac2899f956a0ec ] Hi Atish, It seems that the panic is due to the missing memcpy during kasan_init. Could you please check whether this patch is helpful? When doing kasan_populate, the new allocated base_pud/base_p4d should contain kasan_early_shadow_{pud, p4d}'s content. Add the missing memcpy to avoid page fault when read/write kasan shadow region. Tested on: - qemu with sv57 and CONFIG_KASAN on. - qemu with sv48 and CONFIG_KASAN on. Signed-off-by: Qinglin Pan Tested-by: Atish Patra Fixes: 8fbdccd2b173 ("riscv: mm: Support kasan for sv57") Link: https://lore.kernel.org/r/20221009083050.3814850-1-panqinglin2020@iscas.ac.cn Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin --- arch/riscv/mm/kasan_init.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c index a22e418dbd82..e1226709490f 100644 --- a/arch/riscv/mm/kasan_init.c +++ b/arch/riscv/mm/kasan_init.c @@ -113,6 +113,8 @@ static void __init kasan_populate_pud(pgd_t *pgd, base_pud = pt_ops.get_pud_virt(pfn_to_phys(_pgd_pfn(*pgd))); } else if (pgd_none(*pgd)) { base_pud = memblock_alloc(PTRS_PER_PUD * sizeof(pud_t), PAGE_SIZE); + memcpy(base_pud, (void *)kasan_early_shadow_pud, + sizeof(pud_t) * PTRS_PER_PUD); } else { base_pud = (pud_t *)pgd_page_vaddr(*pgd); if (base_pud == lm_alias(kasan_early_shadow_pud)) { @@ -173,8 +175,11 @@ static void __init kasan_populate_p4d(pgd_t *pgd, base_p4d = pt_ops.get_p4d_virt(pfn_to_phys(_pgd_pfn(*pgd))); } else { base_p4d = (p4d_t *)pgd_page_vaddr(*pgd); - if (base_p4d == lm_alias(kasan_early_shadow_p4d)) + if (base_p4d == lm_alias(kasan_early_shadow_p4d)) { base_p4d = memblock_alloc(PTRS_PER_PUD * sizeof(p4d_t), PAGE_SIZE); + memcpy(base_p4d, (void *)kasan_early_shadow_p4d, + sizeof(p4d_t) * PTRS_PER_P4D); + } } p4dp = base_p4d + p4d_index(vaddr); -- 2.35.1