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 9F7D320F079; Tue, 26 Aug 2025 13:07:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756213660; cv=none; b=CkU0KUpm99Q9M4YKn7IvyDU9ti1tHfb1hB9bC/5NW9IEbJgY0Cvuq57s8g6foUpqPzCPWZo1TjhSVYEeL9b1E2odkS5VOV1MpNkUfdPunApZvoivFei63Rc8gm9DcMYcf+DHnmaAA+rl1TK9QRsxEiIWATdNTBAYmNtfcXN8DNw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756213660; c=relaxed/simple; bh=NuQqvZOsP/+htdbC9G+z2to7U6lVypgBCrJo09WI2Ww=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sWVP8drvL2a+XCmu992QarYqIduyDqU3wdZSbIKy72D4ltfUGpCDKvUPSXurwGuFbs4d4QNnYony96JcINgjaIqbpTPMMWNVCMv1kQtR87UDCr+R4FEny8Cvxr+aW7+uXUp0YIvfoA2OI9WlIfjSnAZmjCwORHpJpmFDRTpQZwI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=MXn3X5za; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="MXn3X5za" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9BC07C4CEF4; Tue, 26 Aug 2025 13:07:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1756213660; bh=NuQqvZOsP/+htdbC9G+z2to7U6lVypgBCrJo09WI2Ww=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MXn3X5zaJ81z2KhiY6GqtkAfSL+SaUNrWmiLHt4udAkLuPbMlxp45J+0So2eZgfHG qkh9t+PASO/p3kFiNSEC0uNZOXumHrT1apSbVzyf8uOLKtyrlJunrg24GLlAqkPkXU 2uGg/gFmaQKQdXN4atov3XBK8LOEsOVeuN/8RcKM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Lorenzo Stoakes , Jann Horn , Julian Orth , "Liam R. Howlett" , Linus Torvalds , Shuah Khan , Vlastimil Babka , Andrew Morton , "Isaac J. Manjarres" Subject: [PATCH 6.6 431/587] selftests/memfd: add test for mapping write-sealed memfd read-only Date: Tue, 26 Aug 2025 13:09:40 +0200 Message-ID: <20250826111003.908737773@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250826110952.942403671@linuxfoundation.org> References: <20250826110952.942403671@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Isaac J. Manjarres" From: Lorenzo Stoakes [ Upstream commit ea0916e01d0b0f2cce1369ac1494239a79827270 ] Now we have reinstated the ability to map F_SEAL_WRITE mappings read-only, assert that we are able to do this in a test to ensure that we do not regress this again. Link: https://lkml.kernel.org/r/a6377ec470b14c0539b4600cf8fa24bf2e4858ae.1732804776.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Cc: Jann Horn Cc: Julian Orth Cc: Liam R. Howlett Cc: Linus Torvalds Cc: Shuah Khan Cc: Vlastimil Babka Signed-off-by: Andrew Morton Cc: stable@vger.kernel.org Signed-off-by: Isaac J. Manjarres Signed-off-by: Greg Kroah-Hartman --- tools/testing/selftests/memfd/memfd_test.c | 43 +++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) --- a/tools/testing/selftests/memfd/memfd_test.c +++ b/tools/testing/selftests/memfd/memfd_test.c @@ -285,6 +285,24 @@ static void *mfd_assert_mmap_shared(int return p; } +static void *mfd_assert_mmap_read_shared(int fd) +{ + void *p; + + p = mmap(NULL, + mfd_def_size, + PROT_READ, + MAP_SHARED, + fd, + 0); + if (p == MAP_FAILED) { + printf("mmap() failed: %m\n"); + abort(); + } + + return p; +} + static void *mfd_assert_mmap_private(int fd) { void *p; @@ -986,6 +1004,30 @@ static void test_seal_future_write(void) close(fd); } +static void test_seal_write_map_read_shared(void) +{ + int fd; + void *p; + + printf("%s SEAL-WRITE-MAP-READ\n", memfd_str); + + fd = mfd_assert_new("kern_memfd_seal_write_map_read", + mfd_def_size, + MFD_CLOEXEC | MFD_ALLOW_SEALING); + + mfd_assert_add_seals(fd, F_SEAL_WRITE); + mfd_assert_has_seals(fd, F_SEAL_WRITE); + + p = mfd_assert_mmap_read_shared(fd); + + mfd_assert_read(fd); + mfd_assert_read_shared(fd); + mfd_fail_write(fd); + + munmap(p, mfd_def_size); + close(fd); +} + /* * Test SEAL_SHRINK * Test whether SEAL_SHRINK actually prevents shrinking @@ -1603,6 +1645,7 @@ int main(int argc, char **argv) test_seal_write(); test_seal_future_write(); + test_seal_write_map_read_shared(); test_seal_shrink(); test_seal_grow(); test_seal_resize();